Includes content previously published in Universe
THE
NIGHT SKY
MONTH BY MONTH Capella
Castor
GEMINI
Pollux
TAUR...
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Includes content previously published in Universe
THE
NIGHT SKY
MONTH BY MONTH Capella
Castor
GEMINI
Pollux
TAURUS
14 13
LEO
Arcturus
Pleiades
ARIES
Aldebaran
15
Hyades 12 Regulus
12 16
Procyon
Bellatrix
19
14
14
11
13
16
AQUARIUS 11
Mira 14
12
PISCES
Betelgeuse
11
VIRGO
OPHIUCHUS
CANCER
17
17 17
Rigel
14 15
Spica
13 19
TTARIUS
11 18
16 17
19
16 19
13 12
18
15
15
15
18
18 Antares
17
SCORPIUS Shaula
LIBRA
Fomalhaut
CAPRICORNUS
THE
NIGHT SKY
MONTH BY MONTH WILL GATER with GILES SPARROW
Content previously published in UNIVERSE
LONDON, NEW YORK, MELBOURNE, MUNICH, AND DELHI DK UK Editor Designer Managing Editor Managing Art Editor Production Editor Production Controller Publishing Manager Art Director Reference Publisher
Martha Evatt Duncan Turner Sarah Larter Michelle Baxter Sophie Argyris Phil Sergeant Liz Wheeler Phil Ormerod Jonathan Metcalf
Picture Researcher
Louise Thomas
Jacket Designer
Mark Cavanagh
DK INDIA Editors
Soma B Chowdhury Sudeshna Dasgupta Himanshi Sharma
Designers
Nidhi Mehra Pooja Pipil
Project Editor
Alka Ranjan
DTP Designers
Managing Editor Managing Art Editor DTP Manager
Vishal Bhatia Saurabh Challariya Pushpak Tyagi Rohan Sinha Ashita Murgai Sunil Sharma
First American edition, 2011 Published in the United States by DK Publishing 375 Hudson Street New York, New York 10014 A Penguin Company Looking at the Sun with the naked eye, binoculars, or a telescope can cause eye damage. The authors and publishers cannot accept any liability for readers who do not take precautions to observe safely. Modifying cameras or other equipment may invalidate the manufacturers’ warranty and readers do so at their own risk. Copyright © 2011 Dorling Kindersley Limited 11 12 13 14 15 10 9 8 7 6 5 4 3 2 1 179965—January 2011 Without limiting the rights under copyright reserved above, no part of this publication may be reproduced, stored in or introduced into a retrieval system, or transmitted in any form, or by any means (electronic, mechanical, photocopying, recording, or otherwise) the prior written permission of both the copyright owner and the above publisher of this book. Published in Great Britain by Dorling Kindersley Limited. A catalog record for this book is available from the Library of Congress. ISBN 978-0-7566-7148-8 Color reproduction by MDP, Bath Printed and bound in Singapore by Star Standard
Discover more at www.dk.com
CONTENTS LOOKING UP Looking into Space
8
Looking at Stars
10
The Changing Sky
12
Getting Started
14
MONTHLY SKY GUIDES Using the Sky Guides
18
January Overviews Highlights Northern Latitudes Southern Latitudes
20 22 24 26
February Overviews Highlights Northern Latitudes Southern Latitudes
28 30 32 34
March Overviews Highlights Northern Latitudes Southern Latitudes
36 38 40 42
April Overviews Highlights Northern Latitudes Southern Latitudes
44 46 48 50
May Overviews Highlights Northern Latitudes Southern Latitudes June Overviews Highlights Northern Latitudes Southern Latitudes
52 54 56 58
60 62 64 66
July Overviews Highlights Northern Latitudes Southern Latitudes
68 70 72 74
August Overviews Highlights Northern Latitudes Southern Latitudes
76 78 80 82
September Overviews Highlights Northern Latitudes Southern Latitudes
84 86 88 90
October Overviews Highlights Northern Latitudes Southern Latitudes
92 94 96 98
November Overviews Highlights Northern Latitudes Southern Latitudes
100 102 104 106
December Overviews Highlights Northern Latitudes Southern Latitudes
108 110 112 114
ALMANAC 2011–2012
116
2013–2014
118
2015–2016
120
2017–2018
122
2019
124
Glossary Index Acknowledgments
125 126 128
CONTRIBUTORS Will Gater is an astronomy journalist and author. He has written for several of the UK’s top astronomy and science magazines and promotes both these subjects with frequent appearances on television and radio. His blog and website can be found at www.willgater.com. Will is also the author of The Practical Astronomer, published by DK Publishing.
Giles Sparrow is a writer specializing in astronomy and space science. He has degrees in astronomy and science communication, and has worked for 15 years as an editor and author. An avid follower of the unfolding story of space exploration, he has written on space technology and the history of spaceflight in a wide range of books, including DK Publishing’s bestselling Universe.
LOOKING UP By watching the night skies and observing stars, planets, nebulae, and galaxies, stargazers can start to understand the vast Universe and all it encompasses. Astronomers picture the night sky as a starry sphere around Earth—“the celestial sphere”—which allows them to find their way around it and track the movements of night-sky objects as the Earth rotates.
Leonid meteor shower Shooting stars, here seen over Joshua Tree National Park in the USA, light up the sky. Eagerly anticipated every year, the Leonid meteor shower originates in the constellation Leo and annually peaks around November 17.
8
L OOK ING U P
LOOKING INTO SPACE The Earth is a part of a much greater Universe than our eyes alone reveal to us. Knowing our place within it helps us understand what we are seeing.
NGC 147
The Andromeda Galaxy lies 2.5 million light-years away from Earth, in the Milky Way
NGC 185
Andromeda I The stellar neighborhood lies in the Orion Arm of the Milky Way, around 26,000 light-years from its center
Andromeda II Andromeda III Triangulum Galaxy Galactic nucleus
THE SCALE OF THE UNIVERSE The Universe we live in is immense, extending far beyond the farthest edge of our Solar System. On a clear night, many stars are visible to the naked eye, and sometimes the faint glowing band of the Milky Way galaxy can be seen. From a very dark site, the Andromeda Galaxy, a staggering 2.5 million light-years away, is also visible. It is one of the most distant deep-sky objects that is visible to the naked eye. A telescope or a pair of binoculars allows us to see objects that are even farther away, such as other galaxies, nebulae, or star clusters in our galaxy, the Milky Way. However, there is much more to Alpha be seen, and amateur astronomers can see Centauri only a small fraction of it. Sun
Sirius
5,000 light-years THE MILKY WAY The Milky Way galaxy is a disk of gas, dust, and stars with a bulging nucleus. It can be seen as a faint band of light stretching across the sky on a clear night. The Sun is just one of the 200– 400 billion stars that the Milky Way contains.
Orbit of Neptune
Asteroid belt Sun Earth 5 light-years
THE STELLAR NEIGHBOURHOOD Earth
Beyond the edge of the Solar System, we leave the sphere of the Sun’s influence and move out into the stellar neighborhood. There are 106 stars within 20 light-years of the Sun, of which the closest is Proxima Centauri. A member of the Alpha (α) Centauri star system in the constellation Centaurus, Proxima Centauri sits 4.2 light-years away.
1 light-hour
THE SOLAR SYSTEM
The Moon moves around Earth in a slightly elliptical orbit
0.5 light-seconds THE EARTH AND MOON The Moon is the nearest celestial body to Earth, sitting 238,900 miles (384,400km) away. Light takes just over a second to reach Earth from the Moon.
The planets, moons, dwarf planets, comets, and asteroids that orbit the Sun are known as the Solar System. The most distant planet from the Sun is the gas giant Neptune, located an average of 2,794 million miles (4,497 million km) away from the Sun.
L OOK IN G IN T O S P A C E
THE LOCAL GROUP OF GALAXIES
THE LOCAL SUPERCLUSTER
The Milky Way is a part of a much larger gathering of around 40 galaxies that exist in the nearby Universe. These are known collectively as the Local Group. Some of the Local Group galaxies can be seen easily in the night sky, such as the Andromeda Galaxy, M31, and the Triangulum Galaxy, M33.
The Local Group is itself a part of a larger group, formed by thousands of galaxies. Known as the Virgo Supercluster, this swarm of galaxies is 100 million light-years wide. This supercluster nestles in vast interconnected filaments of other superclusters, which stretch across the Universe.
Ursa Minor dwarf galaxy The Milky Way
250,000 light-years Leo A 10 million light-years
MEASURING DISTANCE Because the Universe is such a large place, the units of distance we use in everyday life, such as miles or kilometers, are not very helpful in communicating the vast distances between stars and galaxies. Instead, astronomers use units called light-years to mark the vast distances between the stars and galaxies. One light-year is equal to the distance that a ray of light travels over the course of one year. The speed of light is an incredible 186,000 miles (300,000km) per second, so one light-year is a huge distance. As the distances (see below) between the galaxies and even nearby stars are so great,
light takes a long time to travel across space. When we see the light from an object like a star, it may have taken decades, centuries, or millions of years to reach us. Essentially, we are peering back in time because we see the object as it was when that light left it, not what it looks like “now.” So for an object like the Andromeda Galaxy, which is 2.5 million light-years away, we are seeing it as it was 2.5 million years ago. In contrast, the Sun’s light takes just 8.5 minutes to reach earth. In the chart below, the first division represents 6,200 miles (10,000km). Each further division marks a 10x increase in scale.
Peering into the depths The objects we see in the night sky are not all at the same distance from us. We can see everything from meteors shooting through our atmosphere to distant stars in our own galaxy.
DISTANCE FROM THE CENTER OF EARTH
Earth: radius 3,963 miles (6,378 km)
0
Moon:
Venus:
Sun:
238,900 26 million miles miles (384,400 km) (42 million km)
93 million miles (149.6 million km)
6,200 miles (10,000 km)
620,000 miles (106 km)
Saturn:
Kuiper Belt:
745 million miles (1.2 billion km)
approx 5.5 billion miles (9 billion km)
62 million miles (108 km)
1,000-light- Center of the Oort Nearest star year sphere: Milky Way: Cloud: (Proxima approx 1 Centauri): 90% of naked-eye 28,000 light-year
6.2 billion miles (1010 km)
4.2 light-years
6.2 x 1011 miles (1012 km)
stars are within 1,000 lightyears of Earth
62 trillion miles (1014 km)
light-years
6.2 x 1015 miles (1016 km)
Andromeda Galaxy:
Virgo Cluster:
Nearest quasar:
Edge of the visible Universe:
2.5 million light-years
52 million light-years
1 billion light-years
47 billion light-years 276 billion trillion miles (445 billion trillion km)
6.2 x 1017 miles (1018 km)
6.2 x 1019 miles (1020 km)
6.2 x 1021 miles (1022 km)
9
10
L OOK ING U P
LOOKING AT STARS When we look at the sky on a clear night we are greeted by countless stars. Stargazers use several methods to navigate their way around the magnificent night sky. THE CELESTIAL SPHERE The coordinate system of latitude and longitude helps us locate an object on the Earth’s surface. This system is based around a simple imaginary grid, where latitude—the horizontal lines on the grid—is measured north or south from the equator. Longitude, the vertical grid lines, is measured east or west from a point known as the prime meridian—a circle running through the North and South Poles and Greenwich in England. Similarly, astronomers project an imaginary sphere, also known as the celestial sphere, onto the sky. It has its own grid lines: the prime meridian, known as the “celestial
meridian,” and the equator, known as the “celestial equator.” Instead of latitude, astronomers use declination, which is measured in degrees and minutes, while longitude becomes right ascension, or RA, and is measured in hours and minutes. These coordinates help astronomers to locate celestial objects in space. Earth’s axis of spin
Earth’s axis is tilted at 23.5°
OUR VIEW OF THE CELESTIAL SPHERE Your view of the night sky depends on where you are on Earth’s surface. If you are located in the Southern Hemisphere, you see a different portion of the celestial sphere to someone who is observing the night sky in the Northern Hemisphere. However, from the equator you can view the entire celestial sphere over the course of a year. Limited view Your location on Earth determines the part of the celestial sphere that you can see.
Line perpendicular to ecliptic plane (plane of Earth’s orbit around the Sun) Celestial sphere
North Celestial Pole lies directly above Earth’s North Pole
Stars appear to be fixed on the sphere, which moves in the opposite direction to Earth’s spin
Earth’s spin
Autumnal equinox (first point of Libra) Earth’s North Pole
Earth’s equator The Sun and planets are not fixed on the celestial sphere, but move around on, or close to, the circular path known as the ecliptic
Earth
Celestial equator—a circle on the celestial sphere concentric with Earth’s equator
Defining positions To create a coordinate system where objects can be located on the night sky, astronomers imagine that Earth is embedded in an imaginary “celestial” sphere (as shown here).
Vernal or spring equinox (first point of Aries), one of the two points of intersection between celestial and ecliptic
Sun’s motion
South Celestial Pole lies below Earth’s South Pole
L OOK IN G A T S T A R S
MEASURING SIZES When observing the night sky for the first time it can be tricky to gauge how big a constellation or an object is by just looking at a star chart. However, there are some easy ways to measure apparent sizes on the sky. Held at arm’s length against the background of the sky, the hands and fingers can act as convenient measuring scales. For example, an index finger covers the Moon, which is only half a degree
Handspan A fully outstretched hand held at arm’s length spans about 22° of the sky.
Finger joints A side-on fingertip is about 3° wide; the second joint is 4°, the third joint 6°.
Finger width One finger at arm’s length will cover the Moon, which is less than 1° across.
STARHOPPING To navigate around the night sky using a star chart, you can use a method known as starhopping. This is a technique used by experts and beginners alike, and can come in handy when you are trying to find faint telescopic targets that may not be visible to the naked eye. The basic method is to first check a star chart (see pp.16-114) that shows the object you are trying to find, as well as any bright stars nearby. Then, start by finding a star or pattern of stars in the sky that you
across, while the width of an outstretched hand is roughly 22º across. Distances between objects on the night sky are measured in units called degrees. For example, the Andromeda Galaxy, or M31, appears roughly 3° across on the sky. A degree can be broken down into 60 arcminutes (with the symbol ‘), and each arcminute can be broken down into 60 arcseconds (with the symbol “). These units are sometimes written in slightly different ways and you might see them as minutes of arc, arcmin, seconds of arc, or arsec. These smaller units are often encountered when 1 degree dealing with the separation 90 degrees between double stars or the 360 degrees size of a nebula or cluster.
recognize and can easily locate. Once you find one recognizable star, you can then hop to another, possibly fainter star nearby, continuing to other stars until you eventually find your target. This is a great way to learn your way around the night sky, and is also handy when you use a pair of binoculars or a telescope. A more detailed printed chart from planetarium software will help you find objects when you are starhopping using a telescope, such as faint galaxies.
URSA MINOR
ANGULAR DISTANCES OBJECT OR DISTANCE
APPROXIMATE ANGULAR SIZE
Distance from the pointers in the Big Dipper to Polaris
28º
Distance between the Crux pointers
6º
Distance between pointers in the Big Dipper
5º
Your little finger at arm’s length
1º
The Moon (average size)
31’
The Sun (average size)
32’
Distance between Jupiter and Ganymede (the brightest of its main moons)
6’
Resolution of the naked eye (this means the ability of your eye to split two objects that are as close together as this)
3’ 25”
UNDERSTANDING CELESTIAL COORDINATES To understand right ascension and declination you need to know the reference points from which they are measured. The “zero” point for declination lies on a line on the celestial sphere called the celestial equator. You can think of it simply as Earth’s equator projected onto the imaginary celestial sphere. Objects above the celestial equator, toward the North Celestial Pole, have a positive declination, and those below, toward the South Celestial Pole have negative declination. For right ascension, the zero mark is a line called the “celestial meridian” marked at the moment where the Sun crosses the celestial equator.
Pherkad Polaris (The North Star)
Kochab
North Celestial Pole
Celestial meridian, the line of 0° right ascension Star position
START AT URSA MAJOR (THE BIG DIPPER) Alkaid
Mizar
1
Alioth 45°
Megrez
Phad
Dubhe
Merak
Celestial equator
Stellar signposts Arguably the most well-known “starhop” is the one that helps you find the “pole star” Polaris, which sits in Ursa Minor. Use the pointer stars of the Big Dipper asterism, Merak and Dubhe, in Ursa Major.
Declination angle 45° above celestial equator
Angle of right ascension (1 hour)
A star's position To find an object on the celestial sphere we need to know its RA and declination (see left). The star in the diagram above has a right ascension of 1 hour and a declination of +45°.
11
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L OOK ING U P
THE CHANGING SKY North celestial pole
The night sky changes over time, revealing a panorama of celestial objects. Understanding the sky’s movement helps us predict what will be visible and when.
w
DAILY SKY MOVEMENTS The stars seem to move across the sky as the night progresses. This is caused by Earth’s rotation on its axis. Once every 24 hours, Earth completes one rotation on its axis relative to the Sun. This is known as a mean solar day. Astronomers also measure the time taken for one rotation of Earth relative to the stars. This is known as a sidereal day, and is slightly
shorter than a solar day, at 23 hours 56 minutes and 4 seconds. This means a star will rise four minutes earlier each night. The difference between solar and sidereal days occurs because Earth has moved a little in its orbit around the Sun. The motion of the stars across the sky, over the course of an evening, depends on your location on Earth’s surface (see right).
S
N E Circumpolar area
w
S
N E
Moving constellation Because of a 4-minute difference between the length of a sidereal and a solar day, the constellations move westward a little from one night to the next. APRIL 1, 8PM
APRIL 8, 8PM
Earth at Northern Hemisphere’s winter solstice (December 21/22)
w
S
APRIL 15, 8PM
YEARLY SKY MOVEMENTS Not only do the stars move across the sky during the course of a single night, they also shift slowly around the sky over the course of a year. This means that at one time of the year, a constellation or a region of the sky may be visible when it is dark, say at midnight, while at another time it is hidden behind the Sun. This is because Earth moves around the Sun, so it appears as if the Sun moves against the background night sky.
Scorpius Ophiuchus
Libra
Sun
Virgo
Direction of the Sun’s movement
N E
Motion at mid-latitudes If you are observing from mid-latitudes, you will see the stars rise in the east and set in the west. Stars that never set are known as “circumpolar.”
Motion at the equator If you are standing at the equator, the stars will rise straight up from the east, pass overhead, and then move straight down to set in the west.
Point of the Northern Hemisphere’s autumnal equinox Earth’s rotation on its axis
Leo
Cancer Gemini Earth’s equator
Sun Aries
Earth at Northern Hemisphere’s summer solstice (June 21) Hemisphere visible from equator at midnight on the winter solstice
Taurus Celestial equator
Earth’s axis Capricornus
Ecliptic
Sagittarius Earth’s orbit
Motion at the north pole At the north pole, the stars circle in a counterclockwise motion around a point above you. At the south pole, they move in the opposite direction.
Hemisphere visible from equator at midnight on the summer solstice
June and December skies If you were on the equator at midnight in June you would see exactly the opposite half of the celestial sphere from the one you would see at midnight in December.
Aquarius
Point of the Northern Hemisphere’s vernal equinox
Pisces
Zodiac As the Sun appears to move against the background stars over the year it passes through several constellations. This band of constellations is known as the zodiac.
T H E C H A N G IN G S K Y
ECLIPSES As the Moon orbits Earth, it occasionally blocks the Sun’s light. The Moon’s shadow is cast onto Earth and anyone within the shadow will see a solar eclipse. Standing in the darker part of the Moon’s shadow, the umbra, you will see a total solar eclipse with the Sun completely covered by the Moon. If you are in the outer, lighter shadow, known as the penumbra, you will see a partial solar eclipse with only a portion of the Sun
Moon
Penumbra (outer, lighter shadow)
obscured by the Moon’s disk. If the Moon is too far away it cannot completely cover the Sun and an annular solar eclipse is seen from Earth. Similarly, if the Moon’s orbit takes it into the shadow cast into space by Earth, a lunar eclipse occurs. Eclipses require certain precise alignments of the Sun, Earth, and Moon, which is why an eclipse does not occur every time there is a full Moon or a new Moon.
Area of totality
Earth
Sunlight
Total lunar eclipse During a total lunar eclipse, the Moon can often be tinted a wonderful copper-red colou. This is the highlight of one of the greatest spectacles that can be seen in the night sky.
Penumbra (outer, lighter shadow)
Earth
A slight darkening of the moon occurs in the light outer shadow
Sunlight
Umbra (inner, darker shadow)
Solar eclipse Observers in the Moon’s umbral shadow see the Sun totally covered by the Moon. Those in the penumbra region only see a partial eclipse— where the Moon partly obscures the Sun’s disk.
PLANETARY MOTIONS Most of the planets can be seen in the night sky with nothing more than the naked eye. The planets Mercury and Venus are termed the “inferior planets” because they go around the Sun in orbits that are closer to the Sun than Earth’s orbit. Because of their proximity to the Sun, they are typically seen low in the sky before sunrise and after sunset. Mars and the planets beyond it are called
Umbra (inner, darker shadow)
Area of partial eclipse
“superior planets.” They can stray far from the Sun in the sky and can be seen late at night. As most of the planets orbit in roughly the same plane as they go around the Sun they can all be found relatively close to the line of the ecliptic (the path of the Sun on the sky). For more on their locations in the night sky, see the planet locator charts in the Monthly Sky Guides section of this book (pp.20–115).
The Moon is darkest within the umbra
Full Moon
Lunar eclipse During a lunar eclipse, the Moon enters the Earth’s lighter shadow, the penumbra. It then enters the darker region, or umbra, where it typically goes deep red. Finally, it moves out into the penumbra again.
Superior conjunction
Planet
Sun
Greatest western elongation
Greatest eastern elongation
Inferior conjunction
Angle of elongation Earth
INFERIOR ORBIT Conjunction
Sun Earth Opposition (closest to Earth)
Planet
SUPERIOR ORBIT Mercury and Venus Many of the planets can be seen very easily with the naked eye. In this photograph, the planets Mercury and Venus sit near each other in the sky after sunset—a striking sight.
Planetary positions These diagrams show several key positions in the orbits of the planets. Inferior planets are best seen near greatest elongation, while superior planets are generally best viewed around opposition.
13
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L OOK ING U P
GETTING STARTED Many of the night sky’s finest sights can be seen with the naked eye, but telescopes and binoculars allow us to see farther and explore celestial objects in more detail. PLANNING AHEAD Preparation is the key to an enjoyable night’s astronomy under the stars. Start by thinking what you want to look at and the equipment you will need to see it. For example, if you are
using equipment that requires batteries, make sure they are charged and ready. Additionally, take a good star chart with you (see pp.16–114), so that you know the location of the objects you want to observe. Also, think about what to wear when observing. The clearest nights can often be the coldest, so it is crucial to wear warm clothes such as a windproof jacket as well as waterproof trousers, a warm hat, and stout shoes. If you are traveling out to a remote location, make sure to tell someone where you are going. Remembering these basic things will ensure your observing goes smoothly. Viewing location The location from which you observe is as important as the equipment you use. Ideally, head toward a dark sky site, away from sources of light pollution, such as streetlamps and houses.
BINOCULARS Loved by beginners and experts alike, binoculars are a simple, generally inexpensive way to explore the night sky. A good pair of binoculars is capable of showing a huge variety of objects on any given night. With even a small pair the rich star fields of the Milky Way, glittering open star clusters, and the Moon’s rugged surface are all wonderful sights. Binoculars come in many different Focus wheel
CHECKLIST t8BSNDMPUIFT t(MPWFT t3FEMJHIUGMBTIMJHIU t/PUFQBEBOEQFO t"OZFRVJQNFOU UFMFTDPQFT CJOPDVMBST FUD t$PNQBTT t4UBSDIBSU t8BSNESJOL t#MBOLFUPSGPMEBCMFDIBJS Red light torch To preserve your night vision, a red light torch is crucial. This can be bought or easily made by covering a regular flashlight with a red candy wrapper, secured by an elastic band.
sizes and are defined by two numbers that can often be found marked on their sides. The first number is the number of times the binoculars can magnify a view, and the second number is the size of the main (or objective) lens in millimeters. For example, binoculars that magnify 10x with 50mm diameter lenses are said to be a “ten by fifty” pair of binoculars.
Eyepiece Eyepiece Light path Prism
Prism
Light path Objective lens
Objective lens
Compact binoculars These “roof-prism” binoculars use a design where light passes through a group of close prisms, making them more compact.
Standard binoculars “Porro-prism” binoculars with a folded light path are popular with astronomers because their typically larger lenses result in brighter images.
Large binoculars Large binoculars can provide stunning views of celestial objects; however, they require tripods because they can be hard to hold steady.
G E T T IN G S T A R T E D
TELESCOPES Designed to collect light from celestial objects, telescopes also magnify the view and allow us to see objects in more detail. A telescope’s crucial specification is its aperture—the size of its main mirror or lens—which is usually measured in millimeters or inches. The larger the main mirror or lens, the more light it will be able to gather. A typical small telescope has an aperture of 4–6 in (10–15 cm). Telescopes can be
held on different types of mounts. These must be sturdy enough to provide a firm, stable platform for the optics and allow the telecope to aim accurately. Equatorial mounts are capable of aligning to the rotation axis of the night sky for simplified tracking. More compact in comparison to equatorial mounts, altitude-azimuth mounts work by moving around 360° (in azimuth) and up and down (in altitude). Finderscope Eyepiece
Eyepiece
Telescope tube assembly
Equatorial mount
Altitude-azimuth mount
Telescope tube assembly
15
RECORDING WHAT YOU SEE There are many ways to record the things you observe when studying the night sky. The simplest is to make a sketch of what you see with the naked eye or through the eyepiece of a telescope or binoculars. Make sure to use a good quality pencil and an artist’s sketch pad. To sketch clusters, nebulae, and other deep-sky objects, the best way to begin is to draw the brighter stars first. Another popular method, although a little more tricky to master, is astrophotography. This involves connecting a camera to your telescope to take pictures. However you record your observations, be sure to note down the observing conditions, the time and date, your name and location, details of the equipment used, and the name of the object observed.
Slow motion control Main mirror located inside tube
Tripod
Newtonian reflector This simple design, consisting of a tube on a mount and tripod, is ideal for a beginner. The eyepiece is located at the top of the tube and extends from the side.
Dobsonian The Dobsonian reflector uses a simple altitude-azimuth mount. Tending to have larger apertures for their price, Dobsonians are excellent deep-sky telescopes.
OBSERVING WITH THE NAKED EYE Focus adjustment knob Eyepiece Telescope tube assembly
Altitude-azimuth mount
There is a wealth of things to see in the night sky using nothing more than the naked eye. For example, meteor showers are best seen by sitting back on a chair and just watching the sky. Similarly, no equipment is needed to marvel at the great expanse of the Milky Way galaxy, or the many stars within it, from a dark sky site. To get the most spectacular naked-eye views of the night sky you must head away from light-polluted towns and cities.
An astro image of the North America Nebula Astrophotographers create stunning images of the night sky, with the help of sensitive cameras mounted on telescopes. They stack together many individual exposures to create a final detailed image.
Focus and zoom adjustment
Camera body
Tripod with eyepiece holder
Camera lens
Mount adjustment handle
Tripod head
Adjustment handle
Refractor Refractor telescopes have a classic telescope design, their lenses collect light and produce an image in the eyepiece. They are good for observing a range of celestial objects.
What you can see Many celestial objects are visible to the naked eye, including the Milky Way, the Andromeda Galaxy, meteors, noctilucent clouds, and the aurorae (shown above).
Digital SLR These cameras are used by astroimagers because they can be attached to telescopes and their shutters can be left open to gather the faint light from celestial objects.
MONTHLY SKY GUIDES During the course of a year, our view of the night sky changes from month to month as Earth orbits the Sun. Some constellations are always in the sky, while others appear and disappear over different regions. The following monthly sky guides help you recognize patterns and track changes in the Northern and Southern Hemispheres.
The aurorae The Northern and Southern lights, or the aurorae, occur in high latitudes of both hemispheres, such as Wapusk National Park in Canada, as seen here. They cause spectacular displays that often last for hours and end with a ribbonlike rippling effect.
MO NT H LY S KY GUID ES
USING THE SKY GUIDES This month-by-month guide features charts that show the whole night sky as it appears from different locations. These pages explain how to get the most from the information in the charts. MONTHLY OVERVIEWS For each month of the year, a double-page spread outlines the different celestial phenomena in the sky. These include bright stars, constellations, deep-sky objects, and meteor showers. The constellation box on these pages discusses a key constellation in detail, pointing out its bright stars. 20
These pages also feature planet-locator charts, which show the band of sky that lies on either side of the ecliptic, where the planets appear. These charts should be used in conjunction with the information supplied in the following highlights pages, whole-sky charts, and the Almanac.
M O NTH LY S K Y G U IDE S : OV E R V IE WS
J AN U ARY
19
18
17
16
15
14
13
12
Uranus and Neptune The magnified insets of the main chart show Uranus and Neptune, the two outermost planets, as they move relatively slowly through our sky.
11
AQUARIUS
21
9 PM
MIDNIGHT
Each month has its own overview pages
SOUTHERN LATITUDES
JANUARY In January skies, all eyes are firmly fixed on the striking constellation Orion, the Hunter. The Milky Way is another spectacular sight to behold this month. If you are in the Southern Hemisphere, look high in the sky for the Large Magellanic Cloud.
The text highlights the most prominent stars, deep-sky objects, and meteor showers
SIGHTS OF INTEREST If you are exploring the constellation Orion, you will see the Orion Nebula, M42, a bright deep-sky object lying
south of the chain of three stars that makes up Orion’s belt. This nebula is easily visible through binoculars from northern latitudes and can be seen with the naked eye as a hazy patch. The open star clusters M36, M37, and M38 in Auriga are also worth a look with binoculars. METEOR SHOWERS The Quadrantid meteor shower kicks off around January 3–4 every year. These meteors seem to originate from a point near the handle of the Big Dipper in the constellation Ursa Major. This area was once occupied by the now-obsolete constellation Quadrans, after which the meteor shower is
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
21
Alpha (α) Aurigae, or Capella, 0.1
Aurigae
Aur
December–February
The constellation Auriga, the Charioteer, can easily be spotted within the band of the Milky Way between the constellations 50º Perseus and Gemini. Its brightest star is the magnitude 0.1 Capella. There are several interesting open 0º clusters in Auriga that make ideal targets for astor binoculars or a small telescope. Pollux
NORTHERN LATITUDES THE STARS When viewing in January, you will immediately notice the brightest star in the sky, Sirius, in the constellation Canis Major. Visible from mid-northern latitudes, Sirius twinkles above the southern horizon. Directly above you is the yellowish star Capella in Auriga. Meanwhile, in the northeast lies a familiar asterism, the Big Dipper. In the northwest, look for the faint band of the Milky Way passing through into Perseus and Cassiopeia.
Size ranking
7h
6h
LYNX
δ
ξ PERSEUS 9
ψ
1
AURIGA
β
2 ψ7 ψ
Capella
π
λ
NGC 2281
63 UU
θ
ν τ υ
χ κ
ε
η
16
NGC 1664
SIGHTS OF INTEREST It is not just observers in the northern latitudes who enjoy a good view of the constellation Orion. The Orion Nebula is ideally placed high in the sky, even if you are observing from southern latitudes. The Large Magellanic Cloud in the constellation Dorado can be seen with binoculars on January evenings. Among its
ζ
μ
4
M38 NGC 1907 AE IC 405
M36
GEMINI RT
α
2
ι
M37
Brightest star
Genitive
43
Alpha (α) Canis Majoris, Canis Majoris or Sirius, -1.4
CMa
January–February
—50°
6h
7h
The Milky Way This view of the Milky Way shows the regions toward the constellations Crux, the Southern Cross, and Carina, the Keel.
—40°
MONOCEROS
–10º
CANIS MAJOR NGC 2360
γ
–20º
ι π
θ μ α
ORION
Castor
Sirius
ν3
β
2
LEPUS
15 M41
UW NGC
τ
2362
ω
27
η
–30º
ο2
ο1
δ σ ε
ξ
2
ξ
GEMINI
Pollux
Adhara
λ
κ
ζ
TAURUS
3 AM
PISCES
19 18
Aldebaran
NEPTUNE
Capella
16
19
15
18
13
17
Hyades 16
12
15
14
11
Castor
13
12
11
Betelgeuse
3 PM
CETUS
GEMINI
—20°
17
AQUARIUS
Procyon
Pleiades
TAURUS
14
Bellatrix
ARIES
13
LEO
—10°
Aldebaran
15
Hyades
10°
Regulus
12
PISCES
12
CANCER
10°
Betelgeuse Procyon
16
Bellatrix
19
AQUARIUS
0° Mira
17
12
14
14
11
13
13 19
11 18
17
SAGITTARIUS
19
16 19 Antares
–10°
14 15
13 15
12
15
S K Y
18
–20°
11
E V E N I N G
POSITIONS OF THE PLANETS
18 17 –30°
LIBRA
This chart shows the positions of the planets in January from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
SCORPIUS Shaula
–40°
S
–50°
M
Planet-locator charts (right) These charts show the position of the planets at 10pm local standard time on the 15th day of the month. Each planet is represented by a colored dot, and the number inside each dot refers to a particular year. Each chart shows the planets’ positions in relation to the 13 constellations along the ecliptic.
O
R
N
I N
K
Y
G
Mercury
Mars
Saturn
Venus
Jupiter
CAPRICORNUS
Fomalhaut
except Mercury, the dot indicates the planet’s position on January 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Ecliptic
–30°
Mars’s position on January 15, 2011
11
Uranus
–50°
Key to planet-locator chart
Saturn’s position on January 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
Capella
Castor
GEMINI
Pollux
Pleiades
TAURUS
14
ARIES
13
LEO
Arcturus
Aldebaran
15
Hyades
Ecliptic
12
CANCER
Regulus
12
PISCES
Bellatrix
19
AQUARIUS 11
Mira
17
14 12 14
13
17
14 15
13 15
12
18
15
15 11
18
ntares
LIBRA
CAPRICORNUS
Fomalhaut
The planet-locator chart shows a portion of the celestial sphere on either side of the ecliptic
Celestial sphere
MONTHLY HIGHLIGHTS The monthly highlights pages detail a selection of the best objects to look for in the night sky, such as galaxies, clusters, and double stars. Each month has four charts, which show the skies looking north and south from both northern and southern latitudes (see p.19). The colored lines indicate the region of the sky that is visible from the given latitude. The text discusses objects that are well placed for observation in the region of sky shown on the chart. There are also tips on how to locate the objects, some of which are illustrated with photographs. To hone in on objects in the sky, you can cross-reference these charts with the detailed sky charts on the following pages.
17
Rigel
Spica
16
Celestial equator Position of a planet shown by colored dot
Betelgeuse Procyon
16 11
VIRGO
19
22
MO N TH L Y SKY G U ID ES: H IG H L IG H TS
JANUARY NORTHERN LATITUDES
Date
JANUARY SOUTHERN LATITUDES
STAR MAGNITUDES
OBSERVATION TIMES
LOOKING NORTH
Standard time
Daylight-saving time
December 15
Midnight
1 am
January 1
11 pm
Midnight
January 15
10 pm
11 pm
February 1
9 pm
10 pm
February 15
8 pm
9 pm
-1
0
1
2
3 and above
LOOKING NORTH
Zenith
40°S
AURIGA GEMINI
40ºN
ERIDANUS
Ecl ipt ic
Castor
Rigel
60ºN
Sirius
Betelgeuse
TAURUS
CETUS
URSA MINOR
Capella
Castor
Ecl i pt
Ho riz o
n 20
LEO
0ºN on 6 Horiz
Horizon 20ºS
EA
ST
W
ES
T
URSA MAJOR
CASSIOPEIA
ANDROMEDA
EA
ST
The Hyades The “V” of the Hyades star cluster is an unmistakable sight; its members form the head of Taurus, the Bull. The bright orange-red star nearby, Aldebaran, is not actually a part of the cluster.
Big Dipper
Horiz on 0º
LOOKING SOUTH
LOOKING SOUTH Zenith
Zenith
60°N
0°
The constellations Vela, Carina, and the long and winding Eridanus are all on show at this time of the year. The planetary nebula NGC 3132 in Vela is an interesting object when seen through a telescope. While you are observing the eastern part of the sky, be sure to look for the globular cluster NGC 3201. The open star cluster NGC 2547, also in Vela, is a good target for binoculars. Use a small telescope to bring into focus the scattered open cluster M47 in the constellation Puppis, the Stern.
ORION
Capella Rigel Sirius
40ºN
GEMINI
Propus 20ºN
CANIS MAJOR
TAURUS
40ºS
ORION Aldebaran CANCER
ic
ERIDANUS
PUPPIS
Canopus
ARIES
LEO
pt
20ºS
MONOCEROS
PERSEUS
Castor Pollux
Regor
Betelgeuse Procyon
PICTOR PISCES
MONOCEROS
Sirius
Rigel
CETUS VELA
Regulus PUPPIS
on Horiz
M35 in Gemini The open cluster M35 sits near the star Propus in Gemini. While a small telescope will show the cluster clearly, a larger telescope will also show the fainter cluster NGC 2158 sitting nearby.
Horiz on 20 ºN
CETUS
HYDRA CENTAURUS TUCANA
Canopus
ST
CARINA
PHOENIX
ERIDANUS
CANIS MAJOR
60 ºN
Horizon 40ºN
EA
Achernar
Mira
HYDRA
VELA
CARINA
PICTOR
Text highlights the most prominent celestial objects
Regulus
PERSEUS
ºN
Horizon 40ºN
Vega
AURIGA
Northern and southern latitudes are covered separately
ic
Horizon 4 0ºS
HERCULES
The constellation Orion, the Hunter, is a magnificent sight to behold with the naked eye. Particularly striking is the color difference between Orion’s two brightest stars, the orange-red Alpha (α) Orionis, Betelgeuse, and the blue-white Beta (β) Orionis, Rigel. A telescope or a pair of binoculars will reveal the stunning Orion Nebula, M42, which sits in Orion’s sword. The variable star Mira in Cetus and the open cluster M35 in Gemini are also well placed for observation.
23
PISCES
BOÖTES
CYGNUS
Pollux
AURIGA
ARIES
Mizar
DRACO Deneb
GEMINI LEO
Alcor
HYDRA
CANCER Regulus
Big Dipper
CEPHEUS
T
Procyon
Aldebaran
URSA MAJOR
Polaris ANDROMEDA
PEGASUS
ES
PUPPIS MONOCEROS
0º
ORION CANCER
CASSIOPEIA
CANIS MAJOR
20ºS
Pollux Capella
PERSEUS ARIES
W
The bright star Castor, Alpha (α) Geminorum, in Gemini, is an interesting target if observed through a telescope. Appearing as a single star to the naked eye, Castor is actually a multiple star system composed of six stars, three of which can be observed with a small telescope. Also on show are the open clusters M36, M37, and M38 in Auriga, the Charioteer. In the west, the prominent “V” shape of the Hyades star cluster in Taurus is a fine sight to the naked eye or through binoculars.
Zenith
20°N
TAURUS
PISCES
The Double Cluster Both NGC 884 and NGC 869 can be seen through binoculars or a small telescope as two fuzzy patches made of many stars, sparkling against the rich star fields of the Milky Way galaxy.
The inner planets (above) The main body of the planet-locator chart shows the six planets closest to the Sun. The bands along the top and bottom of the chart indicate in local time when that area of sky is highest in the sky. However, the local sunset and sunrise times will affect the darkness of the sky and the visibility of the planets.
JAN U AR Y
The pair of star clusters NGC 884 and NGC 869 are known together as the Double Cluster. They lie in Perseus, in the northwest in January skies, and are a truly wonderful sight through binoculars or a small telescope. The constellation Ursa Minor, the Little Bear, is well placed for observation in January. In the east, the double star of Alcor and Mizar in Ursa Major, the Great Bear, can be spotted through a small telescope. Capella, in the constellation Auriga, is almost overhead.
The time when an area of the sky is visible: evening sky (from sunset to midnight) or morning sky (from midnight to sunrise)
Neptune
Earth’s axis of rotation
Celestial equator
S K Y — -10°
Celestial equator
–40°
EXAMPLES
11
— 0°
17
Rigel
E V E N I N G
Rigel
17
Spica
16
18
15 16
0°
11
11 14
–10°
—30°
13
URANUS 6 PM
14
VIRGO
Declination coordinates
P
14
COLUMBA
9 AM
OPHIUCHUS
The time of night (local time) when this area of sky lies on the meridian (an imaginary line that runs north to south)
1
PUPPIS
Pollux
18
Highest in sky at 10 pm
MIDNIGHT
Arcturus
–20°
Abbreviation
9 PM
MIDNIGHT
6 AM
NOON
Size ranking
Sitting at the heels of Orion, Canis Major, the Greater Dog, is home to the brightest star of the entire night sky—Sirius, Alpha (α) Canis Majoris. Sirius is a brilliant white star with a magnitude of -1.4. Canis Major represents one of the two hunting dogs of Orion, the Hunter, which sits nearby. It is home to two fine open clusters, NGC 2362 and M41.
β Tau
the trails of meteors appear to come, is quite low in the northeastern sky, even at midnight.
Capella
CANIS MAJOR
Alnath
TAURUS
named. At the peak of the shower, you may be able to spot as many as 100 meteors an hour, but they appear relatively faint. The meteor shower is best observed from rural or light pollution-free areas. The peak lasts only a few hours and their radiant, the point in the sky from which
and its star fields and clusters can be seen with binoculars or a small telescope. If you are located around latitude 20°S the star cluster M41, near Sirius, will be directly above you. Under good conditions M41 can be seen with the naked eye.
sparkling stars, you will find the Tarantula Nebula, which appears to the naked eye as a glowing patch the size of the full Moon. Do not forget the Small Magellanic Cloud in Tucana either—it lies to the southwestern horizon this month,
Auriga is low in the north on clear January evenings and the rich Milky Way star fields of Carina and Centaurus, which are home to many interesting celestial sights, are sitting low in the southeast.
THE STARS If you are observing the skies from southern latitudes this month, you will find the bright star Canopus in the constellation Carina sitting high in the sky, while Sirius is almost overhead. Orion’s brightest stars, Rigel and Betelgeuse, are also high up. Aldebaran, the brightest star in the constellation Taurus, shines with a red-orange tint lower in the north. The star Capella in the constellation
A U RI G A
Ec li
18
PHOENIX
W
ES
T
0º izon Hor Horizon 20ºS Hor izon 40º EA S S
T
CRUX
OCTANS
AQUARIUS
β Centauri
GRUS
α Centauri
PAVO ARA
Fomalhaut
WE
ST
NGC 2547 The gorgeous magnitude 4.7 star cluster NGC 2547 sits very close to the star Regor, Gamma (γ) Velorum, in the constellation Vela. It is a fine sight through binoculars or a small telescope.
Photographs show some of the most interesting features to observe Sky charts show positions of the stars looking north and south
USING THE SKY GUIDES
THE WHOLE-SKY CHARTS In addition to the monthly highlights and overviews pages, there are two whole-sky charts for every month. These charts show the position of the stars at 10pm local time on the 15th day of the month, for both the Northern and Southern Hemispheres. They project the half of the celestial sphere that would be visible to you without any obstruction on the horizon. To use the whole-sky charts, first use the world map (bottom right) to find the colored latitude line that is closest to your observing location. Then turn to the chart for the month you are observing in. Next, look for the horizon line that is colored the same as the latitude line that is closest to your location. The sky plotted within the horizon’s boundaries is visible from your location during that month for the times shown. Now turn to the appropriate month and position yourself and the chart (see right).
South NORTHERN LATITUDES
South SOUTHERN LATITUDES
Orientation To view the northern sky, turn northward and hold the map flat with the label NORTH closest to you. The colored northern horizon line on the chart corresponds to the horizon in front of you. To view the south, turn yourself and the map around.
Star-motion diagrams These diagrams show the direction in which the stars appear to move in the sky as the night progresses. Stars near the celestial equator appear to move from east to west, while circumpolar stars circle around the celestial poles without setting.
Constellation name
-1
0
1
2
3
4
Variable star
5
N LY
M I LE O NO R
Globular cluster
Galaxy
Open cluster
Diffuse nebula
Planetary nebula
Horizons 60°N 40°N 20°N
DEEP -SKY OBJECTS
60°N
Zeniths
40°N
20°N
JANUARY NO RT HERN L AT IT U DES
25
Asterism name STAR MAGNITUDES
Ecliptic
POINTS OF REFERENCE
X
SA R UR J O A M
LOO K I N G
South
SO UT H
SOUTH SUNRISE AND SUNSET ON 15TH JANUARY
LMC
M81 RET I
er
ipp
DO RA DO
U CUL
North
M
STAR MOTION
Canopus
U
ST LA
LO G
CAELUM
IUM
C O LU M B A
PI S
U
O PH
EN
TH
IX
Adhara
L E PU S
IA TL
M41
C AN MA I S JO R
AN
M93
M4
46
E RI
DA N
RN
AX
US
Sirius
7
Rigel M42
48
CE
M
DR HY
C
Bellatr
ix
geuse
Betel
cy
S EX
67
ran
es
lus
I
M35
IN
M44
Regu
Hyad
M
M
M37
M36
45
US
(P
leia
I GA
de
PE R S
s)
EU S
Ca
stor
Pollu
AU R
M38
x
L EO
Aldeba
CER CA N
N TA
S
Pro
M
UR TA
OR I O N M1
GE
ic
Eclipt
TU
ER OS
on
EAST
A
NO C
O M
IS AN
M
I
R
A RI E S
LE O
R PE
SE
A ED
M52
M87
I
Dip
U RS A MIN OR ar
M51
Miz
39
M101
Den
eb
US
O
D RACO
ST
N
M29
R
T
H
ES ÖT BO
EA
CY GN
W
ES
T LYR A
M ONT HL Y S KY GU I D E S: SK Y GUI DE S
O
R
TH
M13
M57
OBSERVATION TIMES Date
Standard time
Daylight-saving time
December 15
Midnight
1 am
January 1
11 pm
Midnight
January 15
10 pm
11 pm
February 1
9 pm
10 pm
February 15
8 pm
9 pm
NORTH
LO OK I N G
N O RTH
Daylight-saving time
December 15
Midnight
1 am
January 1
11 pm
Midnight
January 15
10 pm
11 pm
February 1
9 pm
10 pm
February 15
8 pm
9 pm
Observation times Each chart shows the sky as it appears at 10pm local standard time mid month. However, this view can also be seen at other times of the month, as well as one hour later when local daylight saving time is in use. These times range from midnight in the middle of the previous month to 8pm in the middle of the next month.
JANUARY | NORTHERN LATITUDES DEEP-SKY OBJECTS
STAR MAGNITUDES -1
0
1
2
3
4
5
Variable star
Galaxy
POINTS OF REFERENCE
Globular cluster
Open cluster
Diffuse nebula
Planetary nebula
Horizons 60°N 40°N 20°N
Zeniths
60°N
40°N
20°N
Ecliptic
60°N
24
Variable star
N
NA RO IS C O R E AL BO
M92
Vega
HERC UL ES
5
Standard time
3
HE U S
Date
M
C EP M
Big
Polaris
RT A
M64
31
S NE I C CA N AT VE
M53
M
M
M81
r
LA CE
S
B E CO M RE A NI CE S
M
SA R U R A JO M
9
C AM E LOP A RDA LIS
3
EAST
M34
LU N GU
O DR
C 86
4
M10
Main features Besides showing the band of the Milky Way galaxy, the whole-sky charts also highlight many stars, constellations, deep-sky objects, asterisms, and the path of the Sun—also known as the ecliptic.
MI LEO NO R
M33
T RI A
AN
C 88
E IA
Deep-sky object name or number
M50
NO
Mir a
PI S C E S
NG
IO P
pe
HEU
DEEP-SKY OBJECTS Globular cluster
C ES
C EP
Star magnitude This panel shows the approximate magnitudes of the stars plotted on the whole-sky chart. In astronomy, the brighter a star the lower its “magnitude” value; bright objects may even have a negative value.
Galaxy
NX LY
S
4
PI S
AS U
3
A U RI G A
NG
SS
1
OBSERVATION TIMES lla
CA
M5
M101
Cape
US
P EG
2
S
2 WEST
1
WEST
0
T OR
M5
STAR MAGNITUDES -1
SCU LP
Horizons and zeniths The stars shown near the center of each chart are close to the point directly overhead, known as the zenith, while stars near the chart’s edge appear close to the horizon. Color-coded lines and crosses are used to identify the horizon and zenith for each of the three latitude projections on each monthly whole-sky chart.
ar
Miz
M
FO
Celestial sphere Each whole-sky chart shows an area greater than half a celestial sphere because it combines three different projections of the night sky, as seen from three different latitudes. Each month the sky charts show the sky as it appears from 60°–20°N on the northern latitudes chart and from 0°–40°S on the southern latitudes chart.
PY X IS
Viewer
Star name
PU P
SO
T
SO
VE
RO HO
ES
C V
gD
Bi
TH
EA
PI C T O R
W
Horizon
CAR INA
Zenith
North
JANUARY | NORTHERN LATITUDES
Horizon
Zenith
North
40°N 20°N 0° 20°S 40°S POINTS OF REFERENCE
Open cluster
Diffuse nebula
Planetary nebula
Deep-sky objects This panel displays the symbols for deep-sky objects, including galaxies, clusters, and nebulae shown on the whole-sky charts.
Horizons 60°N 40°N 20°N
Zeniths
60°N
40°N
20°N
Ecliptic
Points of reference To help you remember which horizon line or zenith marker applies to your location, this bar shows the different colors that correspond to the different latitudes.
Lines of latitude Use this map to find the colored latitude line that is closest to your location. This is the color of the line you need to find on the sky charts (see above). Note that a 10° difference in latitude has little effect on the stars that can be seen.
19
20
MO NT H LY S KY GUID ES: OVERVIEW S
JANUARY In January skies, all eyes are firmly fixed on the striking constellation Orion, the Hunter. The Milky Way is another spectacular sight to behold this month. If you are in the Southern Hemisphere, look high in the sky for the Large Magellanic Cloud.
A U RI G A
SIGHTS OF INTEREST If you are exploring the constellation Orion, you will see the Orion Nebula, M42, a bright deep-sky object lying
south of the chain of three stars that makes up Orion’s belt. This nebula is easily visible through binoculars from northern latitudes and can be seen with the naked eye as a hazy patch. The open star clusters M36, M37, and M38 in Auriga are also worth a look with binoculars. METEOR SHOWERS The Quadrantid meteor shower kicks off around January 3–4 every year. These meteors seem to originate from a point near the handle of the Big Dipper in the constellation Ursa Major. This area was once occupied by the now-obsolete constellation Quadrans, after which the meteor shower is
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
21
Alpha (α) Aurigae, or Capella, 0.1
Aurigae
Aur
December–February
The constellation Auriga, the Charioteer, can easily be spotted within the band of the Milky Way between the constellations 50º Perseus and Gemini. Its brightest star is the magnitude 0.1 Capella. There are several interesting open 0º clusters in Auriga that make ideal targets for astor binoculars or a small telescope. Pollux
NORTHERN LATITUDES THE STARS When viewing in January, you will immediately notice the brightest star in the sky, Sirius, in the constellation Canis Major. Visible from mid-northern latitudes, Sirius twinkles above the southern horizon. Directly above you is the yellowish star Capella in Auriga. Meanwhile, in the northeast lies a familiar asterism, the Big Dipper. In the northwest, look for the faint band of the Milky Way passing through into Perseus and Cassiopeia.
Size ranking
7h
6h
LYNX
δ
ξ PERSEUS 9
ψ1
ψ7 ψ
AURIGA
β
2
Capella
π
α λ
NGC 2281
63 UU
θ
ν τ υ
χ
16
NGC 1664
ζ 4
M38 NGC 1907 AE IC 405
M36
κ
η
μ
GEMINI RT
ε
2
ι
M37
Alnath
βTau TAURUS
named. At the peak of the shower, you may be able to spot as many as 100 meteors an hour, but they appear relatively faint. The meteor shower is best observed from rural or light pollution-free areas. The peak lasts only a few hours and their radiant, the point in the sky from which
the trails of meteors appear to come, is quite low in the northeastern sky, even at midnight. MIDNIGHT
3 AM
6 AM
NOON
9 AM
LEO
Arcturus 10°
Regulus
12 16 0° 11
VIRGO
OPHIUCHUS
14 –10° 14 –20°
17
12 14
11
13
Spica
16
18
15 18
13 19
11 18
16 17
19
16 19
18
18 17
Antares
–30°
SAGITTARIUS
LIBRA
SCORPIUS Shaula
–40°
S
–50°
M
O
R
N
I N
G
15
K
Y
CANCER
JANUARY
21
SOUTHERN LATITUDES and its star fields and clusters can be seen with binoculars or a small telescope. If you are located around latitude 20°S the star cluster M41, near Sirius, will be directly above you. Under good conditions M41 can be seen with the naked eye.
sparkling stars, you will find the Tarantula Nebula, which appears to the naked eye as a glowing patch the size of the full Moon. Do not forget the Small Magellanic Cloud in Tucana either—it lies to the southwestern horizon this month,
Auriga is low in the north on clear January evenings and the rich Milky Way star fields of Carina and Centaurus, which are home to many interesting celestial sights, are sitting low in the southeast.
THE STARS If you are observing the skies from southern latitudes this month, you will find the bright star Canopus in the constellation Carina sitting high in the sky, while Sirius is almost overhead. Orion’s brightest stars, Rigel and Betelgeuse, are also high up. Aldebaran, the brightest star in the constellation Taurus, shines with a red-orange tint lower in the north. The star Capella in the constellation
SIGHTS OF INTEREST It is not just observers in the northern latitudes who enjoy a good view of the constellation Orion. The Orion Nebula is ideally placed high in the sky, even if you are observing from southern latitudes. The Large Magellanic Cloud in the constellation Dorado can be seen with binoculars on January evenings. Among its
CANIS MAJOR Size ranking
Brightest star
43
Alpha (α) Canis Majoris, Canis Majoris or Sirius, -1.4
Genitive
Abbreviation
Highest in sky at 10 pm
CMa
January–February 6h
7h
Sitting at the heels of Orion, Canis Major, the Greater Dog, is home to the brightest star of the entire night sky—Sirius, Alpha (α) Canis Majoris. Sirius is a brilliant white star with a magnitude of -1.4. Canis Major represents one of the two hunting dogs of Orion, the Hunter, which sits nearby. It is home to two fine open clusters, NGC 2362 and M41.
The Milky Way This view of the Milky Way shows the regions toward the constellations Crux, the Southern Cross, and Carina, the Keel.
MONOCEROS
–10º
CANIS MAJOR NGC 2360
γ
ι π
–20º
θ μ α
ORION
Sirius
ν3
β
2
LEPUS
15 M41
UW NGC
τ
ο
ο
2
1
ξ
2
2362
δ ω σ ε η
ξ
1
27
–30º
Adhara
λ
κ
ζ COLUMBA
PUPPIS
9 PM
MIDNIGHT
URANUS 6 PM
PISCES
19 18
NEPTUNE
17
Capella
16
19
15 14 13
18
17
12
16
15
11
Castor
GEMINI
13
12
11
3 PM
CETUS Pollux
14
AQUARIUS
Pleiades
TAURUS
14
ARIES
13 Aldebaran Hyades
12
PISCES
10°
Betelgeuse Procyon
Bellatrix
19
AQUARIUS
0°
11 Mira
17 17
Rigel
–10°
14 15
13 12
E V E N I N G
15
15
S K Y
11
–20°
POSITIONS OF THE PLANETS This chart shows the positions of the planets in January from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
except Mercury, the dot indicates the planet’s position on January 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Mars’s position on January 15, 2011
11
CAPRICORNUS
–30°
–40°
Neptune
EXAMPLES
11
Fomalhaut
Saturn’s position on January 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
–50°
MONT HLY SKY GUID ES: HIGHLIGHTS
JANUARY NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH The pair of star clusters NGC 884 and NGC 869 are known together as the Double Cluster. They lie in Perseus, in the northwest in January skies, and are a truly wonderful sight through binoculars or a small telescope. The constellation Ursa Minor, the Little Bear, is well placed for observation in January. In the east, the double star of Alcor and Mizar in Ursa Major, the Great Bear, can be spotted through a small telescope. Capella, in the constellation Auriga, is almost overhead.
Date
Standard time
Daylight-saving time
December 15
Midnight
1 am
January 1
11 pm
Midnight
January 15
10 pm
11 pm
February 1
9 pm
10 pm
February 15
8 pm
9 pm
Zenith 20°N
AURIGA
TAURUS
GEMINI
40ºN
Ecl ipt
Castor
ic
Pollux Capella
PERSEUS
60ºN
ARIES
CANCER
PISCES CASSIOPEIA
URSA MAJOR
Polaris ANDROMEDA URSA MINOR
Regulus Big Dipper LEO
CEPHEUS
Alcor
PEGASUS
Mizar Horiz o
DRACO Deneb
The Double Cluster Both NGC 884 and NGC 869 can be seen through binoculars or a small telescope as two fuzzy patches made of many stars, sparkling against the rich star fields of the Milky Way galaxy.
W
ES
T
BOÖTES
CYGNUS
n 20 ºN
Horizon 40ºN
o Horiz
Vega
n 60
ºN
EA
ST
HERCULES
LOOKING SOUTH The constellation Orion, the Hunter, is a magnificent sight to behold with the naked eye. Particularly striking is the color difference between Orion’s two brightest stars, the orange-red Alpha (α) Orionis, Betelgeuse, and the blue-white Beta (β) Orionis, Rigel. A telescope or a pair of binoculars will reveal the stunning Orion Nebula, M42, which sits in Orion’s sword. The variable star Mira in Cetus and the open cluster M35 in Gemini are also well placed for observation.
Zenith 60°N
Capella 40ºN PERSEUS
AURIGA
Castor Pollux
GEMINI
Propus 20ºN
TAURUS
ORION Aldebaran
ARIES
LEO CANCER tic ip
Betelgeuse Procyon
Ec l
22
PISCES MONOCEROS
Sirius
Rigel
CETUS
Regulus
Mira
HYDRA PUPPIS on Horiz
M35 in Gemini The open cluster M35 sits near the star Propus in Gemini. While a small telescope will show the cluster clearly, a larger telescope will also show the fainter cluster NGC 2158 sitting nearby.
ERIDANUS
CANIS MAJOR
60ºN
Horizon 40ºN
EA
Canopus
ST
Horiz on 20 ºN
VELA
CARINA
PICTOR
PHOENIX
W
ES
T
JANUARY
JANUARY SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The bright star Castor, Alpha (α) Geminorum, in Gemini, is an interesting target if observed through a telescope. Appearing as a single star to the naked eye, Castor is actually a multiple star system composed of six stars, three of which can be observed with a small telescope. Also on show are the open clusters M36, M37, and M38 in Auriga, the Charioteer. In the west, the prominent “V” shape of the Hyades star cluster in Taurus is a fine sight to the naked eye or through binoculars.
Zenith 40°S
ERIDANUS
CANIS MAJOR
20ºS
Rigel
Sirius 0º
ORION
PUPPIS MONOCEROS
Betelgeuse
TAURUS
CETUS
Aldebaran
Procyon
HYDRA
CANCER GEMINI
Pollux
AURIGA
ARIES
Capella
Castor
Ecl ipt ic
Regulus
Horizon 40ºS
PISCES PERSEUS LEO Horizon 20ºS
W
ES
T
URSA MAJOR
CASSIOPEIA
ANDROMEDA
EA
ST
The Hyades The “V” of the Hyades star cluster is an unmistakable sight; its members form the head of Taurus, the Bull. The bright orange-red star nearby, Aldebaran, is not actually a part of the cluster.
Big Dipper
Horizon 0º
LOOKING SOUTH The constellations Vela, Carina, and the long and winding Eridanus are all on show at this time of the year. The planetary nebula NGC 3132 in Vela is an interesting object when seen through a telescope. While you are observing the eastern part of the sky, be sure to look for the globular cluster NGC 3201. The open star cluster NGC 2547, also in Vela, is a good target for binoculars. Use a small telescope to bring into focus the scattered open cluster M47 in the constellation Puppis, the Stern.
Zenith 0°
ORION
Rigel Sirius
20ºS
MONOCEROS CANIS MAJOR 40ºS
ERIDANUS
PUPPIS
Canopus Regor PICTOR
VELA
Achernar
CARINA
PHOENIX
CETUS
HYDRA CENTAURUS TUCANA 0º izon Hor Horizon 20ºS Hor izon 40º EA S S
T
CRUX
OCTANS
AQUARIUS
β Centauri
GRUS
α Centauri
PAVO ARA
Fomalhaut
WE
ST
NGC 2547 The gorgeous magnitude 4.7 star cluster NGC 2547 sits very close to the star Regor, Gamma (γ) Velorum, in the constellation Vela. It is a fine sight through binoculars or a small telescope.
23
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
H
W
M33
M
NGU
AN
C
AS S IO
P
US
E GC 8
2
C8
03
NG 84 M1
ED
S
N
31
M
O
R M5
7
LYR A
EP H EU
M5
N
C
EIA
RS
OM
S
PE
DR 39
NU
eb
De n
CY G
4
LU
L
M
RT A
9
AC E
M2
M3
T
T
A 5
Variable star
69
CA
Vega
Globular cluster
DEEP-SKY OBJECTS Galaxy
Ca pel la
AU R I G A
MEL OPARDALIS
Polaris
U R SA MINO R
D R A CO
M92
H E RC U L E S
N ORTH
NORTH
LOOK I N G
Open cluster
Diffuse nebula
N LY
X
M13
M81
Planetary nebula
g Bi
Di
SA R U R JO A M
er pp
ar Miz M101
NA RO I S CO REAL BO
POINTS OF REFERENCE
M5
1
E ÖT
S
O
S NE IC CA NAT VE
N
I Date December 15 January 1 January 15 February 1
Zeniths
R
LEO
Daylight-saving time
TH
Standard time
Midnight
11 pm
10 pm
9 pm
20°N
Ecliptic
1 am
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
OBSERVATION TIMES
BO
M I LE O NO R February 15
Horizons 60°N 40°N 20°N
EAST
TR I A
ES
4
M87
P I SC E S
S 3
M6
4
3
M5
ASU 1
2
JANUARY | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
BE COM RE A NI CE S
3
M
ST
A
E
PE G
24
S
l Regu
LEO
S AN EXT
DR
us
AN
TL
IA
SO
U
0
PU P
CARINA
PI S
Adhara
CAN MA I S J OR
7
M5
RO S
e
P I C TO R
Canopus
IGA
des
Hya
P ERS
CU R ET I
LU M
CAELUM
S OUT H
SOUTH
LMC
DO RA D O
COLUMBA
Rigel
rix
Bellat
M42
ran
Aldeba
AU R
O R ION
M1
L E PU S
LO OK I N G
M41
Sirius
CE
5
lgeus
Bete
M3
M37
M38 M36
45
D ERI
AN
S
) es
ad
RU
lei (P
U TA
M
EUS
H
LOG O RO
US
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
IU M
ARIES
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
JANUARY | NORTHERN LATITUDES
EAST 48
SUNRISE AND SUNSET ON 15TH JANUARY
LA
M
ST
HY
I
VE
ER ANC SM
EA
67
X IS
C I AN 3
n
M9
yo M4
NO
O M
H
M
Mi
ra
NA
Zeniths
R FO
X
60°N
U
NI
SO
E HO
TU
P
X
CE
CES PI S
C
S
M44
PY
oc Pr 46
x
R
or
M
lu Pol
NO
Cast
T
A
I
TH
T 40°N
20°N
South
North
Ecliptic
LPT OR STAR MOTION
ES
IN
W
M GE
SCU
Eclipt ic
J A NUA R Y N OR T H E R N L A T IT U DE S 25
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
P IS M 33
DR
ic
AR I
ES
AN G
S
M
69
4
C8
M3
NG
TA
S
DA
Pleiad es)
UR U
M45 (
84
RSE US
C8
PE
NG
I
IA
UL UM
PE
N M10 3
ER
T
DA
RI
Ecl ipt
OM E
CA SS IO
C ET U
AN
ra
C ES 31
H
W
ES T
Mi
AS U
S
O
R T
1
2
3
4
5
Variable star
NU
S
L EP U R
S
ige l M42
M36
M37
OR ION
Capella
AU RI G A
M38
M1
Bellatrix
Aldebaran
Hyade s
C
Open cluster
Diffuse nebula
s
MAJ O R
Planetary nebula
M5
0
M
47
n
x
cyo Pro
R
tor
u Poll
I NO
Cas
C A NI S M
NI
1
X LYN
M8
8 M4
Siriu
C ANIS
Betelgeuse
M35
G E MI
DRACO
N ORTH
NORTH
LOOK I N G
AM E L OPARDALIS
Globular cluster
DEEP-SKY OBJECTS Galaxy
C ER
40°S
M44
CAN
20°S
POINTS OF REFERENCE Horizons 0°
M
67
UR
SA
M
O
R
lus gu Re
N
0°
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES Date December 15 January 1 January 15 February 1 February 15
Zeniths
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
S
R
M46
JANUARY | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
O
XT AN
NO
ST
MI
O
LE
EA
OR
LE
RA
SE
HY D AJ
PE G
26
SO
S
TH
U
EA ST
CE
C 51
US
39
NT AU R
NG
NG
A
C 32
Gac
31
rux
C
US
ux
ri
Acru x
uri
ent a
C I RC
β Ce ntau
Becr
X
LA
C RU
01
αC
32
LU P
NG
VE C 25
I NU S
IS
A
VO L
R IN
MENSA
LMC
AP U S
OCTANS
LO OK I N G
PAVO
S OUT H
SOUTH
A RA
O
RETICULUM
DOR AD
M
BA
C A ELU
COLUM
L EPUS
C HA M A E L E O N
ANS
P I C TO R
Canopus
T R IA N G U LU M AU S T R A L E
CA
PP
CA
47
M US
NG
PU
Adh ara
MA J O R
SMC
4
ANA
ar ern Ach
TU C
C 10
US
NG
H YD R
U
IU M
AN
G OLO HOR
E
D RI
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE
X
NA 40°S
NI
S
OE
U IN D
PH
FO R
X
MI
US
CR
Zeniths
GR
O
S
TU CE
S
JANUARY | SOUTHERN LATITUDES
EAST
VU
SC
U
IU
SO
OP SC
0°
U
R
TO
R CO
LP
A
M
NI S
TH
S 20°S
40°S
South
North
STAR MOTION
A
TE R CRA
LI
AU P S T IS C I R IN S US
T AN
E
S
W
3
ST
DR RIU
HY XI
QU A
PY
aut
M9
alh
41
Fom
M
CA
Ecliptic
J A NUA R Y S OU T H E R N L A T IT U DE S 27
WEST
28
MO NT H LY S KY GUID ES: OVERVIEW S
FEBRUARY To get your bearings this month, look out for the bright stars Castor and Pollux in Gemini from northern latitudes. If you are observing from the Southern Hemisphere, the constellations Carina, Puppis, and Vela can be seen high in the sky.
GEMINI Brightest stars
Genitive
Abbreviation
Highest in sky at 10 pm
30
Beta (β) Geminorum, 1.15 Alpha (α) Geminorum, 1.6
Geminorum
Gem
January–February
LYNX 6h 8h
You can find the constellation Gemini, the Twins, by looking for its two brightest stars, Beta (β) and Alpha (α) Geminorum, known to astronomers as Castor and Pollux. Castor is an interesting multiple star. You will also find the open cluster M35 near the feet of the twins.
NORTHERN LATITUDES THE STARS If you are observing the sky from mid-northern latitudes, you will find the constellation Gemini almost overhead. South of Gemini lies the sparkling Winter Triangle formed by the bright stars Sirius in Canis Major, Betelgeuse in Orion, and Procyon in Canis Minor. The four
Size ranking
constellations Taurus, Auriga, Perseus, and the W-shaped Cassiopeia are also on show this month. In the eastern sky the constellation Leo, the Lion, is visible, while the familiar shape of the Big Dipper asterism sits nearby in the northeast.
7h
Castor
30º
χ
β
φ
ο αρ
σ
θ τ ι
Pollux
υ
κ 20º
AURIGA
ε
GEMINI
δ
Ecliptic
M35
μ
ζ
η
1
ν
NGC 2392
TAURUS
81
h
Alhena
38
ξ
ORION
γ 30
10º
CANCER Procyon
Betelgeuse
CANIS MINOR MONOCEROS
SIGHTS OF INTEREST Close to the feet of Gemini, the Twins, you will find M35, a large open star cluster that can be easily spotted with a pair of binoculars. The Winter Triangle In the northern winter night sky, look out for the stars of the Winter Triangle asterism—Sirius (center bottom), the orange-red Betelgeuse (top), and Procyon (top left).
The wonderful Beehive Cluster, also known as M44 or Praesepe, is a great sight through a small telescope. It lies in the nearby constellation Cancer and appears wider than the full Moon. Meanwhile, you will find the Milky Way running through the constellation Monoceros, home to many open star clusters. If you are observing with a pair
of binoculars, look out for the star cluster NGC 2244. It is also an interesting target for a small telescope, and sits between the stars Betelgeuse and Procyon.
3AM
NOON 6AM
20° 9AM
10°
LEO
Arcturus
Regulus 12
Altair
16 0°
OPHIUCHUS –10°
VIRGO
16 –20°
13
14 15 16
16 19
19
Spica
13
14
11 16
17
12
CAPRICORNUS 11
11
14
18
17 19
15 18
18
Antares
LIBRA
–30°
SAGITTARIUS
Shaula
–40°
S
SCORPIUS
M
O
R
N
I N
G
K
Y
FEBRUARY
29
SOUTHERN LATITUDES THE STARS If you are observing from southern latitudes you will find two stellar beacons shining away high in the sky. These are the two brightest stars in the night sky—Sirius and Canopus. Two stunning constellations, Crux, the Southern Cross, and Centaurus, the Centaur, are also visible. A little way above them, you will find the deceptive False Cross, sometimes mistaken for the true Southern Cross. The False Cross is formed by four stars in Vela and Carina. At this time of the year, the two main stars of Gemini, Castor and Pollux, can be found sitting in the north. The constellations Orion and Taurus are also visible. In the south you will still find the Large and Small
Magellanic Clouds. Meanwhile Leo, the Lion, is steadily rising in the northeast.
PUPPIS
SIGHTS OF INTEREST The regions in and around the Milky Way should be explored as they contain many star clusters, such as M46, M47, NGC 2451, and NGC 2477, which can be found in Puppis. Also seek out the star clusters IC 2391 and IC 2395 in Vela and NGC 2516 in Carina.
Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
20
Zeta (ζ) Puppis, or Naos, 2.2
Puppis
Pup
January–February 7h
9h
The constellation Puppis, the Stern, is home to the open star clusters M46 and M47, which can be seen with a pair of binoculars. Puppis sits in the night sky just north of the bright star Canopus and is wedged between the constellations Vela, Carina, and Canis Major.
MONOCEROS
–10º
ORION
19
M47
Sirius
20
M46
CANIS MAJOR
16
–20º
LEPUS 11
ξ
M93
ο 1
NGC 2571
PYXIS
Adhara
3
-30º 6h
k NGC 2439
π
NGC 2451 NGC 2546
–40º
PUPPIS
Naos
The South Celestial Pole Find the South Celestial Pole by intersecting two imaginary lines: one, an extension of the long axis of Crux, and the other at right angles to the line joining Alpha and Beta Centauri.
VELA
COLUMBA
NGC 2477
σ
ν
L2 L1
V
PICTOR
–50º
CARINA
Canopus
9PM 6PM URANUS
MIDNIGHT
19
PISCES
18 17
Capella
16 15
3PM
14 13 12 11
CETUS
Castor Pollux
Pleiades
GEMINI 14
ARIES
13 Aldebaran
15
TAURUS
Hyades
CANCER
20°
12
PISCES
19
10°
Betelgeuse Procyon
17
17
Bellatrix
AQUARIUS
12 11
19
0°
15 15
Mira
13 13
Rigel
18
E V E N I N G
S K Y
–20°
POSITIONS OF THE PLANETS
Fomalhaut
This chart shows the positions of the planets in February from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
except Mercury, the dot indicates the planet’s position on February 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
19
18
17
16
15
14
13
12
11
–30°
–40° 11
AQUARIUS
–50°
EXAMPLES
11 Mars’s position on February 15, 2011
–10°
Saturn’s position on February 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125) NEPTUNE
MONT HLY SKY GUID ES: HIGHLIGHTS
FEBRUARY NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH In February, the three prominent open clusters in the northwest M36, M37, and M38 in Auriga are a must-see. Through a telescope, each cluster appears like grains of sugar scattered against the black sky; a pair of binoculars show the clusters as gray smudges. Other objects to be spotted with binoculars are the galaxy M81 in Ursa Major, the Great Bear, and the line of stars known as Kemble’s Cascade in Camelopardalis, the Giraffe, which lies close to Cassiopeia and Perseus.
Date
Standard time
Daylight-saving time
January 15
Midnight
1 am
February 1
11 pm
Midnight
February 15
10 pm
11 pm
March 1
9 pm
10 pm
March 15
8 pm
9 pm
Zenith 20°N
GEMINI
Pollux Castor 40ºN
AURIGA
Aldebaran
LEO
60ºN
Capella TAURUS PERSEUS
Eclip tic
Big Dipper URSA MAJOR URSA MINOR
CETUS CASSIOPEIA ANDROMEDA
ARIES
γ CEPHEUS
DRACO
BOÖTES Horiz on 20 ºN
PISCES
Kemble’s Cascade Sitting close to the halfway point between the bright star Capella, in Auriga, and Gamma (γ) Cassiopeiae, Kemble’s Cascade is best observed with a pair of binoculars.
Horizon 40ºN
W
ES
PEGASUS
T
Arcturus
Deneb CYGNUS
0ºN on 6 Horiz
Vega HERCULES
EA
ST
LOOKING SOUTH The open cluster M41 lies just south of the bright star Sirius in Canis Major, the Greater Dog. It is worth a look if you are enjoying the more obvious sights of Orion nearby. M41 is clearly visible through binoculars or a small telescope. To the east, the cluster NGC 2244 in Monoceros, the Unicorn, is good through binoculars and small telescopes. Also worth finding is M1 in Taurus in the west. A large telescope reveals its elliptical shape, while the biggest telescopes reveal even more details.
Zenith 60°N
URSA MAJOR
Capella 40ºN
Castor Pollux
AURIGA
GEMINI
20ºN
CANCER
LEO
Aldebaran Procyon
TAURUS
Regulus Ec lip t
30
Betelgeuse
ic
ORION MONOCEROS
HYDRA
CANIS MAJOR
Sirius Rigel
VIRGO Horizon 60ºN
ERIDANUS CETUS
PUPPIS
M1 in Taurus Also called the Crab Nebula, M1 is a supernova remnant that was formed by the explosion of a massive star. About 6,500 light-years from Earth, it appears as a faintly glowing patch in the sky.
Horizon 40ºN
EA
VELA
Canopus
ST
PICTOR CARINA
Horizon 20ºN
W
ES
T
FEBRUARY
FEBRUARY SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH In the constellation Cancer, the Crab, look out for the wonderful star cluster M44, also known as the Beehive Cluster or Praesepe. Easy to locate, it sits at the very center of the constellation, close to the stars Gamma (γ) and Delta (δ) Cancri. M44 appears as a misty patch to the naked eye from a dark sky location. Also on show, and best seen with a telescope, are the interesting spiral galaxies M65 and M66 in Leo, the Lion. These galaxies appear as elliptical smudges through a telescope.
Zenith 40°S
PUPPIS CANIS MAJOR
20ºS
Sirius MONOCEROS 0º
Rigel
HYDRA
Procyon ERIDANUS
Betelgeuse
CANCER
𝛅 𝛄
ORION GEMINI
Regulus
Eclip t
Pollux
Aldebaran
Castor
ic
LEO
TAURUS AURIGA CETUS
VIRGO Horiz
Capella
on 40
ºS
PERSEUS ARIES
W
ES
Horizon 20ºS
Big Dipper
T
URSA MAJOR o Horiz
EA
n 0º
ST
M44 in Cancer Appearing as a glittering collection of stars, the magnitude 3.7 open cluster M44 is a beautiful sight through binoculars. It is an ideal target for amateur deep-sky astrophotographers.
Polaris
LOOKING SOUTH This is a good time to observe and admire the rich star fields of the Milky Way stretching across the southern skies. To scan these stars, you only need your eyes or a pair of binoculars. Look out for the Milky Way running through the constellations Crux, Centaurus, Musca, and Carina in the east. Be sure to observe the Coalsack Nebula, a distinctive dark patch close to the stars of Crux, the Southern Cross. This dark nebula is a cloud of dust and gas about 600 light-years away.
Zenith 0°
MONOCEROS 20ºS
Sirius
ORION
CANIS MAJOR
Rigel
PUPPIS 40ºS
HYDRA
Canopus
VELA
CARINA
PICTOR
ERIDANUS
CENTAURUS CRUX
Achernar
β Centauri
VIRGO
Spica α Centauri ic ipt Ecl
ST
n 0º
CETUS
PHOENIX TUCANA
EA
Horizo
OCTANS
Horizon 20ºS
PAVO LUPUS ARA
GRUS
S n 40º Horizo
WE
ST
IC 2602 This magnitude 1.9 open cluster lying in the constellation Carina is known to astronomers as the Southern Pleiades. It is visible to the naked eye, but binoculars show it twinkling away.
31
45
AN
M3 1
PE
A
US
I OP
SE
SS
R
CA
C
Ca lla
pe
RI GA
L IS
US
Deneb
CEPH E
PARD A
AU
ME LO
M39
M52
CA
103
TA
M
884
C ER
869
NGC
NG
EIA
LA
M38
NG
O
R
PE
T
ED
34
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
X LYN
Polaris
Diffuse nebula
U R SA
M8
1
MI N
OR
Big Dip
CO
a Veg
D RA
LYRA
Planetary nebula
S U R JO A M per
10
1
RC
r
UL
iza 2
HE
M9
M
M
POINTS OF REFERENCE
ES
M
13
CO O B
N
O
R
TH
M53
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES Date January 15 February 1 February 15 March 1
Zeniths
March 15
Horizons 60°N 40°N 20°N
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
M
OM DR US
M
N 2
us
AR I E S
IA 33
S
UL UM M
GA
T
)
P IS CE S 1
tur
TR
H
W
ES
C YG N U S M29
N ORTH
NORTH
LOOK I N G
L MI EO NO R
FEBRUARY | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
ES
ÖT
ST
A
Arc
4 M6
M3
BO
E
CA V E NE S NA TIC I 51 M
A
R
ES
C BEROMA EN IC
R RE ON AL A IS
s de eia l (P
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
32
T
S
SO
U H
EA
R
ST
TE
SE
TLI
S
AN
XT AN
A
ulu s
Re g
HY DR
M6
V E LA
PY X I S
A
Ecliptic
7
M
NC
M48
ER
M93
M50
4
37
C
AJO
s anopu
r Adha
C A N ISa M
s
R
eus elg Bet
5
e
IGA
M3
AU R
M
Siriu
M41
224
S OUT H
SOUTH
VO L A N S
CA R INA
P UP P I S
M46
M47
RO S
NGC
INI
R
G EM
O MIN
MO N O C E
CAN I S
Procyon
LO OK I N G
CA
44
Pollux
Castor
6
OR
A
rix
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
O
E LU
AD
CA
M
US
T
Zeniths
s de
a Hy
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
l
LEP
ge Ri
R DO
2
N O R IO
lat Bel
ran eba
Ald
M4
MB
P I CT
COLU
M1
US AU R
M3
FEBRUARY | NORTHERN LATITUDES
EAST A
SUNRISE AND SUNSET ON 15TH FEBRUARY
GO 60°N
SO
U
ER
AN
04
ID
M1
VU
R
R CO
TH
FO
CR
E
7
40°N
20°N
South
North
STAR MOTION
W
S
TU CE
VIR US
M8
NA X
LEO
ST
M
Mira
Ecliptic
F E BRUA R Y N OR T H E R N L A T IT U DE S 33
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST M
UR US
TA
ID
ER
S
AN U
S Be
l lla tri x
O
42
N
LE
8
6
PU S
M3
AR I ES
TR
IAN GU
LU
R I GA
M
LO P A RD A L IS
Cap ella
AU
M3
M1
RI O
M
H
CA ME
lde ba ran
ya de s A
ge
45
de s)
SE U
lei a
ER
(P
P
T
Ri
US
M
N O
34
R T 2
3
4
5
Variable star
NO CE 44
GE M I NI
NGC 22
MO
Sirius
Bete lgeus e
M35
M37
Globular cluster
DEEP-SKY OBJECTS Galaxy
M50
ROS
M47
M46
n
yo Proc
R
Pollux Castor
CA NI S M I NO
Open cluster
Diffuse nebula
M
48
C AN M44
CE R
LYNX
H
M6
7
M81
Planetary nebula
s ulu g Re
AN XT
LE
O
NO
OR
MI
AJ
R
40°S
per Dip
AM
L EO
SE
URS
Big
20°S
POINTS OF REFERENCE Horizons 0°
M65 M66
iza M
r
C VE
N
O
0°
R
pt li Ec
TH
ic
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES Date January 15 February 1 February 15 March 1 March 15
Zeniths
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
CET S 1
M53
Mira
H
W
ES
D R A CO
N ORTH
NORTH
LOOK I N G
S
FEBRUARY | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
4
M6
O
RG
VI
7
M8
BE CO RE M NI A CE S
EA
ST
A N A NE S TI CI
RA YD
P IS CE
34
GO
Sp
EAST
EA ST
LU
SO
U
S
NO A
CIR
CIN US
26 02
MU S
IC
A RA
A E LEON
TO
M E NSA
LMC
PIC
R
pus
Cano
S OUT H
SOUTH
OCTANS
VO LA N S
LO OK I N G
PAVO
A PU S
C HAM
CA
T RIA NG A U S U LU M TRAL E
i
ntau r
Coa Acru Ne lsack x bul a
β Ce
rux
UX
Bec
ri
ux
Ga cr
CR
tau
en
αC
RM
S
139
RU
C5
CA R IN A
PIS
C
104
IN DU
NGC
US
S
SMC
HY DR
AN
A
LOG O RO
M
H
U EL
S
TU C
DO
CA
LUM
D ORA
PU
BA
LE
M LU CO
RE T IC U
M
AN AJ IS OR
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE
r rna he Ac
M
40°S
IU
FEBRUARY | SOUTHERN LATITUDES
ica
NT AU
NG
TER CRA
H
PU
CE
A
T
83
P UP
Adhara
M41
ID
US
PH
N
IX OE
Zeniths
GR
ER
US AN
VIR V
SO
FO
0°
R
X
U
NA
R CO
US M
VELA
IS
X
TH
S 20°S
40°S
South
North
STAR MOTION
W
04
A
SC
M1
LI
ES T
T AN
TO R
DR
TU
HY CE
PY UL P
M93
Ecliptic
F E BRUA R Y S OU T H E R N L A T IT U DE S 35
WEST
36
MO NT H LY S KY GUID ES: OVERVIEW S
MARCH As the nights grow shorter in the Northern Hemisphere, the bright winter constellations move toward the west. In the Southern Hemisphere, however, the nights are getting longer, bringing many fine celestial objects into view.
CANCER
Sextans, Crater, and Hydra. The most notable star in this part of the sky is Alphard, lying in the constellation Hydra. Appropriately, Alphard means “the solitary one.” Sitting high in the northeast is the reassuringly familiar shape of the Big Dipper asterism, with its handle arching down toward the bright star Arcturus in Boötes. A little way away and closer to the horizon lies the star Spica in the constellation Virgo. Also look
The Sickle of Leo The asterism known as the “Sickle”, made from the stars of the head of Leo, is a useful celestial signpost for navigating March’s night skies.
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
31
Beta (β) Cancri, 3.5
Cancri
Cnc
February–March
10h
You will notice that there are no very bright stars located in the constellation Cancer, the Crab. However, that does not mean you should not pay attention to it. At its heart is one of the finest open clusters in the whole of the night sky, M44, which is also known as Praesepe as well as the Beehive Cluster.
NORTHERN LATITUDES THE STARS Look north on March evenings and you will see the “Sickle” asterism, which makes up the head of Leo, the Lion. To its right is the less conspicuous constellation Cancer. Below this region are the rather faint and sparse constellations
Size ranking
8h
9h
LYNX Castor
ι
Pollux
GEMINI
γ
20º
Eclipti
CANCER M44
δ
c
ζ
Regulus
α
LEO
10º
M67
β
CANIS MINOR Procyon
HYDRA
out for the bright star Sirius shining in the constellation Canis Major near the southwestern horizon.
0º
MONOCEROS
SEXTANS
from streetlights and other sources of light pollution M81 can be spotted through a pair of binoculars. Further south, look out for the well-placed Beehive Cluster, or M44, in the constellation Cancer.
SIGHTS OF INTEREST If you are observing with a small telescope this month, be sure to look out for the magnificent spiral galaxy M81 in the northern part of the constellation Ursa Major. On a clear March evening away
MIDNIGHT
3 AM 9 AM
20°
Arcturus
6 AM
10°
Altair
AQUARIUS 0° 13 –10°
VIRGO
OPHIUCHUS 11
13
11 17
12 16 19
14
14
SAGITTARIUS
11
–20°
15 17
19 Fomalhaut
18
–30° 19
18
Spica
16 18
19
18
CAPRICORNUS
16
14
13
14
Antares
LIBRA
SCORPIUS 17
16
Shaula 15
14
13
12
11
S
AQUARIUS
NEPTUNE
M
O
R
N
I N
G
K
Y
MA R C H
37
SOUTHERN LATITUDES THE STARS If you are observing the night sky from southern latitudes, your eyes will undoubtedly be drawn to the constellations sitting in the southeast, centered around Crux and Centaurus. From mid-latitudes, you can see Alphard, the brightest star in the constellation Hydra, sitting almost right above you. Meanwhile Spica, the brightest star in Virgo, twinkles away in the east, with the blazing Canopus in Carina taking center stage in the southwest sky. The constellation
Orion is gradually sinking out of view, so make the most of it before it disappears. Leo is very much still visible and can be found sitting high in the northern part of the sky. Not far away from Leo, a little lower in the northwest, are the brightest stars of the constellation Gemini, Castor and Pollux. SIGHTS OF INTEREST You can see a great deal with a good pair of binoculars this month, including a lovely open cluster known as the Southern Pleiades, The False Cross Formed by four stars in the constellations Carina and Vela, the False Cross asterism resembles the constellation Crux, the Southern Cross, but is somewhat larger.
degrees north of the Southern Pleiades is a glowing region NGC 3372, visible to the naked eye. Also known as the Carina Nebula, it is beautiful when observed through a small telescope.
IC 2602. Its brightest member, the star Theta (θ) Carinae, can actually be seen with the naked eye. If you focus your binoculars on the cluster, you can see about 24 other sparkling stars. Around four VELA Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
32
Gamma Velorum, 1.8
Velorum
Vel
February–April
The constellation Vela, the Sails, was once part of a larger constellation called Argo Navis, the Ship. Vela can be found in the night sky near the other parts of the ship, notably the constellations Carina, the Keel, and Puppis, the Stern.
ANTLIA
PYXIS
ψ
NGC 3132
–40º
λ PUPPIS
VELA
NGC 3201
γ μ
IC 2395 NGC 3228
–50º
φ
CENTAURUS
κ
ο IC 2391
NGC 2547
δ
IC 2488
8h
CRUX
6 PM
PICTOR
9h
CARINA
VOLANS
9 PM
Acrux
10h
11h
3 PM MIDNIGHT
Capella NOON
Castor
GEMINI 30°
Pollux Pleiades 14
LEO
15
20°
TAURUS
Aldebaran
19
12
PISCES
12
Hyades
CANCER
12
ARIES
13
17
15
15
Betelgeuse
16
Bellatrix
Procyon
17
11
Regulus
10°
18 11 18
12 13
0°
Mira Rigel –10°
E N I N G E V
S K Y
–20°
POSITIONS OF THE PLANETS This chart shows the positions of the planets in March from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
except Mercury, the dot indicates the planet’s position on March 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
–30° 19
PISCES
18 17 16
15 14 13
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Mars’s position on March 15, 2011
11
CETUS
EXAMPLES
11
12
Neptune
11
Saturn’s position on March 15, 2011 The arrow indicates that the planet is in retrograde motion (see p.125) URANUS
MONT HLY SKY GUID ES: HIGHLIGHTS
MARCH NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH This month, look out for three beautiful star clusters in Taurus in the southwest: the Pleiades, M45, and the Hyades (see p.23). The Pleiades is arguably the finest open cluster in the northern skies. Although visible to the naked eye, it looks wonderful through all sorts of equipment—from binoculars to small, high-quality refractor telescopes. Other objects to spot in the vicinity are the open clusters NGC 1664 and NGC 1857 in Auriga, which are worth a look with a small telescope.
Date
Standard time
Daylight-saving time
February 15
Midnight
1 am
March 1
11 pm
Midnight
March 15
10 pm
11 pm
April 1
9 pm
10 pm
April 15
8 pm
9 pm
Zenith 20°N
LEO GEMINI
40ºN
Pollux Castor URSA MAJOR
60ºN
Big Dipper
AURIGA
Capella Ecliptic
38
URSA MINOR
Polaris
Aldebaran
Arcturus BOÖTES
PERSEUS
DRACO
CEPHEUS TAURUS
HERCULES
N on 20º Horiz
SERPENS CAPUT
CASSIOPEIA ARIES
The Pleiades Also known as the Seven Sisters, the Pleiades is a beautiful star cluster visible to the naked eye. It is a much-loved target of both astrophotographers and astronomers observing with binoculars.
Vega
Horizon 40ºN
W
Deneb
ES
Hori zo
T
n 60º N
CYGNUS
ANDROMEDA
EA
ST
LOOKING SOUTH Coma Berenices, Berenice‘s Hair, is a constellation located between Leo and Boötes in the west, and binoculars or a small telescope will reveal the scattered open star cluster known as Melotte 111, which lies within it. With a magnitude of 2.7, Melotte 111 is visible to the naked eye from a dark sky site. Other objects to look out for from northern skies include the three galaxies in Leo: M65, M66, and NGC 3628, as well as the double star Algieba, Gamma (γ) Leonis.
Zenith 60°N
URSA MAJOR 40ºN
Castor Pollux 20ºN
Algieba
GEMINI
Ecliptic
LEO CANCER
Regulus BOÖTES
Procyon MONOCEROS
Arcturus Betelgeuse
HYDRA
Aldebaran
ORION VIRGO
Horizon 60ºN
Spica
PUPPIS
Melotte 111 Also known as the Coma Star Cluster, Melotte 111 is an open cluster containing around 45 separate stars. It is a fine sight through a small refractor telescope or a pair of binoculars.
VELA
EA
LIBRA
ST
Sirius CANIS MAJOR Horizon 40ºN
Rigel
ERIDANUS
CENTAURUS
Canopus
CRUX CARINA
20ºN Horizon
W
ES
T
MA R C H
MARCH SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The galaxy M104 is an interesting target for deep-sky observers using a telescope. It sits in Virgo, the Virgin, which lies to the east in the southern skies. Also known as the Sombrero Galaxy, M104 is famous for a distinctive lane of dust that sits across its faintly glowing form. A relatively large telescope can show the dark lane clearly, but even a modest telescope reveals the galaxy’s elliptical shape. Also in Virgo is the spiral galaxy M61; however, its low magnitude (9.7) makes it difficult to spot.
Zenith 40°S
PUPPIS
20ºS
CANIS MAJOR
HYDRA 0º
Sirius
Ecliptic
Regulus
Procyon
MONOCEROS
Spica
LEO VIRGO CANCER
Rigel
Betelgeuse Pollux
GEMINI
Castor URSA MAJOR
ORION Horizon 40ºS
Arcturus Aldebaran
Big Dipper
AURIGA
BOÖTES
Horizon 20ºS
W
Capella
ES
TAURUS
T
EA
DRACO
ST
The Sombrero Galaxy M104 is a good target if you have a large-aperture telescope. This stunning image from the Hubble Space Telescope shows the prominent dust lane in great detail.
Horizon 0º
LOOKING SOUTH The globular cluster Omega (ω) Centauri is a must-see object for astronomers. A large telescope shows many of its stars, while binoculars show the cluster as a bright patch of light. In the west, the open cluster NGC 4755, the Jewel Box, in Crux, is a nice target for small telescopes and binoculars. Another western target is NGC 3372, or the Eta (η) Carinae Nebula, a little farther in Carina. NGC 3372 is visible to the naked eye against the Milky Way, with a dark lane of dust running through it.
Zenith 0°
20ºS
HYDRA
MONOCEROS PUPPIS
40ºS
Sirius CANIS MAJOR
VELA CENTAURUS
Spica
ORION
VIRGO
CARINA
Canopus
Ecliptic
CRUX
Rigel PICTOR
β Centauri LIBRA
α Centauri
LUPUS
Horizon 0º
ERIDANUS
OCTANS ARA Horizon 20ºS Achernar
SCORPIUS
EA
ST
Antares
PAVO TUCANA Horizon 40ºS
PHOENIX
WE
ST
Omega (ω) Centauri Lying 17,000 light-years away, Omega (ω) Centauri or NGC 5139 is the largest globular cluster in the Milky Way. At magnitude 3.7, it is visible to the naked eye in the constellation Centaurus.
39
AR
Hy ad es
S M
ran
NG U
LU M
AU
Ald eba
S
N
M3 6 M3 8 18
64
GC
16
1
N
GC
M3
57
7
R
M3 4
lei ad es )
TR
DR OM
PIS
(P
CE
M
ED A
SE U
A AN
PE
RI G
45
I ES 33
H
IA
W
ES T
M3
RU S
N O
R T 2
3
4
5
Variable star
pe lla
DA L
IA
IS
IO P E
M103
OP AR
4
L
C8 8
ME
Ca
CA
C
NG NG 86 9
CAS S
LY N
M81
UR SA M Polaris
CEPHE U S
M39
INO
Big Dipper
R
b Dene
N ORTH
NORTH
LOOK I N G
X
M52
L AC E RTA
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
C
M2
9
DR
NU
O AC
CYG
M
S
10
1
POINTS OF REFERENCE
LYR
A
M3
a g Ve
M9
57
2
M
April 1
March 15
March 1
February 15
Date
M
13
N
O
R
TH
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES
Arc
Zeniths
April 15
Horizons 60°N 40°N 20°N
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
UT
AP
SC
EN
RP
SE
TAU 1
ES
U M RSA AJ OR
MARCH | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
ST
A
E
UL RC
ES
ÖT BO
VE
NA T IC I r iza M
ES AN
us tur
C B O O RO R E NA AL IS HE
51 M
M1
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
40
M5
R
L IBR
A
EA
83
ST
NG C 51 39
M 10 4
SO Ga
U
NT AU
cru x
CE
VU
C RU X
M65
Ecliptic
M66
3628
ATE R
S
CR
RU S
CO R
7
3
NO
R
S OUT H
SOUTH
C A N CE
M44
P Y X IS
M67
VO L A N S
V EL A
LO OK I N G
ANT LIA
H Y D RA
NS
lus
Reg u
MI
SEXTA
L EO
O
M48
R
x llu Po
r
sto
Ca
P
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
M9
3
7
M
s
JO
R
IO
N
Zeniths
pu no Ca
NI CA a
1
OR se
A SM
M4
us i Sir
r ha Ad
50
u lge te Be
M35
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
I NA
OR
I NI
OS
M4
ER
IS UP P
M46
C AR
M
IS
N MI
GE M
C O NO
CA N
n
yo Proc
MARCH | NORTHERN LATITUDES
EAST
TH
M
ica
Sp
NGC
R
LE
CO
Be
60°N
SO
x
U
42
tri M
lla
TH
BA
VI
ge Ri
M5
M8
LU M
GO
M
S
l
40°N
20°N
South
North
STAR MOTION
W
MA E S CO NIC E B E R 64
PU
111
LE
tte
ES T
lo Me
US Ecliptic
AN
SA UR JO A M
ER ID
M1
M A RC H N OR T H E R N L A T IT U DE S 41
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
I DA NU
Rigel
Bell
H
atri x
S Ald
M42
OR 5
OS
M47
IN I
C M AN IN I S OR
GE M
M46
e M3
M4
M
5(
ad es yo n Pollux
1
tor
Cas
oc Pr
7
LI S
CE
us M3
DA
NO
N 36
Be 38
eb n
ara
pe lla
PE
RS E L OP AR
Ca
CA M
M
ge
IO M
RI
GA
tel
AU
T
M50
ES
MO
W
) des
ia Ple
EU
N O
R T
R
3
4
5
Variable star
M4 8
ER
M67
C ANC M44
H YD RA
M81
SE
AN XT
lus
u Reg
S
LEO
L EO MINO
R
Big
U R S A MA
N ORTH
NORTH
LOOK I N G
LYNX
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
J OR er Dipp
DR A
ic
M6
CA
ipt
Ecl
CO
1
BE
SV
r iza
EN
40°S
M
NE
20°S
POINTS OF REFERENCE Horizons 0°
4
I
M6
IC AT
51
01
M
M1
N
O
0°
R
Standard time
Midnight
1 am
Daylight-saving time
TH
Midnight
11 pm
40°S
9 pm
10 pm
11 pm
9 pm
8 pm
20°S
Ecliptic
10 pm
OBSERVATION TIMES Date February 15 March 1 March 15 April 1 April 15
Zeniths
M5
ER S
2
EAST
Hy
US 1
53 M
Spica
GO VI R
04 M1
R AT E
CR
MARCH | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
ur
ES
Ar ct
us
ST
A
E
ÖT BO
3 M
87 M
CO RE MA NI CE S
R TAU
42
GO LU
RA
M4
O SC
Ant
M6
are
s
2
US
SO
U
A
TE
RM
LE SC OP
51
A
I UM
AR
uri
39
en ta
C
TA U S
aur i
X
S
4755
CI N U
ent
CIR
βC
NGC
CRU
Be cru x
ru x
Ga c
RU
TR I AN AU GULUM ST R AL E
EN
DRA
A
4
T U CA N
C 10
SMC
HY D R
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
ICU
M41
S
M LU
NI
Horizons 0°
20°S
EL
UM
UM
CA
Zeniths
X
GI
NI
O OL
E HO
40°S
P
r rna he Ac
R
AD
HO
R DO
O
BA
M LU CO
S 0°
SO
PU
LE
Sirius
OR
AJ M
POINTS OF REFERENCE
RET
R
s
CA
opu
TO
Can
Ad ha ra
PI C
P IS
US
PU P
LMC
A
SA MEN
NG
VO L A N S
C A RIN
S OUT H
SOUTH
I ND US
O CTANS
C H AMA E L E O N
MU S C A
V ELA
LO OK I N G
PAVO
APU S
Acru x
NGC 3372
TLIA
M93
MARCH | SOUTHERN LATITUDES
ST
NO
αC
NG
HY
AN
U
TH
X
NA
EAST
0
FO R
M8
T
LIB
I RP
EA
S
83
TH
la
au
Sh
PU
US 20°S
40°S
South
North
STAR MOTION
ES
M
E
US
AN
VIR RI D
V COR
C
W
PYXIS
Ecliptic
M A RC H S OU T H E R N L A T IT U DE S 43
WEST
44
MO NT H LY S KY GUID ES: OVERVIEW S
APRIL Although the nights in the Northern Hemisphere are getting shorter, there is still plenty of time to do some serious sky gazing. In the Southern Hemisphere there is plenty to see, including the magnificent arc of the Milky Way sweeping across the sky. NORTHERN LATITUDES THE STARS The magnitude -0.1 star Arcturus in Boötes sits in the west this month, and should be one of your first signposts. Find it by following the curve of Ursa Major’s handle, away from its “bowl.” Along this curve, past Arcturus, you will eventually
come across the bright star Spica in Virgo. Not far away from Virgo is Leo, and below these two constellations is a relatively empty patch of sky containing the long constellation Hydra, the Water Snake. SIGHTS OF INTEREST If you are using binoculars the Coma Star Cluster in the constellation Coma Berenices is a beautiful object to observe on a clear April night. Look out for the spiral The Big Dipper The famous asterism known as the “Big Dipper” sits high in the sky this month. It is part of the constellation Ursa Major, the Great Bear, and is sometimes referred to as the Plough.
40°
30°
9 AM
20°
LEO Size ranking
Brightest stars
Genitive
Abbreviation
Highest in sky at 10 pm
12
Alpha (α) Leonis 1.4, Beta (β) Leonis 2.2
Leonis
Leo
March–April
The constellation Leo, the NES VENATICI Lion, lies between Cancer and Virgo. It is familiar to deep-sky observers because 30˚ it is home to many interesting galaxies. These include the galaxies M66, M65, and M96, which are 20˚ excellent targets for an amateur telescope. The constellation’s brightest star is Regulus, Alpha (α) 10˚ Leonis, which sits at the bottom of the famous backwardquestion-mark-like 0 ˚ “Sickle” asterism.
-10
10h
11h
LYNX URSA MAJOR
LEO MINOR
κ
μ ζ
54
72
δ
93
60
Algieba
ε γ
THE SICKLE
40
θ
β
tic
M105 M96
ι
χ∴ σ
η
LEO
NGC 3628
M65 M66
Denebola
λ NGC 2903
Eclip
α
Regulus
R
M95
31
ρ
π
ξ
ο 10
59 58
τ
HYDRA
NGC 3521
VIRGO
υ 87
φ
61
SEXTANS
˚
galaxy M81 in Ursa Major with a small telescope. With a large telescope you can seek out the Virgo Cluster, which contains many faint but interesting galaxies.
CRATER
star Vega, in Lyra, is highest in the sky. Although this shower does not create many meteors, they can be quite bright and fast; you can expect to see around 10 meteors over the course of an hour.
METEOR SHOWER The Lyrid meteor shower is best seen from northern latitudes and reaches its peak around April 21–22. The best time to view it is around dawn, when the bright
MIDNIGHT
3 AM
6 AM
Arcturus
PISCES 10°
13 11 11
Altair
16 18
0°
17
AQUARIUS
12 19
VIRGO
OPHIUCHUS
11 19
–10°
12
14
CAPRICORNUS
14 15
–20° 19
18
18
17
16 19
16
18
13
LIBRA
Antares 19 18
Fomalhaut
PISCES
17 16 15
14
19
18
17
16
15
14
SAGITTARIUS 13
13
12
SCORPIUS Shaula
11
12 11
AQUARIUS CETUS
URANUS
NEPTUNE
G I N N R M O
S
K
Y
A P R IL
45
SOUTHERN LATITUDES THE STARS As the skies get dark you will notice that the constellations scattered along the arc of the Milky Way come into view. In the Southern skies, Crux, also known as the Southern Cross, and Centaurus, with the bright stars Rigil Kentaurus and Hadar, or Alpha (α) and Beta (β) Centauri, are visible. In the southeast, do not miss the bright star Antares in Scorpius. On the opposite side of the sky, you will see Canopus in Carina.
SIGHTS OF INTEREST This time of year is perfect for observing the dark nebula known as the Coalsack. You will find it nestled within the rich, bright star fields of the Milky Way. It is easily visible to the naked eye, sitting right next to Crux, or the Southern Cross. The Coalsack appears dark because it stops the light from the stars behind it from getting to our eyes. Not far from the Coalsack you will find the wonderful open cluster NGC 4755, the Jewel Box Cluster. It looks like a hazy star to the naked eye,
The Coalsack This dark nebula can be seen near Crux, the Southern Cross, with the naked eye. It is a vast dust cloud that blocks the light from the stars behind it.
NGC 3372, the Carina Nebula. The real star of the show is the stunning globular cluster NGC 5139, Omega (ω) Centauri, in the constellation Centaurus. A small telescope reveals many of its millions of stars.
but binoculars or a small telescope will reveal its individual stars. If you are observing with binoculars, make sure you do not miss two marvelous sights in the nearby constellation Carina—IC 2602, or the Southern Pleiades, and
There is relatively little going on in the sky overhead—this area is dominated by the long and winding constellation Hydra. However, you will find the bright star Spica in Virgo high in the east.
C RU X Size ranking
Brightest stars
Genitive
Abbreviation
Highest in sky at 10 pm
88
Acrux 0.8, Becrux, or Mimosa, 1.3
Crucis
Cru
April–May
Of all the constellations Crux, the Southern Cross, is the smallest. The whole constellation should fit behind your outstretched hand at arm’s length. You can use two of the bright stars that make up Crux to trace a line in the approximate direction of the South Celestial Pole.
VELA –50º
CENTAURUS
–60º
μ γ CRUX δ λβ ε NGC ι β Centauri 4755 Coal- α θ1,2 sack Acrux ζ η
CARINA
MUSCA –70º
6 PM
12h
13h
14h
11h
3 PM
NOON
9 PM
Capella 40° MIDNIGHT
Castor
30°
GEMINI
Pollux
Pleiades
12 14
13 19
17
LEO
15
Aldebaran
12 Regulus
CANCER
20° 18
TAURUS
Hyades
16
ARIES
16
15
15 12
13
Betelgeuse Procyon
17 10°
Bellatrix 0°
11
14
Mira Rigel
17
–10°
Spica –20°
POSITIONS OF THE PLANETS
S
E
V
E
N
I N
G
K
Y
This chart shows the positions of the planets in April from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
except Mercury, the dot indicates the planet’s position on April 15. Mercury is shown only when it is at greatest elongation (see p.125). For the specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
Mars’s position on April 15, 2011
11
Saturn’s position on April 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
MONT HLY SKY GUID ES: HIGHLIGHTS
APRIL NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH Northern skies in April contain the open cluster NGC 188 in the constellation Cepheus. This cluster sits just south of the bright star Polaris, Alpha (α) Ursae Minoris, and is a nice target for a large telescope. For observers using binoculars, the open clusters M36, M37, and M38 in the constellation Auriga are still on show, as is the Double Cluster (see p.22) and the double star Mizar and Alcor. Also look out for the spiral galaxy M81 in the constellation Ursa Major.
Date
Standard time
Daylight-saving time
March 15
Midnight
1 am
April 1
11 pm
Midnight
April 15
10 pm
11 pm
May 1
9 pm
10 pm
May 15
8 pm
9 pm
Zenith 20°N
Regulus 40ºN LEO
Arcturus
URSA MAJOR
Alcor
60ºN
CANCER
Big Dipper Ecliptic
46
BOÖTES
Mizar
Pollux Castor URSA MINOR
HERCULES
Polaris GEMINI
DRACO
CEPHEUS AURIGA
Capella Horizon 20ºN
Vega
ORION
OPHIUCHUS
Betelgeuse Deneb
PERSEUS
M36 in Auriga The open cluster M36 is a truly wonderful sight when seen through a small telescope. It sits in the middle of Messier’s three famous open clusters in Auriga.
CASSIOPEIA
Aldebaran
W
Horizon 40ºN CYGNUS
ES
T
TAURUS
EA ANDROMEDA
ST
Horizon 60ºN
LOOKING SOUTH There is a lot to see in April for deep-sky and galaxy enthusiasts looking south. Virgo has galaxies that can be seen through a telescope, such as M84, M86, and M87. The globular cluster M3 in Canes Venatici, the Hunting Dogs, makes a good small-telescope target. Canes Venatici can be located between Ursa Major and Boötes high in the northeast of the April skies. A small telescope will help show the lovely open cluster M48 in Hydra, the Water Snake. M48 is a loose collection of 80 stars southwest of Hydra‘s head.
Zenith 60°N
URSA MAJOR 40ºN BOÖTES
20ºN LEO
CANCER
Arcturus
Castor Pollux Eclipt i
Regulus
c
VIRGO GEMINI HYDRA
Spica
SERPENS CAPUT
Procyon MONOCEROS
LIBRA OPHIUCHUS
The Virgo Galaxy Cluster Lying in the constellation Virgo, this cluster is thought to consist of an incredible 2,000 individual galaxies. Several of its brightest members can be observed using amateur equipment.
Horiz o
CENTAURUS PUPPIS
Horizon 40ºN LUPUS
EA
ST
SCORPIUS
β Centauri α Centauri
n 60
ºN
Sirius
VELA
CRUX
Antares
CANIS MAJOR
20 zon Hori
CARINA
ºN
W
ES
T
A P R IL
APRIL SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH In the west, Leo plays host to many interesting galaxies that can be seen with relatively modest amateur equipment. The spiral galaxies M65 and M66 can be spotted with a small telescope, while M96, M95, and M105 are excellent targets for large-aperture telescopes. They are found clustered around a region at roughly the halfway point between the stars Chertan, or Theta (θ) Leonis, and Regulus, or Alpha (α) Leonis. M65 and M66 appear as gray smudges of light through a small telescope.
Zenith 40°S
20ºS
HYDRA
Spica
Eclipti
0º PUPPIS
c
VIRGO
Regulus
Chertan
LIBRA
LEO
Arcturus
Procyon CANCER
URSA MAJOR
SERPENS CAPUT
BOÖTES
MONOCEROS
40ºS Horizon
Pollux
OPHIUCHUS
Castor Big Dipper Betelgeuse
W
HERCULES
GEMINI
Horizon 20ºS
ORION
ES
DRACO
T
EA
AURIGA URSA MINOR
Horizon 0 º
ST
M66 in Leo The magnitude 8.9 spiral galaxy M66 appears in the bottom right of this image as part of the famous trio of galaxies known as the Leo Triplet, which also includes M65 and NGC 3628.
LOOKING SOUTH By far the most impressive sight from southern latitudes is the great arc of the Milky Way galaxy. It stretches all the way from the magnificent region in the east around the constellations Scorpius and Sagittarius, through Crux, Carina, and Vela down to Puppis and Canis Major. The bright, magnitude 0.8 star Acrux, or Alpha (α) Crucis, in Crux is a multiple star that can be resolved by a small telescope. The galaxy M83 in Hydra is an excellent large-aperture telescope object.
Zenith 0°
20ºS
Spica
VIRGO
HYDRA
c
𝛄 Ecli pti
40ºS
LIBRA
CENTAURUS
θ Centauri
CRUX
VELA
Acrux β Centauri LUPUS
SCORPIUS
PUPPIS MONOCEROS
α Centauri
CARINA
ARA
OPHIUCHUS
Canopus
Horizon 0º
OCTANS
CANIS MAJOR
Sirius
PICTOR
PAVO ORION
Horizon 20ºS
EA
SAGITTARIUS ERIDANUS
ST
Achernar TUCANA
Horizon 40 ºS
Rigel
WE
ST
M83 in Hydra The spiral galaxy M83 sits in the constellation Hydra. It can be found in the night sky sitting between the stars Menkent, or Theta (θ) Centauri, and Gamma (γ) Hydrae.
47
MO NT H LY S KY GUID ES: SKY GUID ES
WEST H
W
rix M3
A
GA
IN I
UR I
elge use M
st 4
CA
U TA
RU M4
S 5(
M3 3
M3
lla
or
UM
Ca pe
Ca
37
GU L
Pollux
M
38
IA N
EU S
TR
RS
M
PE
GEM
5
36
ES T
bara
des n
) des
ia Ple
M1
N O
R T 4
5
Variable star
ME
L
884
LI S
LYN X
OP A
RD A
NGC
NGC
M10
869
3
UR S A MA J O R
CA SS I O
M81
EDA
P EI A
A N D RO M M31
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Big
URSA
C 18 8
Polaris NG
NE I CA AT N VE
L AC E R
CEPHE US
OR
per
Dip
MI N
M52
NORTH
N ORTH
Diffuse nebula
Planetary nebula
DR
TA
O AC
BO
ÖT
b ne De
POINTS OF REFERENCE
M39
ES
C
M
13
ga Ve
A
US
R LY
GN CY 29
May 1
April 15
April 1
March 15
Date
N
O
R
TH
11 pm
10 pm
9 pm
8 pm
60°N
V
40°N
Midnight
Standard time
OBSERVATION TIMES
M
IS EAL Zeniths
May 15
Horizons 60°N 40°N 20°N
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
US
Bet
Hya
Alde
3
LA
CH
HIU
OP
er
ng
llat
2
UL
PE
CU
ha
at
Co
Be
1
Al
re o
ST
A
E
ES
UL RC
HE
N 0
STAR MAGNITUDES -1
bi
57 M
M
APRIL | NORTHERN LATITUDES
LOOK I N G
ar
OR
AB ON OR 92 M
CI
iz
51
1 10 M
S
M
OR I O
48
S
M8
M10
Ant
are
0
M4
US
TH
LI
EA
BR A
UP
L
ST
US
5
SO
U
Ecliptic
VI
3
O
M8
RG
ntau ri
β Ce
5139
TAU RU
NGC
C EN
a
Spic
M86
M84
M104
M87
CRATE
I
R
M
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
u
A
D HY
67
RA
M
44 M
C
ER
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
A
VE L A
A N TL I
g Re
CA RIN
S AN S EX T
LEO
lus
C AN
P
S
48
Zeniths
I YX
M
yo
n Pr oc
R
S OUT H
SOUTH
C RU X
LO OK I N G
Acrux
Gacrux
CORVU S
64
Becrux
S
M
O LE
GE M
I
IN
S M
46
NI
P
U
60°N
SO
PU
CA
OR
IN M
NO
APRIL | NORTHERN LATITUDES
EAST
s
M
M1
PI
S
OR SC
PI
ON M
47
M
U UC2H M
TH
93
T CA
us
1
Siri
us
0
S 40°N
20°N
South
North
STAR MOTION
E
ur
W
PU RO
OP HI
CA
OC E
S ct Ar M5
EN ES NI
SERP
ÖT 53
ST
BO M
OR
3
SM AJ
M M4
BE
Ad har a
CO RE MA NI CE S
U MA R S A JOR
Ecliptic
A PR IL N OR T H E R N L A T IT U DE S 49
WEST
lgeu
N MO OC
OR I O M3
CA NI SM
IN
I
Pr oc y on
Ca st or
Po
M48
llu x
CA ER
X
M6 7
NS
L EO
M95
LEO
OR
AT E
M96 M105
R
M66 M65 628 NGC 3
A JO R Big Dipper
N 5
OS
R AU
IG A
N O
R T
RA
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
COR
VU
S
M8
7
Planetary nebula
4
VI R
M6
GO
S
M
53
a M1
M51
ICE
Spic 01
lip
tic
rus ctu Ar
Ec
M3
Horizons 0°
20°S
POINTS OF REFERENCE
ER EN
r
T I CI VE N A
COMA B
C A NE S
Miza
DRACO
U R S A M I NO R
N ORTH
NORTH
LOOK I N G
UR SA M
MIN
s
Regu lu
A XT
4
NC
M4
LY N
CR
IN
OR
EM
G
W
T
SE
ER
H
ES
HYD
se
2
BO
ÖT
40°S
Date
N
O
NA S RO LI CO R E A BO
March 15 April 1 April 15 May 1 May 15
0°
R
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
ES
M5
Zeniths
S
Bete
1
ES
UL
RC
1 am
Midnight
11 pm
10 pm
9 pm
40°S
Ecliptic
Daylight-saving time
HE
EAST
2
M1
O
I PH
UC
13
M
T PU
CA
S EN RP
SE
4 10 M
APRIL | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
ST
A
E
HU
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
50
80
S M
M2
M9
3
M24
S
M
1
19 M
M2 6
M
M2
7
8
8
2
M6
9
M5
4
SA
G
AR ITT
IU
EA
S
H
ST
A ON ALI R CO STR AU
T
TE LE
US
SC OP
PI
IU
S
A
DU
RM
IN
A
NO
AR
M
RA
SO
U
TRI ULU
S
M AU
PAV O
ANG
CI N U
i
aur
CIR
ent
αC
139
SMC
IA
PHO E N
US HY DR
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
C
RE
OR
LU T I CU
P I CT
r rna he Ac
LMC
NS
M
Horizons 0°
20°S
POINTS OF REFERENCE
IX
A
P
IS
YX NA A RI
VOLA
V EL A
TL
MENS
AN
S OUT H
SOUTH
NGC 104
OCTANS
C H AMA E L E O N
TU CA NA
AP US
MU S C A
Acrux
LO OK I N G
LE
RA
Gacrux
RU S
C RU X
Becrux tauri
β Cen
C5
S TR A
NG
NT AU
HY D
APRIL | SOUTHERN LATITUDES
EAST
M2
au l
SC OR
es ar a
t An 62
US
CE
S
R
40°S
HO
UM
O
0°
I
SO
ER
N
U
ius
TH
US
M LU
CA
N DA
E CA
B
A
7 M4
M LU CO
Zeniths
GI
AD
O OL
R DO
s
IS
pu
PP
no Ca
PU
6 M4
3 M9
ra ha Ad
M50
41 M
VU Sir
IS
HU OR
AJ
OP
C H IU
M
0
T
M 4
Sh
M M
UP
L
S 20°S
40°S
South
North
STAR MOTION
ES
M1 3
W
LIB
PU
C
LE
M8
ION Ecliptic
OR
OR
A PR IL S OU T H E R N L A T IT U DE S 51
WEST
52
MO NT H LY S KY GUID ES: OVERVIEW S
MAY In the Southern Hemisphere you will be treated to the richness of the constellations Centaurus, Scorpius, and Sagittarius. If you are observing from the Northern Hemisphere, you will see more subdued constellations, such as Hercules and Virgo.
C O M A B E RE N I C E S Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
42
Beta (β) Comae Berenices 4.2
Comae Berenices
Com
April–May
curving handle to find your way to Arcturus in the constellation Boötes. To its south, you will see the bright star Spica in Virgo. This month the
14h
37
β
50°
30°
16 14
31
NGC 4565
23
M64
20º
111 12 7
FS
BOÖTES
35
Arcturus
M53
α COMA BERENICES
M85
36 M91
LEO
11 M100
M88
M98 M99
10º
VIRGO
Finding the Pole star You can use the stars Alpha (α) and Beta (β) Ursae Majoris (right) in the Big Dipper asterism to find the location of the pole star, Polaris (center top).
40°
γ MELOTTE
41
bright blue-white star Vega rises in the east in the constellation Lyra, the Lyre—a celestial sign that summer is on its way. If you are observing the night sky from lower northerly latitudes, you can also glimpse the constellation Scorpius, the Scorpion, peeking over the southeastern horizon, led by the bright orange-red star Antares.
NOON
12h
13h
The constellation Coma Berenices, the Hair of Berenices, is not very prominent in the night sky. However, it does contain a wonderful binocular target, the magnitude 2.7 open cluster Melotte 111 (also known as the Coma Star Cluster), as well as the interesting galaxy M64, or the “Black Eye” Galaxy.
NORTHERN LATITUDES THE STARS If you have a small telescope, point it at the middle star in the “handle” of the Big Dipper asterism in Ursa Major. This is the star Mizar, which has a companion star, Alcor, that can be glimpsed with the naked eye. A closer inspection of Mizar with a telescope shows that it is made up of a pair of stars. Once again, follow the Big Dipper’s
Size ranking
SIGHTS OF INTEREST For galaxy enthusiasts, the May night sky offers two relatively bright targets. The first is the Whirlpool Galaxy, or M51, in Canes Venatici. The second is the spiral galaxy M101, which sits to the north of the Big Dipper’s handle. METEOR SHOWER The annual Eta Aquarid meteor shower peaks this month. Because the radiant of the shower lies near the celestial equator, it is not a great sight from far northerly latitudes.
6 AM
ARIES
MIDNIGHT
20° 3 AM
16
12
11
11
10°
PISCES
11 17 19
Altair 11
13
17
AQUARIUS
14
0°
OPHIUCHUS
Mira –10°
18
19 18
URANUS
17 19
19
19 18
PISCES
17 16 15
14
15 16
16 Antares
CAPRICORNUS 18
17
16
15
14
SAGITTARIUS 13
13
12
SCORPIUS Shaula
11
12 11
AQUARIUS CETUS NEPTUNE
M O R N I N G
Y S K
MA Y
53
SOUTHERN LATITUDES THE STARS Sitting high in the southern sky is the prominent constellation Crux, the Southern Cross. If you have a small telescope, be sure to point it at Crux’s brightest star Acrux, Alpha (α) Crucis, which is actually a double star made of two blue-white stars. The Milky Way rises high in the south this month, with Sagittarius and Scorpius sitting in the east— a clue that winter is on its way in the Southern Hemisphere. SIGHTS OF INTEREST Whether you are observing with the naked eye or a telescope, it is the globular cluster NGC 5139, Omega (ω) Centauri, you will want to focus on this month. You can see it easily as a hazy star with the naked
eye, whereas a telescope reveals many of its millions of stars in a tight ball. If you have a large-aperture telescope, turn it toward the fine spiral galaxy M83 that sits in the constellation Hydra.
C E N T A U RU S Brightest stars
Genitive
Abbreviation
Highest in sky at 10 pm
9
Alpha (α) Centauri -0.3, Beta (β) Centauri 0.6
Centauri
Cen
April–June
LIBRA The large constellation Centaurus, the Centaur, sits within the –30º rich star fields of the Milky Way. It is home to what is arguably the finest globular cluster in –40º η the whole night sky—the magnificent Omega (ω) LUPUS Centauri, or NGC 5139. The constellation’s two brighest stars are Alpha (α) and Beta (β) Centauri, known more familiarly to astronomers as Rigil Kentaurus and Hadar. CIRCINUS The constellation is fully visible between the latitudes of 25°N and 90°S.
METEOR SHOWER Caused by the dust left over from Comet Halley entering our atmosphere and vaporizing, the Eta (η) Aquarid meteor shower peaks every year around May 5–6. You can expect to see roughly 30 meteors an hour. The meteors appear to be coming from a point near the star Eta (η) Aquarii, in Aquarius, and tend to be quite fast moving. The farther south you are, the better view of the shower you will get. Spectacular star fields Looking into the southern night sky in May, you cannot miss the bright stars Alpha (α) and Beta (β) Centauri (left). Nearby you will find the constellation Crux (right) and the Coalsack Nebula.
Size ranking
13h
14h
12h
11h
CORVUS HYDRA 4 1 2
3
ANTLIA
θ
CENTAURUS
ψ
φ ν μ υ1
χ υ2
NGC 5128
ζ NGC 5139
NGC 5460
ω
NGC 4945
ξ
1
ξ
2
γ
τ
σ ρ
ε
VELA
δ
NGC 3918
CRUX
ο1,2
(β) centauri
R
π
NGC 3766
(α) centauri Acrux
λ
MUSCA
TRIANGULUM AUSTRALE
CARINA
3 PM NOON 6 PM
50°
Capella
40°
9 PM
Castor Pollux
12
GEMINI
MIDNIGHT
14 19 18
15 14
CANCER 15
LEO
Arcturus
30°
TAURUS 13
Pleiades 15 13
17
15
20°
Aldebaran Hyades
12
10°
Regulus
Betelgeuse
16 Procyon
Bellatrix 0°
11 14
VIRGO
17 12
Rigel –10°
13
Spica
14 18
LIBRA POSITIONS OF THE PLANETS
S
E
V
E
N
I N
K
Y
This chart shows the positions of the planets in May from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
G
except Mercury, the dot indicates the planet’s position on May 15. Mercury is shown only when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
Mars’s position on May 15, 2011
11
Saturn’s position on May 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
MONT HLY SKY GUID ES: HIGHLIGHTS
MAY NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH The globular cluster M13 in Hercules is a prominent feature in May. It is located roughly a third of the way along a line between the stars Eta (η) and Zeta (ζ) Herculis. Although M13 can be seen with binoculars, a telescope shows it more clearly. Larger aperture telescopes can show a multitude of the cluster’s stars. Another object to look out for is the planetary nebula NGC 6543 in Draco, which is best suited to larger telescopes.
Date
Standard time
Daylight-saving time
April 15
Midnight
1 am
May 1
11 pm
Midnight
May 15
10 pm
11 pm
June 1
9 pm
10 pm
June 15
8 pm
9 pm
Zenith 20°N
40ºN
URSA MAJOR
LEO
BOÖTES
60ºN
HERCULES
ζ
η
Big Dipper DRACO
URSA MINOR
Ecliptic
54
ψ Draconis Vega
CANCER
Pollux
CYGNUS
CEPHEUS
Castor
Deneb GEMINI
on 2 0ºN
AQUILA
Capella
Procyon
NGC 6543 This magnitude 8.1 nebula, also known as the Cat’s Eye Nebula, is best suited for larger telescopes and appears as a bluish disk. It is 3,600 light-years away from Earth.
Horiz
CASSIOPEIA
AURIGA
Horizon 40ºN
W
ES
ANDROMEDA zon Hori
T PEGASUS
PERSEUS
Altair
N 60º
EA
ST
LOOKING SOUTH There are several notable globular clusters worth observing in May’s night sky. M10 in the east, at the heart of the constellation Ophiuchus, is visible with binoculars. Just northwest of M10 but also in Ophiuchus lies another cluster, M12, which is a fine sight through a small telescope. Moving up a little, the globular cluster M5 appears over the border in the southern part of Serpens Caput, the Snake’s Head. Kappa (κ) Boötis is a double star in Boötes, visible through a small telescope.
Zenith 60°N
κ
URSA MAJOR 40ºN
BOÖTES
20ºN
Arcturus HERCULES
LEO SERPENS CAPUT
Ecliptic VIRGO
Spica
OPHIUCHUS LIBRA SERPENS CAUDA
CANCER
Regulus
HYDRA
Horiz on
Antares LUPUS
M10 in Ophiuchus The magnitude 6.6 globular cluster M10 lies 14,000 light-years from Earth, and is a little over 80 light-years in diameter. It is a wonderful target for a small amateur telescope.
CENTAURUS
EA
60ºN
Horizon 40ºN
SCORPIUS
SAGITTARIUS
β Centauri
ST ARA
α Centauri
CRUX VELA
o Horiz
ºN n 20
W
ES
T
MA Y
MAY SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH In the east, several star clusters are on view in the constellation Ophiuchus this month. Besides the globular clusters M10 and M12, there is the magnitude 4.6 open cluster NGC 6633, roughly the same size as the full Moon on the sky. Composed of 30 stars, this open cluster is a wonderful sight through a small telescope. Northwest of NGC 6633 is another large and scattered open cluster, IC 4665, which lies close to the star Cebalrai, or Beta (β) Ophiuchi, and is easily visible with binoculars.
Zenith 40°S
CENTAURUS
20ºS
HYDRA
SCORPIUS
Spica Antares LIBRA
0º VIRGO
OPHIUCHUS SERPENS CAPUT
Arcturus
LEO
SERPENS CAUDA
BOÖTES
Cebalrai
Regulus Eclip tic
HERCULES n 40ºS Horizo
CANCER
URSA MAJOR
Big Dipper DRACO
Horizon 20ºS
W
ES
Vega
Pollux
T
Horizo n0
EA
URSA MINOR
º
ST
M12 in Ophiuchus Discovered in 1764 by Charles Messier, M12 is a prime target for a small telescope. It is estimated to be between 16,000 and 18,000 light-years away from Earth.
LOOKING SOUTH The beautiful section of the Milky Way around Crux, the Southern Cross, including the dark nebula known as the Coalsack, takes center stage in the south in May. There are several fine open clusters on view in Carina, many nestled among the rich star fields of the Milky Way. NGC 3532 can be seen with the naked eye, but binoculars reveal its many twinkling stars well. The magnitude 4.2 cluster NGC 3114 is an interesting target for a small telescope, while NGC 2516 is a good target for binoculars.
Zenith 0°
VIRGO
Spica 20ºS LIBRA
OPHIUCHUS
Ecl ipt ic
40ºS
LUPUS
β Centauri
SCORPIUS
α Centauri
SERPENS CAUDA
HYDRA
CENTAURUS
Antares
CRUX VELA
ARA CARINA SAGITTARIUS Horizon 0º
Avior PUPPIS
PAVO OCTANS PICTOR Horizon 20ºS
EA
Canopus
CANIS MAJOR
TUCANA
ST
Sirius
GRUS
Achernar PHOENIX
Horizon 40ºS
WE
ST
NGC 2516 The magnitude 3.8 open cluster NGC 2516 sits roughly 3.5 degrees away from the star Avior, Epsilon (ε) Carinae. It contains roughly 100 stars and can be viewed with just a pair of binoculars.
55
MO NT H LY S KY GUID ES: SKY GUID ES
WEST GE UR I GA
N
I NX
IN Cap ella
LY
M
M
I M
A 38
st or
M
O
44
M
T
Ca
lu x
Po l
M 36
ES
LE
ER 37
H
W
35
N O
R T 3
4
5
Variable star
OR
U
RS
AM A
J OR
SEU S
M81
69
M51
Mizar
NGC 8
C VE A N E N AT S I CI
r
pe
ip
gD
Bi
IS
4
Polaris
M101
DRA
CO
C A SS I O P E I A M103
A N D R O M E DA
LOOK I N G
BO
ÖT
N ORTH
NORTH
T R I A N G U LU M
NGC 88
CA M ELOP A R DA L
PE R
M34
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
ES
LAC
POINTS OF REFERENCE
EUS
NGC 6543
2
M13
CY
SU
S
b ne De
GA
GN
US
M
29
N
R
bir eo
O
Al
June 1
May 15
May 1
April 15
Date
Zeniths
TH
A
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES
PE
9
TA
M3
ER
a
June 15
Horizons 60°N 40°N 20°N
CE P H
M5
M31
Planetary nebula
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
M
M1
2
Altair
UL RC HE
ILA
AQ U
GIT
SA
CA NC
I NO R 1
er
ng
CAN IS M 0
STAR MAGNITUDES -1
VU
LP
EC
UL
ha
7
57 M
TA
S
I NU
LP H
DE
Ve g
A
92 M
ES
LY R
at
M2
Co
ST
A
E
R NO MI
SA UR
MAY | NORTHERN LATITUDES
Procyon
56
N
M1
1 M
M2 14
6
U DA S CA
M
M1
6
M1
M
M2
5
18
M2
M2
4
2
21
M
M2
8
8
M
7
SO
U
SUNRISE AND SUNSET ON 15TH MAY
7
M
23
6
tar es
AR A
SC OR
An
PI
US
M4
0
NO
M8
RM A
NS
M5
US
US
LI B R
LU P
T
C IN
PU
C IR
CA
A
α Centauri
M64
x Acru
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
x Gacru
U CORV
M87
S OUT H
SOUTH
C RU X
Becrux
M104
VIRGO
M53
CENTAURUS
M83
Spica
β Centauri
Arcturus
LO OK I N G
Ecliptic
A
S
COMA S CE BE R EN I
MAY | NORTHERN LATITUDES
EAST M
ST
US 9
S
EA
62
CH M1
R
TH
la
M
U HI au
9
OP 12
LE
Sh
M
M
U RC 10
PE
IS
N RO A L CO RE BO
M
SE
O LE Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
S
TER CRA
lus
S
LA
Zeniths
VE
AN XT
Reg u
SE
AN
TL
A
SO
U
60°N
I
M67
RA
TH
HY D
SERPE
E
T
XIS 40°N
20°N
South
North
STAR MOTION
ES
HE
ÖT
W
BO PY
M3
8 M4
Ecliptic
M AY N OR T H E R N L A T IT U DE S 57
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST x
M6
us
LE O
OR
S
MI N
UR SA M
A JO R
E AT
O
AN XT LE
SE
4
NC
7
ER
N
N LY
A
O
R T
X
g Re ul
R
5
Variable star
M8
1
CO R
VU S M104
M87
M64
Spica
M53
I
VI R G O
rus
Arctu
M3
COMA BERENICES
VENATIC
M51
Mizar
URS A MI N
BOÖTE
OR
N ORTH
NORTH
LOOK I N G
CA NE S
per
Big Dip
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
S
NA
P EN
M5
SE R
CORO
PU
T
LI S
CO
REA
A S C
BO
D RA
NGC 6543
M1
20°S
3
POINTS OF REFERENCE Horizons 0°
40°S
HE
LE
92
U RC
M
S
4
N
IC
O
0°
46
R
65
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES Date April 15 May 1 May 15 June 1 June 15
Zeniths
LA
UI
7
1 am
Midnight
11 pm
10 pm
9 pm
40°S
Ecliptic
Daylight-saving time
AQ
0 M1
CR
DR c
E ST
4
EAST
33
66
RA
LI B
HY Eclipti
H
W
3
a
SE CA RPE UD N S A
M5
CA 1
Ve g
2 M1
M1
S HU UC
HI OP
C
NG
A
LY R
ST
A
E
M4
0
STAR MAGNITUDES -1
2
MAY | SOUTHERN LATITUDES
lu Pol
58
4
TUM 22
M
M11
ILA
EAST 54
SA
G
IT M 55
M
IC RO
EA
S
SO
U ST
PI UM
US
SC OP
GR
S
LE IUM
AR A
A
TUC
PAV O
RM
S
CI R CIN
ri
ntau
α Ce
A NA
US
4
MUS C
Acrux
A
S OUT H
SOUTH
Achernar
H YD RU S
x
Gacru
C RU X
S
C H A MAE L E O N
Coalsack Nebula
β Centauri
Becrux
RU CENTAU
NGC 5139
LO OK I N G
P HO E N I X
NGC 10
SMC
OCTANS
APUS
T RI A N GULU M AU S T R AL E
PU
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
A
M
VE
LA
Horizons 0°
20°S
A
40°S
RA
TLI
DO
AN
POINTS OF REFERENCE
M O GI U H O RO L
U LU
ANS
NGC 2516
VO L
LMC
INA
A
R NGC 3114
DR
DO
Ca
pu
s
Zeniths
no
P PU
S
0°
PI
SO
U
TH
M48
M
CR AT E HY
R E TIC
ME NS
CAR
NGC 3532
Planetary nebula
MAY | SOUTHERN LATITUDES
6 M2
RO CO STR AU
TH
69
DU
7
IN
TE
la
CO
M
S
6
IU
M8
N AL A IS
NO
LU
M83
US
RV
S
XI PY
M
au
CO
Sh
BA LU M
M
US
T
5 M2
8
PI
TA R
An es tar
20°S
40°S
South
North
STAR MOTION
ES
8 M1
3
SCU M2
M2 M
M9
7
1
U
OR SC US CH
Ad ha ra
ON O
CER
OS 7
AQ U M1
M4
6 6
3 M2
HI
M4
M1
OP 62
R AJ O
M9 M
IS M
M2
9
CA N
M1
1
0 M8
Ecliptic
M4
M4
W
CO
M AY S OU T H E R N L A T IT U DE S 59
WEST
60
MO NT H LY S KY GUID ES: OVERVIEW S
JUNE It is summer in the Northern Hemisphere, and with lighter evenings the time for observation is reduced. For observers in the Southern Hemisphere, the dark skies offer a plethora of celestial sights to look for, including the constellations in the Milky Way.
HERCULES
NOON
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
5
Beta (β) Herculis, or Kornephoros, 2.8
Herculis
Her
June–August 5
16h 17h 18h Hercules’ waist is formed by DRACO 50º four stars that make the CYGNUS 42 asterism known to υ τ 52 astronomers as the ι φ “Keystone.” The stunning σ LYRA 30 globular star cluster M92 40º M13 lies one-third of Vega η ρ 69 the way south along M13 KEYθ π STONE an imaginary line 68 30º ζ between the stars 104 ν ε ξ Eta (η) Herculis and ο μ λ Zeta (ζ) Herculis. δ 100 M13 contains 113 NGC 6210 109 β 106 20º roughly 250,000 95 HERCULES 110 γ 102 stars and can be 111 CLUSTER 93 ABELL 2151 easily seen with a Rasalgethi ω α pair of binoculars. 60 29 10º A small telescope shows it very well. AQUILA
NORTHERN LATITUDES THE STARS Looking north Ursa Minor, the Little Bear, is clearly visible with Draco, the Dragon, wrapped around it. The tip of the bear’s tail is marked by the pole star, Polaris. If observing from a site with a clear southern horizon, you will be able to spot the constellation
Size ranking
Scorpius. Look out for the unmistakable bright star Alpha (α) Scorpii, Antares, shining with an orange-red tint. SIGHTS OF INTEREST If you have a small telescope, train it on M13, the finest globular cluster in the northern skies this month. It lies in Hercules, which is high in the sky at this time. Also look for another globular cluster M5, which
χ
BOÖTES
CORONA BOREALIS
κ
SERPENS CAPUT
OPHIUCHUS
sits in the head of the constellation Serpens, the Snake. These star clusters are roughly magnitude 6 and can be seen through binoculars. If you are an enthusiastic galaxy
9 AM
50°
40°
observer, use a telescope to reveal two well-known spiral galaxies, M51 and M101, sitting near the handle of the “Big Dipper.”
6 AM
30° 15
13
20°
12
15
Pleiades 19
ARIES 12
11
Aldebaran
MIDNIGHT
16
14 17
Hyades
10°
3 AM
11
11
PISCES Altair
Bellatrix
AQUARIUS
TAURUS
0° Mira Rigel –10°
18 URANUS
19
17
18
CAPRICORNUS
19
19
18
PISCES
17 16 15
14 13
Fomalhaut 18
17
16
15
SAGITTARIUS 14
13
12
12
11
11
AQUARIUS CETUS
M NEPTUNE
O
R N I N G
S K Y
Shaula
JUNE
61
SOUTHERN LATITUDES SIGHTS OF INTEREST There is no shortage of interesting objects to view from southern latitudes this month. A good place to start is the constellation Scorpius, which contains the stunning open clusters M6 and M7, both of which can be viewed with the naked eye. They sit not far from the Scorpion’s tail and a pair of binoculars shows them very clearly. There is also the open star cluster NGC 6231 nearby, lying close to the star Zeta (ζ) Scorpii. The magnificent globular cluster Omega (ω) Centauri in the constellation Centaurus is still on show. It is breathtaking when seen with a large telescope. Also in the south, not far away from Centaurus, in the constellation Crux, you can find the dark Coalsack Nebula. You can also view the spectacular Jewel Box Cluster and M83, a spiral galaxy in Hydra.
THE STARS June is a wonderful time for night-sky observers in the Southern Hemisphere. The rich star fields of the Milky Way galaxy stretch right across the sky from the southwest to the northeast. Scattered among them are the sparkling constellations Centaurus, the Centaur; Crux, the Southern Cross; as well as Scorpius, the Scorpion; Carina, the Keel; and Sagittarius, the Archer. High in the south you will see the constellation Lupus, while the distinctive shape of Scorpius will help you get your bearings. Its brightest star is the orange-red Antares. Be sure to scan your eyes across the beautiful star fields in the constellation Sagittarius, especially if you are observing from a dark sky site. Looking north the constellations Boötes, Hercules, and Ophiuchus are visible.
S C O RP I U S Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
33
Alpha (α) Scorpii, or Antares, 1.0
Scorpii
Sco
June–July
You cannot fail to spot the constellation Scorpius, which has one of the most recognizable patterns in the night sky. It is home to many excellent targets for an amateur telescope. However, to see the entire constellation in the night sky your location should be to the south of latitude 40 degrees north. Scorpius’ brightest star is the orange-red Antares, Alpha (α) Scorpii. It is a supergiant star with a diameter about 800 times that of our own star, the Sun.
ψ
–10º
ξ
Sco X-1
SERPENS CAUDA
–20
ν β
OPHIUCHUS Ecliptic
ο 22
SAGITTARIUS
Antares
τ
M6
RR
Shaula
κ λ –40º
ι
ε
NGC 6383
M7
2
δ 2
π
M4
1
LIBRA
ρ
13
SCORPIUS
LUPUS
μ2 μ1
υ
NGC 6124
NGC 6322
θ
α
M80
σ
η ζ
NGC 6231 NGC 6178
NGC 6388
NORMA TELESCOPIUM –50º
ARA 18h
17h
16h
NOON 3 PM
Sparkling Scorpius The distinctive constellation Scorpius is rich in deep-sky objects to observe, including the marvelous open clusters M6 and M7, found near its tail (top left).
50° 6 PM
40°
Castor
GEMINI
Pollux
15
MIDNIGHT
19
18
19 14
13 13
17
13 20°
LEO
Arcturus
15
CANCER Regulus 12
Betelgeuse
16
VIRGO
10°
Procyon
11
OPHIUCHUS
30° 16
9 PM
0°
17 12 14
–10°
13 Spica
14 15 16
16
18
LIBRA
19
POSITIONS OF THE PLANETS
Antares
This chart shows the positions of the planets in June from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
SCORPIUS
N G N I E E V
S
K
Y
except Mercury, the dot indicates the planet’s position on June 15. Mercury is shown only when it is at greatest elongation (see p.125). For the specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
Mars’s position on June 15, 2011
11
Saturn’s position on June 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
62
MONT HLY SKY GUID ES: HIGHLIGHTS
JUNE NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH One of the finest double stars of the northern skies is on show in the east at this time of the year. Albireo, or Beta (β) Cygni, in Cygnus is a must-see for any beginner due to the ease with which the stars can be separated. It can be seen through a small telescope, with one of its stars shining gold and the other with a blue hue. The open cluster M39, also in Cygnus, is another good small-telescope target, as is the variable star Delta (δ) Cephei that varies between magnitude 3.5 and 4.4 every 5 days and 9 hours.
Date
Standard time
Daylight-saving time
15 May
Midnight
1 am
1 June
11 pm
Midnight
15 June
10 pm
11 pm
1 July
9 pm
10 pm
15 July
8 pm
9 pm
Zenith 20°N
HERCULES
Arcturus BOÖTES
40ºN
60ºN
Vega DRACO
Albireo Big Dipper
URSA MINOR
URSA MAJOR
CYGNUS
Deneb
LEO
Polaris
CEPHEUS
δ Horizon 20ºN
Regulus li Ec ic pt
CASSIOPEIA AURIGA
CANCER
Albireo A small telescope shows the striking colour difference of the two stars, set against the star fields of the Milky Way in Cygnus. The magnitude 3.1 and 5.1 stars lie 380 light-years away from Earth.
ANDROMEDA
PERSEUS
Castor
Capella
Horizon 40ºN
Pollux
W
ES
PEGASUS
EA
GEMINI
T
ST
Horizon 60ºN
LOOKING SOUTH The constellation Boötes, the Herdsman, is high in the sky in June. Its brightest star Arcturus, with a magnitude -0.04, is a red giant star that is an incredible 25 times larger than our Sun. Also still on view, to the east of Boötes, is the globular cluster M13 in Hercules. Low down on the horizon is Scorpius, which contains some interesting objects, such as two open clusters, M6 and M7, and a globular cluster M4. Both M6 and M7 are visible to the naked eye and their individual stars can be seen through binoculars.
Zenith 60°N
DRACO
URSA MAJOR
40ºN
Vega
BOÖTES HERCULES 20ºN
Arcturus
SERPENS CAPUT
OPHIUCHUS SERPENS CAUDA
Altair
VIRGO LEO LIBRA
Antares
AQUILA
Spica Regulus
SAGITTARIUS Horizo n Ec
M6 in Scorpius A magnitude 4.2 open cluster, M6 can be found sitting not far from the “sting” in the tail of Scorpius, just north of M7. It is also known as the Butterfly Cluster.
t ic lip
SCORPIUS
60ºN
LUPUS Horizon 40ºN
EA
ST
CAPRICORNUS ARA
CENTAURUS
α Centauri β Centauri CRUX
HYDRA
N n 20º Horizo
W
ES
T
JUNE
JUNE SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH While there may be more impressive sights in the southern part of the June sky, there is also much to see when looking north, such as the globular clusters M13 and M92 in the constellation Hercules. There are also plenty of interesting clusters to look at in Ophiuchus. Besides the two globular clusters M10 and M12, and the open cluster NGC 6633, be sure to look out for the magnitude 4.2 open cluster IC 4665. It is composed of a group of 30 stars and is a lovely sight through binoculars.
Zenith 40°S
LUPUS SCORPIUS
Antares
20ºS
ipt Ecl
HYDRA
SAGITTARIUS
LIBRA
ic
OPHIUCHUS
0º
Spica
SERPENS CAUDA
SERPENS CAPUT
VIRGO
Arcturus HERCULES AQUILA BOÖTES
Altair
Vega LEO
ºS
Horizon 20ºS
Big Dipper
ES
on 4 0
DRACO
Regulus
W
Horiz
CYGNUS
URSA MAJOR
T
Deneb URSA MINOR
º on 0 Horiz
EA
ST
CEPHEUS
M13 in Hercules The globular cluster M13 in Hercules is a spectacular sight in a large-aperture telescope. A large Dobsonian telescope, for example, will show it as a ball of thousands of stars.
LOOKING SOUTH If you are looking south in the southern hemisphere, you will be met with a rich variety of objects visible with just the naked eye, or with binoculars or a small telescope. M22 in the constellation Sagittarius is an impressive magnitude 5.1 globular cluster, while the emission nebula, M8, is a fine target for binoculars. Meanwhile, Omega (ω) Centauri, arguably the finest globular cluster in the night sky, sits at the heart of Centaurus, the Centaur.
Zenith 0°
LIBRA OPHIUCHUS
20ºS
VIRGO
Antares SERPENS CAUDA
SCORPIUS
tic lip Ec
Spica 40ºS
ARA
LUPUS
α Centauri SAGITTARIUS
HYDRA
β Centauri
AQUILA
CRUX
CENTAURUS
PAVO OCTANS CAPRICORNUS CARINA
VELA
Horiz on 0 º
TUCANA GRUS
EA
Horizon 20ºS
Fomalhaut
ST
PICTOR PHOENIX
Achernar
PUPPIS
Canopus ERIDANUS
ºS on 40 Horiz
WE
ST
M8 in Sagittarius Also called the Lagoon Nebula, M8 can be seen through binoculars as a glowing patch. The view through a large telescope is mesmerizing, with several stars nestled in and around the nebula.
63
MO NT H LY S KY GUID ES: SKY GUID ES
WEST CA
l Regu
H
W
E
us
X
UR SA
6
MA J OR
IGA
Big
I
A
Dip r
pe
Cape lla
M8 1
M51
UR
LEO l Po
GE
lu
M
IN
x
I
N O
R 8
TI C NA
OR
LY N
M 37 M3 M3
VE
IN
4
T
M
01
BO
M1
ÖT E
S
DRACO
Polaris
CAMELOPARDALIS
P E RS E US
NGC 869 NGC 884
M34
N ORTH
NORTH
r
LOOK I N G
iza
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
EU S
2
U LU
M5
NG
IA
Vega
M
M
1
39
M3
CE LA
DR
A RT
AN
O
N
O
R
TH
40°N
Midnight
11 pm
10 pm
9 pm
8 pm
60°N
US
S
Standard time
OBSERVATION TIMES Date May 15 June 1 June 15 July 1
Zeniths
July 15
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
TR I A
OPE
C EP H
C A SS I
M103
Planetary nebula
5
1 am
Midnight
11 pm
10 pm
9 pm
20°N
Ecliptic
Daylight-saving time
M1
LA E CU
H IN U
DEL P
A
ES
M
M4
2
US
2 M9
ES UL
RC HE
CAN
Ca
ST
st or
O
ER 1
EAST
LE
NC 0
STAR MAGNITUDES -1
ne
LP
VU
Albireo 29
b
M
De
M57
CY GN
A
LY R
ULE
EQU
S
SU
GA
PE
ST
A
E
M27
ED
M
URS A M I N OR
JUNE | NORTHERN LATITUDES
M67
64
AQ UIL
A
ST
11 54
M 26
C
R ICO AP R
NU M
S 55
SA
G
AR IT T
A
IU
69
CO U S RO TR N A AL IS
M
M
U
S
EA
ir M
M 22
UT
SO
U
28
TE
M
L ES
7
1
CO P
M
M8
M2
M 6
M 14
I UM
23
A
M
UD
16
M 1 M 7 18 M 24
M
CA
AR A
ula
Sha
M9
OP
9
0
M12
res M4
S ER P E
LO OK I N G
α Centauri
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
us ri
3
S
VU
Horizons 60°N 40°N 20°N
G
M
87
4 10
M
R CO
ux acr
GO
5139
RU
rux Bec
TAU CEN
BE
VI R
NGC
M8
ca Spi
M
64
CO R E MA N IC ES
POINTS OF REFERENCE
ntau β Ce
tic Eclip
S OUT H
SOUTH
CI RC I N US
LUPUS
LI BR A
M5
N S C A PU T
TR IANGULUM A US TR A LE
N O R MA
PIUS
M80
SCOR
Anta
M1
HU S
M1
UC
M62
HI
B
3 M
ur
S TE OÖ
53 M
Ar ct
JUNE | NORTHERN LATITUDES
EAST SC 25
S
EN
TH
Alta
RP M
SE M
A Zeniths
S
O
HY
C
TE RA
LE 60°N
SO
U
R
TH
A
A ITT S
DR
S AG
T 40°N
STAR MOTION
20°N
South
North
Ecliptic
S XT AN
P VUL
L ECU LE
SE
HE U RC
ES
M13
W
CORONA BOREALIS
J UN E N OR T H E R N L A T IT U DE S 65
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
T
M
LE 87
M6 4
GO
VI ru s
Ar ctu
M3
1
r
Miza
S
M5
S CAP UT
D R A CO
CORO N A B O RE A L IS
PE N
ÖTE
S ER
BO
M101
RA
MI NO M5
ES
R
NI C
M53
BE RE
ca
L EO
I
CO MA AT IC
4
VE N
R
Spi
O M
NE S
SA
CA
UR AJ O
Big D ipp er
LIB
u Reg lus
R
N O
R T 2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
H
CU
OP
HE R
M13
Planetary nebula
2
LE S
M9
IC 4
M16
a Veg
665
NGC
A
663
40°S
LYR
20°S
UM
57
VU
Date
EC
U
G CY
LP
May 15 June 1 June 15 July 1 July 15
Zeniths
O
o re bi Al
N
0°
R
S
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
M
3
M26
SE R CA P EN UD S A
POINTS OF REFERENCE Horizons 0°
M11
SCUT
M10
S 1
4 M1
TAN
ES
ic
Eclipt
H
W
UR S A M IN O R
N ORTH
NORTH
LOOK I N G
0 M1
JUNE | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
S
LE U
UU
US
HIN
LP
DE
ST
EQ
air
TA
Alt
AG
IT
27 M
b
29 M
De
ne
A
E
LA
UI
AQ LA
US N
US CH
IU
12 M
S EX
66
CA
PR M
O IC
RN
M
C PI S
EAST
IS
30
AU
R ST
IN
OE NI X
TE TU
C AN
U
US
U SC
ma Fo
ut
lha
SO
A
IC
U ERI DA N
US
NGC 104
PAVO
Ache rnar
A
la
AR
au
ST
R TA PH
S
R CO ST U A
DU
M
M6
IU
Sh
P IU S A
M
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
C5
M83
DO
NS
PIC
Horizons 0°
20°S
RI N
A
40°S
s pu no Ca
TO R
CA
POINTS OF REFERENCE
D OR A
VO L A
A
x Acru
G
x acru
US
139
MUS C
C RU X
LMC
S OUT H
R E T I C U LU
ME N S A
C H AMA EL E O N
NG
AU R CEN T β Centauri Becrux
CIRC I N US
SOUTH
LO OK I N G
S
α Centauri
AP U S
H Y D RUS H O RO L O G I U M
SMC
OCTANS
TRIANGULUM AU S T R A L E
NO R M
SC OR
LU P U
VE
A LA
Zeniths
VUS CO R
0°
LI
CRA TER
T AN
SO
U
TH
TAN S XI S
20°S
40°S
South
North
STAR MOTION
SEX
A BR
JUNE | SOUTHERN LATITUDES
EA
IN
SC OP
62
TH
T GI
TO R
55
M
LE
M7
LP
M
IU
SA
SC OP
M 54
RO
2 9
S
M6
S
M2 8
IU
M2
O RA NA LI S
M8
DR
M9
HY
M25
A
M17
S
M23 M21 M18 M24 M
PI
M19
PU P
t
T
An
ES
M4 res a
W
M80
PY
LI
Ecliptic
J UN E S OU T H E R N L A T IT U DE S 67
WEST
68
MO NT H LY S KY GUID ES: OVERVIEW S
JULY The northern night skies will continue to entice stargazers through the summer. High in the sky is Hercules, home to the magnificent M13. In the southern latitudes, the spectacular constellations Scorpius and Sagittarius are visible.
LYRA
you can find the Summer Triangle asterism, while the constellation Ophiuchus sits in the south. Look for Boötes in the west, with the bright star Arcturus at its base. Below is Virgo and its brightest star Spica. This is also an ideal time to observe the rich region of the sky covered by Scorpius and Sagittarius.
NOON
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
52
Alpha (α) Lyrae, or Vega, 0.0
Lyrae
Lyr
July–August 18h
19h
You can easily find the relatively small constellation Lyra, the Lyre, by locating its brightest star Alpha (a) Lyrae, or Vega. Vega is one of the three stars of the famous Summer Triangle asterism. The planetary nebula M57, or the Ring Nebula, is also in Lyra and is a much-loved target for amateurs. Larger aperture telescopes will show the nebula as a small smoky, gray ring.
NORTHERN LATITUDES THE STARS The constellation Hercules is high in the sky this month and it is a good time to observe its celestial treasures, such as the globular cluster M13. Below M13 lies the winding constellation Draco, the Dragon. Toward the east
Size ranking
CYGNUS LYRA
R RR
ε
1,2
40º
η
δ1,2
θ γ λ
30º
α
Vega
κ
ζ1
β M57
M56
HERCULES VULPECULA
interesting globular clusters, such as M10 and M12. These clusters are visible with binoculars, while a telescope will resolve many of their individual stars. If you have a pair of binoculars, look for the open clusters IC 4665 and NGC 6633, also in Ophiuchus.
SIGHTS OF INTEREST The globular cluster M13 in Hercules is a must-see object this month, as is another globular cluster, M5, which can be found in the nearby constellation Serpens. Ophiuchus also has some
9 AM
URANUS 6 AM
50°
19 18
PISCES
17 16
Capella
15 14
40°
13 12 11
Castor
GEMINI
30°
3 AM
TAURUS
15 13
11 19
20°
13 14
14
11 17 12 Aldebaran
13
12
CETUS
Pleiades
MIDNIGHT
ARIES
Hyades
11
PISCES
10°
Altair
Betelgeuse Bellatrix 0° Mira Rigel
AQUARIUS
–10°
18 Fomalhaut 19
18
17
16
15
14
13
12
SAGITTARIUS
11
M Noctilucent clouds Look out for these ethereal high-altitude clouds after sunset and before sunrise in June and July. They can take on many beautiful forms.
AQUARIUS
CAPRICORNUS
O
NEPTUNE
R
N
I N
G S
K
Y
JULY
69
SOUTHERN LATITUDES SIGHTS OF INTEREST At this time of the year, the constellation Sagittarius offers some exceptional deep-sky objects. The striking globular cluster M22 is visible to the naked eye if you have good observing conditions. The Lagoon Nebula, or M8, lying above the spout of the “Teapot”, is a glowing cloud of gas and a stunning sight through binoculars. It appears as a misty patch with the star cluster NGC 6530 nestled within it. Other famous deep-sky objects in Sagittarius are visible through a telescope, including the Trifid Nebula, or M20. However, you can see one particularly bright patch of the Milky Way—M24—with just the naked eye. Beside Sagittarius, Scorpius contains the bright open clusters M6 and M7, which remain high in the sky this month. To the north in the constellation Serpens Cauda, the Tail of the Serpent, lies the open cluster M16 in the much fainter Eagle Nebula.
THE STARS Sitting high in the southern skies, Scorpius is easy to spot this month. Nearby are the constellations Sagittarius and the slightly less prominent Libra. Sagittarius is famous for the “Teapot” asterism formed by some of its brightest stars, and at this time it sits very high in the sky. When you look toward Sagittarius and Scorpius, you are peering toward the center of the Milky Way galaxy. This whole region is full of rich and beautiful star fields, which are a joy to explore using binoculars. A little lower in the sky are the bright stars Alpha (α) and Beta (β) Centauri, also known as Rigil Kentaurus and Hadar respectively. Very close to them you will spot the smallest constellation in the night sky—Crux, or the Southern Cross.
S A G I TT A RI U S Size ranking
Brightest star
Genitive
15
Epsilon (ε) Sagittarii, 1.8
Sagittarii
Abbreviation
Highest in sky at 10 pm
Sgr
July–August
20h
19h
AQUARIUS
The constellation Sagittarius, the Archer, is nestled within a mesmerizingly detailed part of the Milky Way. You can find it by first locating the “Teapot” asterism, which forms the constellation’s hub, close to a notably bright swathe of the Milky Way. A scan of Sagittarius with binoculars or a small telescope will reveal many rich star clusters and bright nebulae, such as the beautiful Lagoon Nebula.
18h
OPHIUCHUS
CAPRICORNUS NGC 6818
56 –20º
60
π ο ψ
52
ω
ξ1,21,2 ν
M55
SAGITTARIUS
λ
M22
M21
11
M20
M28
4 M8
φ
X M69
M70
θ1
M23
μ
TEAPOT
MILK DIPPER M54
–30º
M24
21
Nunki
τ ζ σ
59 RR
62
M17 M18 M25 Y
NGC 6716
43
ECLIPTIC
M75
SERPENS CAUDA
SCUTUM
υ ρ1
NGC 6822
ε
NGC 6723
W
γ
δ
Sgr A*
Kaus Australis
η
SCORPIUS Shaula
α
ι
–40º
CORONA AUSTRALIS
β1 β
2
TELESCOPIUM
INDUS
ARA NORMA
–50º
METEOR SHOWER When observing in late July, look out for the Delta Aquarid meteor shower, which peaks on July 29. If observing from a dark sky site you should be able to spot around 20 meteors every hour.
The galactic hub If you look toward the constellations Sagittarius and Scorpius on a clear night in the Southern Hemisphere, then you are looking in the direction of the very heart of our galaxy.
NOON
50°
3 PM
40°
6 PM
Pollux
30°
17 16 14
Arcturus
MIDNIGHT
9 PM
19
LEO Regulus 18 17
15 15
13
20°
12
18
11 10°
CANCER
16 Procyon 0° 11
VIRGO
OPHIUCHUS
12
17 –10°
14
13 14
12
Spica
18
15 19
18
17
16
16
19
LIBRA
POSITIONS OF THE PLANETS
Antares
SCORPIUS Shaula
This chart shows the positions of the planets in July from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
except Mercury, the dot indicates the planet’s position on July 15. Mercury is shown only when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
E V E N I N G
Y S K
Mars’s position on July 15, 2011
11
Saturn’s position on July 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
70
MONT HLY SKY GUID ES: HIGHLIGHTS
JULY NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH Ursa Major, the Great Bear, is home to several galaxies that can be seen with amateur equipment. M81, or Bode’s Galaxy, appears as a fuzzy, gray blob through binoculars or a small telescope. The double star Alcor and Mizar is also worth a look while enjoying the sights of Ursa Major. In the east Cygnus, the Swan, looks magnificent at this time of the year. The more adventurous deep-sky observers should try to hunt down NGC 7000, the North America Nebula, just southeast of the star Deneb.
Date
Standard time
Daylight-saving time
June 15
Midnight
1 am
July 1
11 pm
Midnight
July 15
10 pm
11 pm
August 1
9 pm
10 pm
August 15
8 pm
9 pm
Zenith 20°N
HERCULES
40ºN
Vega BOÖTES
CYGNUS 60ºN
Arcturus
Deneb
DRACO
Mizar
CEPHEUS
Alcor URSA MINOR
URSA MAJOR
Polaris
Big Dipper
CASSIOPEIA ANDROMEDA
Horizon 20ºN
PEGASUS
PERSEUS LEO
Alcor and Mizar The double star system of Alcor and Mizar is visible to the naked eye. You can find it in the handle of the famous Big Dipper (Plough) asterism in the constellation Ursa Major.
W
Horizon 40ºN
Capella
ES
PISCES
T
GEMINI
AURIGA
Castor
Pollux
EA
ST
Horizon 60ºN
LOOKING SOUTH One prominent marker of the night sky in the northern summer is the asterism known as the Summer Triangle. The corners of this large isosceles triangle are formed by the three bright stars Altair, Vega, and Deneb. Another interesting sight is the multiple star system, the “Double-Double” (see p.86) or Epsilon (ε) Lyrae, in Lyra. Viewing it with binoculars shows a pair of stars, but, closer inspection with a telescope reveals that each of these stars is a pair of stars itself.
Zenith 60°N
DRACO
Epsilon (ε) Lyrae
Deneb
40ºN
Vega
HERCULES
CYGNUS
BOÖTES
20ºN
SERPENS CAPUT
AQUILA
Altair
Arcturus
OPHIUCHUS
SERPENS CAUDA
PEGASUS
LIBRA
Antares
c Eclipti
AQUARIUS
Horizon
VIRGO 60ºN
Spica
SAGITTARIUS CAPRICORNUS
The Summer Triangle This asterism is a useful navigational aid when finding your way around the summer night sky. Look for dark lanes in the Milky Way that cut across the triangle through Cygnus and beyond.
SCORPIUS
Horizon 40ºN
ARA
EA
ST
Horiz
on 2 0 ºN
CENTAURUS LUPUS
HYDRA
W GRUS
PAVO
α
ES
T
JULY
JULY SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The wonderful globular cluster M5 is high in the sky at this time. It is roughly 25,000 light-years away from Earth, toward the constellation Serpens Caput. A small telescope brings many of its outer stars into focus. A short hop east over Ophiuchus into Serpens Cauda you will find the open cluster M16 surrounded by the much fainter Eagle Nebula. This cluster can be observed with a pair of binoculars. Also look out for Alpha (α) Librae, a double star in the constellation Libra, the Scales.
Zenith 40°S
SCORPIUS
SAGITTARIUS
Antares
20ºS
LIBRA
Ecl ipt ic
SERPENS CAUDA 0º
OPHIUCHUS
Zubenelgenubi
CAPRICORNUS AQUILA
SERPENS CAPUT
Altair
Spica HERCULES
AQUARIUS
Arcturus Vega
BOÖTES
CYGNUS
VIRGO izon Hor
40ºS
Deneb DRACO PEGASUS
Horizon 20ºS
W
ES
T
Ho r i zon
URSA MAJOR
0º
EA
ST
CEPHEUS
URSA MINOR
Alpha (α) Librae The second brightest star in Libra is called Zubenelgenubi (Arabic for “the Southern claw”). It is a binary star system, and a pair of binoculars easily shows its two stars.
LOOKING SOUTH The “Teapot” asterism, made of eight stars, lies among the stars of the Milky Way in the constellation Sagittarius. Its stubby spout is marked by the stars Gamma (γ), Epsilon (ε), and Delta (δ) Sagittarii, while Phi (ϕ), Sigma (σ), Zeta (ζ), and Tau (τ) make its handle. Scattered around the Teapot are some interesting binocular and small-telescope targets, including the bright Lagoon Nebula M8, the magnitude 4.6 open cluster M25, and the globular cluster M22.
Zenith 0°
OPHIUCHUS
SERPENS CAUDA 20ºS
AQUILA
tic lip Ec
φ σ ε τ ζ
δ γ
Antares SCORPIUS 40ºS
LIBRA
SAGITTARIUS
LUPUS
ARA
VIRGO
CAPRICORNUS
α Centauri
PAVO
AQUARIUS
Spica
β Centauri
GRUS
HYDRA
CRUX
OCTANS
CENTAURUS
TUCANA
Fomalhaut
Horizon 0º
PHOENIX
Achernar
EA
ST
CARINA
PICTOR ERIDANUS
Canopus
Horizon 20ºS VELA
ºS n 40 Horizo
WE
ST
M22 in Sagittarius A small telescope shows many of M22’s brightest stars. It is the third-brightest globular cluster in the sky and can be seen with just the naked eye in particularly dark and clear skies.
71
MO NT H LY S KY GUID ES: SKY GUID ES
WEST O
7
LE
A N N AT ES IC I
64
C
U
RS A
M3
M AJO R
M5 1
S
E ÖT
MI NI
R tor
GE Cas
BO
OR
A COM ICES EN
O
T
VE
2
3
4
5
Variable star
LYN X
Miza r
M101
M81
Globular cluster
DEEP-SKY OBJECTS Galaxy
O
SA
D RAC
UR
M 92
H E RC U L E S
M IN O R
Polaris
AURIGA M38
Diffuse nebula
R LY
A
Planetary nebula
CY
G
PH
EU
S
NG
C
70
00
M
A
52
C8
3
S
69
SEU
NG
M10
P EI
884
SIO
NGC
PE R
L
4
AN
M3
DR
OM
ED
M
A
31
TR
IA
NG
AR
U
O
IE
N
R
Midnight
Standard time
11 pm
Midnight
1 am
Daylight-saving time
TH
11 pm
10 pm
Ecliptic
10 pm
20°N
9 pm
40°N
9 pm
60°N
8 pm
OBSERVATION TIMES Date June 15 July 1 July 15 August 1
Zeniths
August 15
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
S
CAS
DALI
CE
CAMELOPAR
Capella
N ORTH
NORTH
LOOK I N G
Open cluster
EAST
De
M
N 1
ES
P ISC
TA
ER AC
9 M2
b ne 9 M3
S
NU
S
P E G A SU M
BE R M
IN
H
W
ES T
r
M8
0
STAR MAGNITUDES -1
M
LU
33
ST
A
E
S
Big Dippe
JULY | NORTHERN LATITUDES
LE O
72
S 2
U AQ
I AR US 30
IS S SC U P I RI N ST AU
SO
U ST
M
IN DU
S
M55
ITTA
1
M54
M22
M69
M25
SCUM26 T UM
M1
A
M28
M17 M18 M24
M16
CU
S
M19
M62
M12
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
N RO L CO REA BO
A
SE R
IS P
ES CA
S
us
Horizons 60°N 40°N 20°N
PU
RA
LU
L IB
M5
ur Ar ct
ÖT
BO S EN
T POINTS OF REFERENCE
MA
M4
N OR
M80
res
Anta
HUS
M10
LE
O P H I UC
R HE
S OUT H
SOUTH
Shaula
M6
M9
LO OK I N G
PAVO
M7
M21
M14
A RA
M23 M8
SE R P C AU E N S DA
COR AU S O N A TRAL IS T EL ES C O P IUM
RIUS
A
UL
13
JULY | NORTHERN LATITUDES
EAST M
EA
M
H
EU IU
S S AG
A
SC OP
r
RO
S
tai
IC
NU
ptic
IL
T QU
EC
LP
T
M
EQ L UU IC OR
L NU
PR
DE
I PH Ecli
Al
CA
M15
S
TA
GI PU
SA N
US
Zeniths
CE
UR TA
C BE OMA M53 R E NI CE S
D HY
60°N
SO
U
83
G
U AS 27
M
M
TH
RA
O RG
PE
VU
VI
S NU ica
eo bir
Sp
Al
T
G 57
40°N
20°N
South
North
STAR MOTION
ES
M
A
W
CY R LY 4 M10
a
US
g Ve
CO RV
M
Ecliptic
J UL Y N OR T H E R N L A T IT U DE S 73
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST M
M 53
A
SE
M5
RP E
O
NS
CO R
CA
NA
PU T
B OR EA L IS
M
M13
12
O
PH I
NI CE M92
H E RC U
M14
L ES
UCHU S
9
01
rct uru s
M1
MI NOR
M2
3
16
17
M
M
EN S S E RP A D C AU
LYRA
Vega
26
S
N
VE
S I NE T I C CA N A
O
R T 3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
M
11
Planetary nebula
VU
M57
A
LA
UL
UI
EC
AQ
LP
S
o ire Alb
NU
EUS
C YG
C EP H
Al
r i ta
9
DE
HI
M
52
Date
LA
June 15 July 1 July 15 August 1
CE
August 15
Zeniths
A RT
N
O
0°
R
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
9
LP
M3
40°S
b ne De
A TT 27
GI SA M
M2
20°S
POINTS OF REFERENCE Horizons 0°
M2
S
R IU
5 M2
N ORTH
NORTH
LOOK I N G
UR SA
M
B
M 3
M 51
O Ö TE S
GO
RE M R
10
64
A
AJ O
r
Mi za
DRA CO
M
BE
UR S
T
RA
A
H
W
ES
LIB
M CO 2
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
VIR
7
1
S
SU
UA
AQ
ED A
S
LEU
UM
UT
SC
M
M M2 18 4
JULY | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
PE
GA
DR OM
AN
ST
A
E
5 M1
UU
EQ S
NU
M8
74
A
A QU S CI US P IS R IN ST AU
RI al ha
m Fo
SC
EAST
P UL
TO
R
SO
U
X
ER ID AN
OP
IU M
US
Ach ern ar
SC
US
RO L
NGC
A NA
HO
TUC
IN D
RE TI
M
SMC
OG I U
104
US
9 M1
s anopu C
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
A
Planetary nebula
βC
i aur
Horizons 0°
C5
139
C RU
20°S
40°S
X
x cru Ga
NG
POINTS OF REFERENCE
I NA
ux Acr
rux Bec
ent
US
CAR
CA
NUS
MUS
P LU
ri ntau
α Ce
EO N NS VO L A
P I CTO R
C H AM A E L
AP U S
RM
CIR C I
NO
OR SC
0 M8
CE
83
LA
RU
S
Zeniths
VE
AU NT
O RG 0°
VI
SO
U
TH
4 M10
A
A
BR
LI
62 M
S OUT H
SOUTH
D OR AD O
LMC
An
UM GUL TR I AN ALE R AU S T
ARA
Shaula
MEN SA
OCTANS
M6
LO OK I N G
CULUM
S
PAVO
ESCO
HYD RU
TEL
M7
PI U M
C AU O R O S T NA RA L IS
tar es
US PI
S
VU
M4
JULY | SOUTHERN LATITUDES
US
ST
ut
EA
NI
0
OE
RO
TA
H
M3
S
US
NU
IC
IT
T
PH
GR
OR RIC M
RI
55
M
G SA CO R
M 54
R 20°S
40°S
South
North
STAR MOTION
E
M
W
CAP 9
DR
M6
HY
2
IA
M2 8
TL
M2
AN
M8
CR AT E
M21
ST
Ecliptic
Ecliptic
J U L Y S OU T H E R N L A T IT U DE S 75
WEST
Spica
76
MO NT H LY S KY GUID ES: OVERVIEW S
AUGUST
CYGNUS
On a warm August evening the most prominent feature from northern latitudes is the large Summer Triangle asterism. From the Southern Hemisphere, the magnificent center of the Milky Way is still sitting high in the sky. NORTHERN LATITUDES THE STARS Directly overhead is the bright star Vega in Lyra, as well as Deneb, which marks the tail of the constellation Cygnus. The shape of Cygnus means it is often called the Northern Cross. In the south, the rich regions around Scutum, Scorpius, and Sagittarius are sinking away.
SIGHTS OF INTEREST When observing Cygnus, look out for the Cygnus Rift. This dark lane of dust sits in front of the background stars and appears to split the Milky Way into two. Also look out for the Wild Duck Cluster, M11, in Scutum. It is clearly visible through binoculars.
Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
16
Alpha (α) Cygni, or Deneb 1.3
Cygni
Cyg
August–September 19h
22h
The constellation Cygnus, the Swan, is easy to recognize due to its large “cross” shape. Its brightest star Deneb, has magnitude 1.3, and marks the swan’s tail. The swan’s head is marked by the gorgeous double star Albireo, Beta (β) Cygni. A small 40º telescope reveals the two stars—one gold, the other tinted blue. Binoculars are perfect for exploring Cygnus’s beautiful star fields and clusters.
60
20h
21h
˚
60º
CEPHEUS 33
LACERTA 50º
63
M39
55
ρ
ξ
57
NGC 7000
72
σ υ
30º
μ1
α ο1
30
γ
ν
Cyg A
LYRA
22
M29
λ ε
29 28
47
52
Vega
15
P
Cyg X-1
39
NGC 6992
ζ
δ
Deneb
61
τ
θ
ο2
ω1
59
ι
NGC 6826
CYGNUS
π2 W
κ
ψ
π1
η
8 17
χ
φ
41
β2
Albireo
VULPECULA
METEOR SHOWER One of the finest meteor showers of the year, the Perseids peak around August 12. This is a great
9 AM 6 AM NOON
opportunity to lie back, take in the night sky, and hopefully see some meteors too—you should be able to spot one every minute or so. The meteors appear to come from the northern parts of Perseus. They are typically quite bright and are best seen after midnight.
Capella NEPTUNE
3 AM
50°
19
16
11 15
TAURUS 13
14
14 18
15
14
13
12
GEMINI
Pollux 15
20°
17
Castor
40°
30°
18
13 17
19
Pleiades
AQUARIUS
11 12
12
Aldebaran Hyades
12
17
11
11
PISCES CANCER
Betelgeuse Procyon
Bellatrix
AQUARIUS
0° Mira –10°
Rigel
19 18
Fomalhaut
PISCES
17 16 15
M
14 13 12 11
Perseid meteors The warm nights in August are a great time to sit back and watch the Perseid meteor shower unfold in the night sky above you.
O
R
N
I N
G
S
CETUS URANUS
K
Y
AUGUST
SOUTHERN LATITUDES
SCUTUM
Austrinus. Between Fomalhaut and the stars of Scorpius are the stars of the constellations Grus, Tucana, Pavo, and Ara. With clear skies you should have little trouble seeing the Small Magellanic Cloud sitting to the west of the star Achernar in Eridanus.
THE STARS When observing from southern latitudes you can find Sagittarius, the Archer, lying almost overhead; to its southwest lies Scorpius, the Scorpion. Low on the southwest the bright stars Alpha (α) and Beta (β) Centauri, also known as Rigil Kentaurus and Hadar, are sinking below the horizon, taking Centaurus with them. Low on the horizon between the stars of Centaurus and Scorpius is the constellation Lupus, the Wolf. In the east the bright star Fomalhaut lies in the constellation Piscis
77
SIGHTS OF INTEREST With the rich regions of Sagittarius and Scutum visible high in the sky, you can take your pick from a superb selection of binocular and telescope targets this month. To experience a real space-walking feel, pick up
Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
84
Alpha (α) Scuti, 3.8
Scuti
Sct
July–August
19h
The constellation Scutum, the Shield, is relatively small—the fifth smallest of 88 constellations. It is located between the stars of Aquila and Sagittarius, close to the constellation Serpens Cauda, the Snake’s Tail, in a wonderfully rich and interesting part of the Milky Way. The Polish astronomer Johannes Hevelius originally named it “Sobieski's Shield” in 1684, in honor of John Sobieski, the king of Poland at that time.
a pair of binoculars and “wander” along the Milky Way, from Scutum to Centaurus. If you have a telescope, the Lagoon Nebula makes a wonderful target in Sagittarius, and with a wide enough field of view you can also glimpse the Trifid Nebula, M20. Two interesting open clusters M6 and M7 are nestled among rich star fields in Scorpius, and both are
18h
OPHIUCHUS
AQUILA
ηβ R M11
ε
–10º
δ
α ζ
M26
SCUTUM
–20º
γ
SERPENS CAUDA
SAGITTARIUS
visible to the naked eye. The star field M24 in Sagittarius makes a great binocular target. Looking northward, you will find the planetary nebula M57, or the Ring Nebula. It is an interesting target for a small telescope, as is the larger planetary nebula M27, or the Dumbbell Nebula, in the constellation Vulpecula, the Fox. NOON
The Lagoon Nebula in Sagittarius M8, or the Lagoon Nebula (bottom right), can be seen with just the naked eye and makes an excellent target for a small telescope. It appears nestled among the rich star fields of our galaxy, the Milky Way.
40°
3 PM
30° MIDNIGHT 6 PM
20°
9 PM
LEO
Arcturus
19 19 15
16
Altair 13
Regulus
10°
16 16 0°
OPHIUCHUS
11
VIRGO
CAPRICORNUS
13 14
18
14
18
12 17 12
–10°
Spica
15 16 18
19
18
19
17
Antares
16
LIBRA POSITIONS OF THE PLANETS This chart shows the positions of the planets in August from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
SAGITTARIUS
except Mercury, the dot indicates the planet’s position on August 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Shaula
SCORPIUS
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
E V E N I N G
S K Y
Mars’s position on August 15, 2011
11
Saturn’s position on August 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
78
MONT HLY SKY GUID ES: HIGHLIGHTS
AUGUST NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH Northern summer nights are the perfect time to admire the galaxy we live in. In August the Milky Way rises up from Auriga and Perseus in the northeast, stretching all the way across the sky into Scutum, Scorpius, and Sagittarius in the southwest. There are many objects nestled in and around the Milky Way that can be spotted with binoculars. In addition to the Double Cluster (see p.22), be sure to look out for the globular clusters M13 and M92. A large telescope will reveal the galaxies M81 and M51.
Date
Standard time
Daylight-saving time
July 15
Midnight
1 am
August 1
11 pm
Midnight
August 15
10 pm
11 pm
September 1
9 pm
10 pm
September 15
8 pm
9 pm
Zenith 20°N
CYGNUS 40ºN
Vega Deneb
HERCULES 60ºN
PEGASUS SERPENS CAPUT
DRACO CEPHEUS
BOÖTES
ANDROMEDA
URSA MINOR
Polaris CASSIOPEIA
Arcturus
zon Hori
URSA MAJOR
Big Dipper
PISCES PERSEUS
20ºN
Capella
The Milky Way Binoculars are the ideal way to explore the star fields of the Milky Way. The glow of the Milky Way on a dark night is the collective light of billions of the galaxy’s stars.
ARIES
Horizon 40ºN
W
ES
T
H or izon
it lip Ec
c
AURIGA
60ºN
EA
ST
Castor
LOOKING SOUTH There are two must-see objects if you are looking south in the Northern Hemisphere: M27, or the Dumbbell Nebula, east of Pegasus, and M57, or the Ring Nebula, south of Cygnus. Both these planetary nebulae are enormous shells of gas ejected by Sun-like stars as they die. The Ring Nebula is so named because it looks like a smoky gray ring when it is viewed through a telescope. The Dumbbell Nebula appears as a faint gray bow-tie shape through a large-aperture telescope.
Zenith 60°N
DRACO
Deneb
40ºN
Vega
CYGNUS
20ºN HERCULES
Altair
PEGASUS
AQUILA
AQUARIUS PISCES
SERPENS CAUDA
CAPRICORNUS
OPHIUCHUS SERPENS CAPUT
tic Eclip
0 ºN Horizon 6
SAGITTARIUS
VIRGO
Antares Fomalhaut
The Dumbbell Nebula Lying east of Pegasus, the Dumbbell Nebula can be seen as a fuzzy patch through a small telescope or a pair of binoculars. A large telescope reveals its intriguing shape more clearly.
CETUS
EA
LIBRA
Horizon 40ºN SCORPIUS
ST
Horiz on
ARA
GRUS 20ºN
PAVO
LUPUS
W
ES
T
AUGUST
AUGUST SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The constellation Cygnus, the Swan, is home to two open clusters that make good, small-telescope targets. M29 sits very close to the star Sadr, Gamma (γ) Cygni. The magnitude 4.6 cluster M39 can be seen sparkling against the stars of the Milky Way. It has about 30 stars. Higher in the sky you will find Capricornus, the Sea Goat, which is home to the globular cluster M30 and Beta (β) Capricorni—a double star of magnitude 3.1 that can be seen with binoculars.
Zenith 40°S
SAGITTARIUS
20ºS CAPRICORNUS
β SERPENS CAUDA
Antares
0º
SCORPIUS
AQUARIUS OPHIUCHUS
Altair
AQUILA
LIBRA ptic Ecli
CYGNUS
SERPENS CAPUT
HERCULES
Sadr Vega Deneb
PEGASUS Horizon 40 ºS
VIRGO CEPHEUS ANDROMEDA
DRACO BOÖTES
Arcturus
W
ES
Horizon 20ºS PISCES
URSA MINOR
T
EA CASSIOPEIA
ST
0º Horizon
M39 in Cygnus The open cluster M39 covers an area of similar size to the full Moon and lies 825 light-years away. It is a nice target for binoculars or a small telescope on a clear night.
LOOKING SOUTH Sagittarius, the Archer, is now sitting high in the south, providing a feast of objects to observe. M17, the Omega Nebula, is a good target for a small telescope. It is a glowing cloud of hydrogen gas that resembles the Greek capital letter Omega (ω). The open cluster M23 and the Sagittarius Star Cloud M24 are also ideal binocular objects. A large telescope is needed to clearly see the magnitude 9 M20, also known as theTrifid Nebula.
Zenith 0°
AQUILA
SERPENS CAUDA
20ºS c ipti Ecl
SAGITTARIUS
CAPRICORNUS
AQUARIUS
OPHIUCHUS
40ºS
Antares
GRUS SCORPIUS
ARA
Fomalhaut
PAVO
LUPUS PHOENIX
TUCANA
α Centauri
OCTANS
β Centauri
Achernar CETUS
zon 0 Hori
CRUX
º
VIRGO Horizon 20ºS
EA
ST
LIBRA
ERIDANUS
CENTAURUS PICTOR
HYDRA
CARINA
WE
Canopus Horizon 4 0 ºS
Spica
VELA
ST
The Trifid Nebula The Trifid Nebula is an enormous cloud of gas 7,600 light-years from Earth. It lies in the constellation Sagittarius, and at its heart is a young cluster of stars that are causing the nebula to glow.
79
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
M
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L EO
M5 1
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LYN X
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Polaris
US
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NORTH
LOOK I N G
M81
DR
LY RA
Vega
Dip pe
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Miz
Big
M9
UL
IC E UR SA
MA JO
3
4
OR
RC
S
EN
IN
VE CAN N ES A TI CI
M
M1
M6
ER S
T
2
2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
US
ELO
Planetary nebula
R PA
S
SS
LI
CA
DA
IO
P
M
4
NG
88
3
C
10
NG
7
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86
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9
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6
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M3
EU
S M
34
TR
NG
O
IA
N
R
TH
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES Date July 15 August 1 August 15 September 1
Zeniths
September 15
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
S AS U P EG
HE
E ÖT
53
T
BO
M3
W
ES
NA RO I S CO REAL BO
H
us
AB 1
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
ES
SC
PI
9 M3
AUGUST | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
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M69
TELESCO
M28
P IU M
A CORONLIS A US T R A
M54
M22
M25
M8
M21
ARA
M6
M14
M23
M7
M16 M17 M18 M24
EN S S ERP DA U CA
S C U T UM
M26
M11
LA
S OUT H
SOUTH
A LY R
EC U HE
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
M
12
M
M4
80
MA
Zeniths
R NO
62
M
P OR SC
es ar 9 M1 Ant
US
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
10
CH
M
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ula Sha
M9
OP
S
LE
57 M
VU LP
SAGITTARIUS
SAG I T Altair
Eclip
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Alb
LO OK I N G
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M
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COP IU
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PR
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M30
CA
M
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M
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M2
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IU
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60°N
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LI
BR
C
NS
GN
US
RC U
AUGUST | NORTHERN LATITUDES
EAST UL
SUNRISE AND SUNSET ON 15TH AUGUST
US
RP E
M5
T AP U
A
CE T
TH
LU P
S CE 40°N
20°N
South
North
STAR MOTION
W
P
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T
PE
S GA
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9
GO Ecliptic
VIR
M2
CY
A UGU S T N OR T H E R N L A T IT U DE S 81
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
VIR GO M5
NA
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M24 5
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M17
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M27
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Albireo M57
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N O
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N ORTH
NORTH
LOOK I N G
OR
LYRA
Vega
UT
M2
CA
A MIN
A
18
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M1
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10
HI U HU S
RC
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UL E S
ACO
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M23
CA IS
M
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2
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EN OR E M1
M9
DR
PE
RP
T
M1
CO RO
H
W
ES
SE
us
T
P
2
O
2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
M39
L AC
ER
2
TA
M5
20°S
POINTS OF REFERENCE Horizons 0°
CA
40°S
SS
PE
IA
Date
SU
DR
GA
AN
PE
July 15 August 1 August 15 September 1
ED
N
OM
September 15
Zeniths
A
O
0°
R
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
IO
S
US
RI
UA
AQ
SE R
tur
1
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
ES
SC
PI
S
AUGUST | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
ST
A
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31 M
M2
15 M
Arc
82
TH
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FO
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AR A
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SOUTH
C AR I N A
VO LA N S
LO OK I N G
PICTOR
LMC
I UM
A PUS
PAVO
TE LESCOP
CO R O N A IS AU S T R AL
9
M20
M8
M1 M2
8
M7
2
M6
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
U
i aur
Horizons 0°
20°S
POINTS OF REFERENCE
VE
i
40°S
LA
Ga
S
UX
PU
CR
x
aur
ru Bec
αC
LU
A
ent
RM
S
NO
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ent
βC
C
PI
NU I RC I
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M19
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M2
C H AMA E L E O N
O CTAN S
US
ME N S A
UM
SAG ITTA
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4
la
M5
au
M55
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M9 2 M6
AUGUST | SOUTHERN LATITUDES
EAST T RO
NI
GR
IC
S M6
Sh
M4
are Ant
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M80
cru
RA 0°
U
RU
S
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Zeniths
NG
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Ecliptic
83
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TH
M
UA m Fo
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IS U SC PI TRIN S AU S
30
RA 20°S
40°S
South
North
STAR MOTION
ES
PR
W
AQ GO VIR
M
Ecliptic
Spica
CA
HY D
IC OR
A UGU S T S OU T H E R N L A T IT U DE S 83
WEST
84
MO NT H LY S KY GUID ES: OVERVIEW S
SEPTEMBER
PEGASUS
The nights are darker now in the Northern Hemisphere, making it a good time to admire the constellations along the Milky Way. In the Southern Hemisphere, the region around the Milky Way’s center moves to the west.
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
7
Epsilon (ε) Pegasi, or Enif, 2.4
Pegasi
Peg
September–October
You can easily spot the constellation Pegasus, the Winged Horse, especially in late summer and fall in the Northern Hemisphere. Its main body is made up of the large asterism known 20º as the Great Square of Pegasus. This square helps locate the constellation Andromeda, where you 10º can find the magnificent spiral galaxy M31, the Andromeda Galaxy.
NORTHERN LATITUDES the east. The roughly triangular constellation Capricornus, the Sea Goat, lies in the south.
THE STARS Looking high up in the sky, you will spot the constellation Cepheus, representing King Cepheus. Delta (δ) Cephei, a variable star in Cepheus, is a popular target for amateur astronomers. Its brightness varies between magnitude 3.5 and 4.4 every 5 days and 9 hours. Toward the west, the stars of the Summer Triangle are still visible, while the constellations Cassiopeia and Andromeda are visible in
Size ranking
LACERTA
22h
23h
ANDROMEDA
π
NGC 7331
0h
β
78
ο
Scheat
ψ GREAT SQUARE OF PEGASUS
CYGNUS
η
72
τ
υ
32
κ
μ λ
56
ι
2
51 1 9
α
Algenib
γ
PEGASUS
Markab
70
ξ
M15
31
ζ
ε Enif
θ 35
ν
EQUULEUS
0º
SIGHTS OF INTEREST If you are up for a real challenge this month, try hunting down the North America Nebula, NGC 7000. It is hard to detect from light-polluted skies, but with binoculars it can be seen from dark skies, sitting near
AQUARIUS
the star Deneb in Cygnus. If you want to marvel at one of the jewels of the night sky, look for the beautiful globular cluster M15 using
binoculars. It can be seen near the star Enif, or Epsilon (ε) Pegasi. The open star cluster M39 in Cygnus is another deep-sky object worth observing through binoculars or a small telescope.
6 AM 9 AM
3 AM
Capella NOON
MIDNIGHT
Castor 30°
GEMINI
Pollux
20°
11
13
LEO
14
15
17 17
19
11 Regulus
ARIES
Aldebaran
CANCER
11
Hyades
PISCES
15 Betelgeuse
14 15
16
Pleiades
12
12
17 10°
TAURUS
13
Procyon
Bellatrix
0° Mira Rigel
–10°
–20°
–30°
M O R N I N G POSITIONS OF THE PLANETS This chart shows the positions of the planets in September from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
S K
Y
except Mercury, the dot indicates the planet’s position on September 15. Mercury is shown when it is at greatest elongation (see p.125). For the specific dates, refer to the Almanac.
19 18
PISCES
17 16 15
14 13
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
12
Neptune
11
EXAMPLES
11
Mars’s position on September 15, 2011
CETUS 11
Saturn’s position on September 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125) URANUS
S E P T E MB E R
85
SOUTHERN LATITUDES constellations, including Pisces, the Fishes; Cetus, the Whale; and Eridanus, the River.
THE STARS If you are observing from the Southern Hemisphere this month, be sure to enjoy the rich regions of Scorpius and Ophiuchus before they sink below the western horizon. Just above them lies a rich region around the heart of the Milky Way galaxy, brimming with star clusters and bright nebulae. In contrast, the eastern half of the sky is relatively empty, though you can still find several
relatively large telescope to view this nebula. There are two interesting binocular targets in the sky at the moment—the globular cluster M2 in Aquarius, near the star Beta Aquarii, and another globular cluster M15, in Pegasus.
globular cluster M22. The constellation Aquarius, the Water Carrier, sits almost overhead. You can see several deep-sky objects there, including the interesting planetary nebula NGC 7293, also known as the Helix Nebula. You will need dark skies and a
SIGHTS OF INTEREST This month be sure to enjoy the sights of Scorpius, Sagittarius, and Scutum before they disappear below the horizon. The most spectacular objects to look for in these constellations include M8, the Lagoon Nebula; the open clusters M6 and M7; and the
P I S C I S A U S T RI N U S Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
60
Alpha (α) Piscis Austrini, or Fomalhaut, 1.2
Piscis Austrini
PsA
September–October
Also known as the Southern Fish, Piscis Austrinus is one of the smaller constellations in the night sky and lacks any prominent deep-sky objects. You can find it nestled between the constellations Grus, Aquarius, Capricornus, and Sculptor. Its brightest star is the blue-white colored Fomalhaut, which sits at the mouth of the fish. Fomalhaut lies at a distance of 25 light-years from Earth.
22h
23h
AQUARIUS
ε
CAPRICORNUS PISCIS AUSTRINUS
λ
α
–30º
Fomalhaut
δ γ
β
τ
μ υ
GRUS –40º
ι
MICROSCOPIUM
The Small Magellanic Cloud Lying in the constellation Tucana in the Southern Hemisphere, the Small Magellanic Cloud can be found close to the beautiful globular cluster 47 Tucanae, also known as NGC 104.
NOON
30° 3 PM 9 PM
20° 6 PM
Arcturus 10°
Altair
AQUARIUS
11 16
11
OPHIUCHUS
VIRGO
15
0° 19
16 12
CAPRICORNUS 13
14
16 18
19
17
18
18
LIBRA 18
17
16
SAGITTARIUS 15
14
13
12
Shaula
11
AQUARIUS
14
–10°
13 18 –20°
Antares
16 19
19
15 14
12
17
SCORPIUS
NEPTUNE
E V E N I N G
Y S K
–30°
86
MONT HLY SKY GUID ES: HIGHLIGHTS
SEPTEMBER NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH In the northern skies, trace the constellation Draco, the Dragon, weaving between the constellations Ursa Minor, Cepheus, and Hercules. At the tip of the dragon’s tongue lies the double star 16 and 17 Draconis, which can be spotted with just a pair of binoculars. Nu (ν) Draconis in the dragon’s head is also an interesting double star in binoculars. Sitting a little way above the bright star Vega, the multiple star system Epsilon (ε) Lyrae, is an excellent target for a telescope.
Date
Standard time
Daylight-saving time
August 15
Midnight
1 am
September 1
11 pm
Midnight
September 15
10 pm
11 pm
October 1
9 pm
10 pm
October 15
8 pm
9 pm
Zenith 20°N
PEGASUS 40ºN CYGNUS
Deneb Epsilon (ε) Lyrae
60ºN
ANDROMEDA
PISCES
Vega
ν
CEPHEUS
DRACO
CASSIOPEIA
16,17 Draconis
ARIES
Polaris
URSA MINOR
HERCULES
PERSEUS CETUS
Horizon 20ºN
SERPENS CAPUT
Big Dipper
URSA MAJOR Horizon 40ºN
BOÖTES
Epsilon (ε) Lyrae Also known as the “Double-Double”, with binoculars this quadruple star appears as a pair, while a small telescope shows the two stars’ twin components.
W
Capella
AURIGA
Arcturus
ES
GEMINI
T
TAURUS
itc lip Ec
Aldebaran
EA
Castor Horizon 60ºN Pollux
ST
LOOKING SOUTH In the south the impressive Andromeda Galaxy, M31, sits in the heart of Andromeda. It is easily visible to the naked eye from a dark sky site. Binoculars reveal it as a fuzzy ellipse, while a small telescope shows it more clearly. The Coathanger asterism, or Brocchi’s Cluster, lies between Cygnus and Aquila in the east, and is easily visible through binoculars. The double star Gamma (γ) Equulei, west of the constellation Aquila, sits near the star Enif in Pegasus and is also a good binocular target.
Zenith 60°N
Deneb ANDROMEDA
40ºN CYGNUS
Vega 20ºN
PEGASUS
ARIES
Enif Altair Gamma (γ) Equulei
HERCULES
AQUILA
Ecliptic
AQUARIUS PISCES SERPENS CAUDA
CAPRICORNUS CETUS
0 Horizon 6
ºN
Fomalhaut
OPHIUCHUS SAGITTARIUS
GRUS
The Coathanger Ten stars make up the famous shape of the Coathanger, south of Cygnus. The stars of this open cluster are not near each other in space; the shape is a chance alignment.
Horizon 40ºN ERIDANUS
EA
ST
PHOENIX
SCORPIUS
Antares
W
Horiz on 20º N
PAVO TUCANA
ES
T
S E P T E MB E R
SEPTEMBER SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The globular cluster M15 sits southwest of the star Enif, Epsilon (ε) Pegasi, in Pegasus. This dense cluster can be picked out with binoculars, and a small telescope shows it clearly. M15 is thought to be 13.2 billion years old. Several deep-sky objects lie in the northeast, in the constellation Aquarius. The globular cluster M2 appears as a fuzzy star through binoculars, and the planetary nebula NGC 7293, the Helix Nebula, appears as a faint fuzzy disc through a small telescope.
Zenith 40°S
CAPRICORNUS
Fomalhaut
20ºS
AQUARIUS SAGITTARIUS
0º Ec li
AQUILA SERPENS CAUDA
pt ic
Enif CETUS
Altair
PEGASUS CYGNUS
PISCES
Deneb
OPHIUCHUS
ANDROMEDA
HERCULES
Vega 40 izon Hor
ºS
CEPHEUS CASSIOPEIA
ARIES
Horizon 20ºS
W
ES
T
Hori zon
DRACO
PERSEUS
EA
0º
ST
M15 in Pegasus The globular cluster M15 is roughly 175 light-years in diameter and 30,000 light-years from Earth. A 150mm (6in) telescope reveals many of the cluster’s sparkling stars.
Polaris
LOOKING SOUTH The globular cluster 47 Tucanae is a must-see target in the September southern skies, lying to the south of the constellation Tucana. It is visible to the naked eye as a hazy star, while a small telescope shows its bright center and many of its glittering stars. This cluster is 15,000 light-years away. Other visible targets include the globular clusters M22, NGC 6397, and M4, in Sagittarius, Ara, and Scorpius respectively. The open clusters M6 and M7 in Scorpius are also visible.
Zenith 0°
Ecliptic 20ºS
AQUILA
CAPRICORNUS
AQUARIUS
40ºS
Fomalhaut
GRUS
SERPENS CAUDA
SAGITTARIUS
CETUS PHOENIX TUCANA ARA
PAVO
Achernar
OPHIUCHUS SCORPIUS
ERIDANUS
Horizon 0º
Antares
OCTANS
α Centauri β Centauri Horizon 20ºS
EA
ST
Hori zo
n 40 ºS
PICTOR
CRUX CARINA
Canopus PUPPIS
LIBRA
WE CENTAURUS
VELA
LUPUS
ST
M4 in Scorpius The globular cluster M4 is a beautiful sight in the constellation Scorpius. Sitting close to the star Antares, Alpha (α) Scorpii, it is a lovely target for binoculars or a small telescope.
87
WEST ctu Ar rus
NA RO L I S CO R E A BO
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Miz
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5
Variable star
ACO
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Big D
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R
A MA J OR
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Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
M39
CE
S
LA
CE P H EU
Polaris
M81
Diffuse nebula
RT
M5
2
CAS
SI O
AN
A
M1
PEI 03
E LO
LYNX
C AM
Planetary nebula
NG
M
31
C
9
IS
86
AL
84
NG
C8
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lla pe Ca
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POINTS OF REFERENCE
P
I
G
IN
RI
M
AU
GE
M
38
N
O
M
R
37
TH
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES Date August 15 September 1 September 15 October 1
Zeniths
October 15
Horizons 60°N 40°N 20°N
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
RC
M3
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NORTH
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SEPTEMBER | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
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MO NT H LY S KY GUID ES: SKY GUID ES 88
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0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
IU M
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
M
2
5
69
M2
M
28
AR
A
17 M 8 1 M 24 M
Zeniths
NA S RO A L I O C TR S AU
54
M2
M
26
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M
11
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COP
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60°N
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M
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M29
D EL P
M I C RO S C O P I U M
M30
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M2
M15
A Q UA R I U S
RINU S
SUS
I S AU S T
GRUS
PIS C
PE
27
16 M
14 M
H
SEPTEMBER | NORTHERN LATITUDES
EA
PI
8 M
0 M1
H M
OP M
6
40°N
20°N
South
North
STAR MOTION
W
2 M1
9
IU C 9
SC OR
S
T
EAST
AN U
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M1
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2
TU
M6
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M
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are
s
Ecliptic
Ant
CYGNUS
S E PTE M BE R N OR T H E R N L A T IT U DE S 89
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
M1
M1 M 92
SC
S ER Al
6
PR 7
N US
EQ U
M
PE
HI
0
UC
NS
UM
HU
CA
U AQ
IL A INUS
HE
11
Deneb
U LE US
M2
M15
M39
NGC 7293
LACERTA
RC UL ES M 13
C E P H EU S
N O
R
S
N ORTH
NORTH
LOOK I N G
LP H
M29
DE
OR IC tair
M2
CYG N US
GI TT A
LA
SA EC U
Albi reo
CA
UT
V
UL P
AC O
M57
DR
A
Veg a
LYR
M2
OP
AP
UT
T
4
A UD
2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
M52
Planetary nebula
AS
E c li p
E DA
US
RO M
PEG
AN D
1
PE
M3
SIO
03
tic
M1
C AS
IA
20°S
POINTS OF REFERENCE Horizons 0°
NG
C8
69
40°S
E
84
SC
C8
PI
NG
M
RS
33
PE
TR
EU
N
O
0°
R
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES Date August 15 September 1 September 15 October 1 October 15
Zeniths
Mir a
6
2
SC
H
W
E ST
M1
P EN 1
S
S RI U UA
AQ
SEPTEMBER | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
40°S
EAST
S
AR
IE S
TU
CE
ST
NG
UL UM
A
34 M
E
IA
S
S ER
90
F
N OR
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CO
M LU
H
EA
BA
T ST
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PP
M
PU
IU
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Ca no pu
AN
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PIC
TOR
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RA
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SMC
S CARI N A
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S
5
63
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CRU
A
X
rux Bec rux Gac
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βC
ent
S i aur
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RA
M25
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aur ent αC
UM GUL L E N A I TR TR A AU S
C NG
NA S RO L I CO STRA AU M P IU O C ES T EL 97
M24 M17
8 M2 M7
M5
G
4 M5
IU
TT AR
I
SA
A MUS C
A PU S
PAVO
S OUT H
SOUTH
VE L A
LO OK I N G
VO L A N
C H AMAE L E O N
RN
PIUM
I N D US
MICROSCO
OCTANS
S
ANA
G RU
TUC
MENS A
104
RU S
NGC
LMC
H YD
Ach ern ar
NI
R
CA
O P R IC
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE 40°S
NO
S
SEPTEMBER | SOUTHERN LATITUDES
EAST OL
AX
UM
ID
PH
P
OR
S ER
TO
AU P I S C I S TR S I NU S
M30
P OR
S
C5
139
Zeniths
NG
CE
IU
0°
M19
US
M9
R AU NT
MA
SC
R
la
3 M2
M16 M21 M18
M8
ha u
au t
alh
Fo m M22
9 M6
US
2 M6
UL tar es An
SO
U
TH
US
M4
P LU
M
SC 20°S
40°S
South
North
STAR MOTION
W
TU 80
UA
ES T
CE OP
H
IU C
HU
S RA
AQ
LI B
RI
Ecliptic
S E PTE M BE R S OU T H E R N L A T IT U DE S 91
WEST
92
MO NT H LY S KY GUID ES: OVERVIEW S
OCTOBER
PERSEUS
In the Northern Hemisphere, the main attractions this month are Pegasus and Andromeda. In the Southern Hemisphere, these constellations sit in the north, while the Small Magellanic Cloud lies in the south.
Lyra can be found very easily by locating its brightest star, the magnitude 0.0 Vega. SIGHTS OF INTEREST If you have a small telescope or a pair of binoculars the Andromeda Galaxy, or M31, in Andromeda is a wonderful target to look at. M31 is visible to the naked eye from dark skies. Binoculars show the open cluster M52 in Cassiopeia.
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
24
Alpha (α) Persei, or Mirphak, 1.8
Persei
Per
November–December
Perseus, the Hero, sits among the beautiful star fields of the Milky Way Galaxy between Andromeda and Auriga. It is an interesting constellation that contains some wonderful deep-sky objects to observe with a small telescope or a pair of binoculars, including the open cluster M34 and the Double Cluster, NGC 884 and NGC 869.
NORTHERN LATITUDES THE STARS Standing under the cold, crisp October night sky, you can see the Great Square of Pegasus high up in the sky. You can easily spot the constellation Andromeda sitting next to it, while a loop of stars known as the Circlet is visible directly beneath the asterism. The constellations Aquarius, Pisces, and Cetus can be located nearby. Turn around and look toward the north to find the constellations Cepheus, Cassiopeia, and Perseus. Cygnus, the Swan, and Lyra, the Lyre, are visible toward the west. Although a small constellation,
Size ranking
5h 2h
4h
3h
CAMELOPARDALIS
η
NGC 869 NGC 884
4
γ 50º NGC 1528
λ μ
Capella
AURIGA
MELOTTE 20 34
δ
ψ σ
48
53
M76
τ Mirphak
α ι
φ
θ
κ 40º
58
32
ν ε
52
Per A
PERSEUS 54
NGC 1499
30º
ζ
β ωρ
Algol
40
ο
π 16
NGC 1342
ξ
ANDROMEDA M34
12
TRIANGULUM
24 17
ARIES
TAURUS
the direction of the patch of sky between Orion’s head and Gemini’s feet. The best time to look is after midnight, when this region of sky has risen higher above the horizon.
METEOR SHOWER The Orionid meteor shower reaches its peak around October 21. Under good conditions during the peak you can expect to see around 25 meteors every hour, shooting from 6 AM
3 AM MIDNIGHT
9 AM
Capella
NOON
Castor Pollux
TAURUS
GEMINI 13
LEO
20°
11
10°
12
VIRGO 17 0°
17
15
15
Aldebaran
Hyades
Regulus
CANCER
Betelgeuse Procyon
15
Bellatrix
15
14
Mira
16 Rigel
–10°
–30°
11
19
11
–20°
ARIES
12
14
13
Pleiades
M O R N I N G
POSITIONS OF THE PLANETS This chart shows the positions of the planets in October from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
–40°
except Mercury, the dot indicates the planet’s position on October 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
Mars’s position on October 15, 2011
11
Saturn’s position on October 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
S K Y
OC T OB E R
SOUTHERN LATITUDES THE STARS After the wonderfully rich views of the southern winter, October night skies look rather empty. However, this does not mean there is nothing to see. Looking south, you can locate the constellations Phoenix, Grus, Tucana, Pavo, and the long and winding Eridanus. The constellation Sagittarius, the Archer, lies low in the west. There are several bright stars to help you navigate the sky. In the south, look out for the magnitude
The Circlet This asterism is formed by a ring of seven stars that make up the head of one of the fish in the constellation Pisces. MIDNIGHT
E RI D A N U S
1.2 star Fomalhaut, almost directly above you in the constellation Piscis Austrinus. A little lower down in the south at one end of Eridanus shines Achernar, or Alpha (α) Eridani, while the bright star Altair, in Aquila, twinkles away in the west. Aquarius is high up in the northern part of the sky. Pegasus is also on view with its famous square practically due north. SIGHTS OF INTEREST In the Southern Hemisphere the night sky offers several objects that make good targets for even modest amateur equipment. Look south to find the constellation Tucana, the Toucan. Within the boundaries of this constellation you can see 47 Tucanae, or NGC 104, one of the best globular clusters in the night sky. With the naked eye it appears as a slightly fuzzy star. Near 47 Tucanae lies the galaxy known as the Small Magellanic Cloud, or SMC, which is a great target for a small
18
17
16
15
14
9 PM
13
12
Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
6
Alpha (α) Eridani, or Achernar, 0.5
Eridani
Eri
November–January PISCES 4h
5h
Eridanus, the River, winds its way across the night sky, starting near the feet of Orion. It then meanders across the sky toward Cetus before passing the constellations Horologium, the Clock, and Caelum, the Chisel. Its brightest star, Achernar, Alpha (α) Eridani, has a magnitude 0.5, and marks the end of this celestial river. Eridanus has few clusters or nebulae within it but contains some interesting double stars, such as 32 Eridani and Theta (θ) Eridani.
3h
45
μ
ν
32
β ω ψ λ
ο2 γ
NGC 1535
η
π
64 53
ζ
ε
δ
39
–10º
CETUS
17
ο1
ERIDANUS
τ1
NGC 1300
54
τ
6
τ9
τ5
τ4 15
τ
τ2
3
τ8 υ1
–30º
FORNAX
υ2 υ
4
υ3 ι
θ1
–40º
CAELUM
κ –50
˚
φ
HOROLOGIUM
telescope or a pair of binoculars, DORADO PICTOR and can also be seen with the Achernar naked eye. A hop over the constellation Galaxy, M31, in the constellation Hydrus, or the Little Water Snake, Andromeda, as well as the takes you to the constellations spiral galaxy M33, visible through Dorado and Mensa, where you binoculars or a small telescope in will find the Large Magellanic the constellation Triangulum. The Cloud, or LMC. It can be seen Andromeda Galaxy is the closest with the naked eye and is a fine major galaxy to the Milky Way, sight through a telescope. Turning and twice as large. your attention to the northern sky, you can find the Andromeda NOON
NEPTUNE 19
93
11
χ
α
AQUARIUS 20°
3 PM 6 PM
Arcturus
PISCES
10° Altair
AQUARIUS 0°
OPHIUCHUS
VIRGO 12 11 13 19
18 15 17
18 19
CAPRICORNUS
16
19
16
18 14
Antares
PISCES
17
12 13
13
19
16
SAGITTARIUS
15 14
18
–10°
–20°
12
LIBRA
19 18
14 16
17
–30°
Shaula
13 12
–40°
11
SCORPIUS
CETUS
E URANUS
V
E
N
I N G
S K Y
94
MONT HLY SKY GUID ES: HIGHLIGHTS
OCTOBER NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH As the Summer Triangle (Vega, Deneb, and Altair) moves to the west, the Milky Way arches overhead and some winter constellations start peeking over the horizon. Look out for the Double Cluster in Perseus (see p.22) and the open clusters M36, M37, and M38 in Auriga, rising in the east. The Hyades and Pleiades star clusters in Taurus start coming back into view and the open clusters M52, NGC 457, and M103 high in the sky in Cassiopeia are also worth finding. These are all good binocular targets.
Date
Standard time
Daylight-saving time
September 15
Midnight
1 am
October 1
11 pm
Midnight
October 15
10 pm
11 pm
November 1
9 pm
10 pm
November 15
8 pm
9 pm
Zenith 20°N
PEGASUS
40ºN
PISCES ANDROMEDA ARIES 60ºN
Deneb
Ecliptic
CYGNUS
CASSIOPEIA
CEPHEUS
AQUILA
PERSEUS TAURUS
Vega Polaris Capella
URSA MINOR
HERCULES DRACO
AURIGA
Aldebaran
Horizon 20ºN
ORION
OPHIUCHUS
Big Dipper
The Auriga Clusters Use binoculars to look out for the open clusters M36, M37, and M38. A telescope also shows the loose open cluster NGC 2281 nearby, which contains around 30 stars.
GEMINI
W
Betelgeuse
Castor
Horizon 40ºN
Pollux
ES
T
BOÖTES
EA
URSA MAJOR
ST
Horizon 60ºN
LOOKING SOUTH While the beautiful Andromeda Galaxy, M31, is still on show this month, do not overlook another interesting galaxy close by. M33, or the Triangulum Galaxy is just above the constellation Aries, and can be glimpsed with the naked eye from a very dark sky site. A pair of binoculars or a small telescope will show this beautiful spiral galaxy’s misty, oval form. If you are observing with a telescope, make sure to spot the lovely double star Gamma (γ) Arietis in the nearby constellation Aries.
Zenith 60°N
CASSIOPEIA
ANDROMEDA
40ºN
Deneb CYGNUS PERSEUS 20ºN ARIES
PEGASUS
γ PISCES
TAURUS
Eclip tic
AQUARIUS
Altair CETUS
Aldebaran CAPRICORNUS
0 ºN Horizon 6
ORION
AQUILA
Fomalhaut GRUS
PHOENIX
The Andromeda Galaxy Through a small telescope M31, in the constellation Andromeda, appears as a fuzzy gray ellipse with a brighter core. Larger apertures will help discern the galaxy’s dark, dusty lanes.
Horizon 40ºN
Rigel
EA
ERIDANUS
ST
SAGITTARIUS
W
Achernar Horizon
20ºN
SERPENS CAUDA
TUCANA
ES
T
OC T OB E R
OCTOBER SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The double star Almach, Gamma (γ) Andromedae in the constellation Andromeda, is a lovely target for a small telescope when looking north. One of the stars has an orange tint, while the other is a beautiful blue. In the same constellation, quite close to Almach, is the magnitude 5.5 open cluster NGC 752. Binoculars or small telescopes reveal it covering an area larger than the full Moon. Finally, be sure to track down M31 in Andromeda and M33 just above Aries.
Zenith 40°S
Fomalhaut 20ºS CAPRICORNUS
0º
AQUARIUS
CETUS
ERIDANUS
PISCES
Altair
t ic lip Ec
PEGASUS
ANDROMEDA Horizon 40ºS
CYGNUS
TAURUS
ARIES
AQUILA
Almach
CASSIOPEIA
Deneb OPHIUCHUS
Aldebaran
W
HERCULES
ES
ORION
PERSEUS
Horizon 20ºS CEPHEUS
Vega
T
Capella
DRACO
Polaris
EA
AURIGA
ST
NGC 752 Composed of around 70 stars, the loose open star cluster NGC 752 is a fine sight in a small telescope using a low magnification. It can be found north of Andromeda’s star Almach in the east.
Horizon 0º
LOOKING SOUTH Two of the celestial showpieces of the southern skies can be seen this month: the Large and Small Magellanic Clouds. These galaxies lie relatively close in space to the Milky Way. The Small Magellanic Cloud (SMC) in Tucana can be seen with the naked eye, as can the Large Magellanic Cloud (LMC), which is a magnificent sight on the Dorado–Mensa border. Binoculars or small telescopes reveal many star clusters and patches of nebulosity within the LMC.
Zenith 0°
AQUARIUS 20ºS
ic pt
Ec li
Fomalhaut
CETUS
40ºS CAPRICORNUS PHOENIX GRUS AQUILA
Achernar ERIDANUS
TUCANA SAGITTARIUS PAVO OCTANS Horizon 0º
ARA
PICTOR
Rigel Canopus PUPPIS Horizon 20ºS ORION CANIS EA ST MAJOR
SCORPIUS OPHIUCHUS
CENTAURUS
CARINA
α Centauri Antares
β Centauri VELA Horizon 40ºS
CRUX
LUPUS
WE
ST
Small Magellanic Cloud (SMC) The irregular galaxy known to astronomers as the SMC sits in the constellation Tucana. Visible to the naked eye, it stretches roughly seven times the Moon’s apparent diameter across the sky.
95
WEST H
W
M 13
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M29
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LA
CE
H
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CE P
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M52
ANDROMEDA
E US
SA MI NOR
Big Dipper
M1
NG
C
7
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IA
NG
45
PE
86
C
9
NG
IS
N O
R
L EO
A JOR
SIO
03
CAS
M81
U R SA M
N ORTH
NORTH
LOOK I N G
VE NA TI C I
Mizar
9
M51
CAN
M3
NU
LYR M9
B
OÖ TE S
C YG
HE
ES T
T
S
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
88
4
CA
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OR
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S
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POINTS OF REFERENCE
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81
AU
22
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M
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37
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11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES Date September 15 October 1 October 15 November 1
Zeniths
November 15
Horizons 60°N 40°N 20°N
ix
latr
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
e
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elg
Bel
OR
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Bet
V U LP E C
S 3
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M1
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35 M
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OCTOBER | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
lu
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A
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Hyade sto
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MO NT H LY S KY GUID ES: SKY GUID ES 96
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Fomalhaut
A Q UA R
T UCA N A
S C U L P TO R
LO OK I N G
CES
PE G A S
R IN
US
5
M3
0
M2
M1
MI C
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
D
IU
M
P
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NU
S
Zeniths
OR RIC
Horizons 60°N 40°N 20°N
US
OP
CA
US
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US
HI
ta Al
M27
P EL
AQ
GIT TA SA LE
IN D
POINTS OF REFERENCE
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OCTOBER | NORTHERN LATITUDES
H
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20°N
South
North
STAR MOTION
W
3
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M
TU
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ORI UL
5
M17
Ecliptic
M2
TR G IAN 22
M3
WEST
O C TO BE R N OR T H E R N L A T IT U DE S 97
MO NT H LY S KY GUID ES: SKY GUID ES
WEST VU
M11
ir
HI
b
15
RI M
M2
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US Den e
M5
EC
R LY M39
US
AC O
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DE 27
GN U
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Variable star
GA S US
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PE
LA
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M31
C A SS I OP E I A
A N D RO M E D A
M52
M103
N ORTH
NORTH
LOOK I N G
EPHE U S
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
P IS
CE
S
NGC
M3
3
TR I
84
2
C8
C 75
NG
NG
869
AN
CE
GU
A
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DA
40°S
LO
M LU
ME
M34
CA
20°S
POINTS OF REFERENCE Horizons 0°
RS
S
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EU
Ecliptic
PE
L IS
45
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N
0°
R
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
TH
es
n
1 am
Midnight
11 pm
10 pm
9 pm
40°S
Ecliptic
Daylight-saving time
ara
US OBSERVATION TIMES Date September 15 October 1 October 15 November 1 November 15
Zeniths
rix
Bellat
ION
OR
AQ
I TT A
A SA
T
Al bir eo
UL A
ES
4
EAST
U IL
LP
HU
H
W
3
eb
Ald
AQ
IU C 1
2
OCTOBER | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
ad
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GA
RI
ST
AU
S Ca
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A
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Mir a
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SOUTH
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Acrux
AP US
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RO
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AU R CE NT
US
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S
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE
i aur ent αC
IN U
M LU GU L E N T R IA ST R A AU
S
C I RC
DU
C MI
O PAV
CIS S PI S I NU ST R AU
MUS C A
OCTANS
NGC 104
TU CA N A
CH A MAE L E O N
US
OE
LO OK I N G
HY DR
SA
I NA
MEN
Ach ern ar
LMC
LUM
IU
ICU
RO LO G
RE T
HO
X
H
PT OR
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M30
OCTOBER | SOUTHERN LATITUDES
OCTOBER
ST
PP
s
pu
no
U Ca
U
SUNRISE AND SUNSET ON 15TH
R
EA
M LU CO
TH
PU
M
S
NA
UL
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NU 40°S
AR
A
RM
A
Zeniths
NO
S
M
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PU
0°
LU
NA I S RO M CO TRAL IU S OP AU C S LE TE
PR ICO R
CA
SC
M IU
CO P
2 M2
55 M
GI
SA
IU TT AR
7
la au Sh
U
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M16 M17 M18 M24
3 M2
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M26
8 M
TUM
SCU M2 1 2
M2 5
M2 8 6
ut
ha
69 M
EAST
M
2
SM ANI
P
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SC OR
LE
IU S
OR
P
40°S
South
North
STAR MOTION
20°S
W
CA
M6
EN
RP
AN
SE
OR
D RI
M1 9
el
A
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Rig
F
M4
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M9
TU
Ecliptic
Ant ares
CE
ES T
al
O C TO BE R S OU T H E R N L A T IT U DE S 99
WEST
100
MO NT H LY S KY GUID ES: OVERVIEW S
NOVEMBER We are now deep into the wonderful dark nights of fall in the Northern Hemisphere, where the constellations Orion, Taurus, Auriga, and Gemini are visible. In the Southern Hemisphere, Cetus, Eridanus, and Aquarius are high in the sky.
T A U RU S
SIGHTS OF INTEREST In the Northern Hemisphere November’s skies contain the lingering sights of summer, including M31 and M33, as well as some new objects. The open clusters NGC 457 and NGC 663 in the “W” shaped constellation Cassiopeia make excellent binocular
Brightest star
Genitive
Abbreviation
Highest in sky at 10pm
17
Alpha (α) Tauri, or Aldebaran, 0.85
Tauri
Tau
December–January
The stars of Taurus, the Bull, are easy to locate in the night sky because they are anchored around the bright “V” shape of the Hyades star cluster and the bright star Aldebaran. Both the Hyades and Pleiades star clusters can be seen with the naked eye. Another remarkable deep-sky object in Taurus is M1, the Crab Nebula.
NORTHERN LATITUDES THE STARS Two interesting constellations, Perseus and Cassiopeia, are almost overhead this month. Looking south, the constellations Pegasus and Andromeda are sitting high in the sky. In the east, the grand constellations Orion, Taurus, and Auriga are also visible.
Size ranking
targets. A small telescope shows the glittering pair of clusters in Perseus listed as NGC 869 and NGC 884, collectively known as the Double Cluster. There are also several fine open clusters visible in Auriga.
4h
5h
AURIGA
6h
PERSEUS
30º
βAlnath
136
GEMINI
132
ι
M1
ζ
114
109
υ
37
κ
126 Aldebaran
ε α
ARIES
ω
NGC 1647
119
Pleiades M45
τ
NGC 1746
20º
φ
TAURUS
139
Ecliptic
T
Hyades
5
134
λ
90
ORION
10º
88 Betelgeuse
μ
ξ
47
ν
ο CETUS
10
0º
ERIDANUS
a point south of M45. Another meteor shower, the Leonids, peaks around November 17. At its peak you can observe up to 10 meteors an hour, shooting from the direction of Leo’s head.
METEOR SHOWERS Look for the peak of the Taurid meteor shower during the first week of November. If the skies are clear and dark you may see 10 meteors an hour, coming from
3 AM
MIDNIGHT
6 AM
Capella
9 AM
Castor Pollux
GEMINI Pleiades
NOON
13
CANCER LEO
Arcturus
12
Hyades
11 10°
Regulus 13
Betelgeuse Procyon
0°
15 12
VIRGO 11 –10°
17
19
12 19
20°
30°
TAURUS
Aldebaran
14
13
17
LIBRA
14
15
Bellatrix
15
17 16
Rigel
18
13
POSITIONS OF THE PLANETS This chart shows the positions of the planets in November from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
40°
except Mercury, the dot indicates the planet’s position on November 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
50°
11
Mars’s position on November 15, 2011
11
Saturn’s position on November 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
N OV E MB E R
101
SOUTHERN LATITUDES THE STARS The constellations Eridanus and Cetus sit right above you this month. Eridanus, the River, is naturally long and winding and its end is marked by the bright star Achernar, which can be seen high in the sky almost due south. The constellation Phoenix sits close to Eridanus and below it, toward the direction of the south celestial pole, are the constellations Reticulum, the Net; Hydrus, the Little Water Snake; Tucana, the Toucan; and Octans, the Octant. In the east you can locate Canis Major, which is hard to miss as it is home to the blazing star Sirius. Also coming into view in the east are
Orion and Taurus. It is easy to identify Orion, as it contains the bright stars Betelgeuse, Alpha (α) Orionis, and Rigel, Beta (β) Orionis. Look north to find the constellations Andromeda, Pisces, and Aries. SIGHTS OF INTEREST Because Cetus is high in the sky, a large telescope will show you the interesting spiral galaxy M77, sitting very close to the star Delta (δ) Ceti. The beautiful Magellanic Clouds should be your next target. The Large Magellanic Cloud, or the LMC, sits across the border between the constellations Dorado, the Goldfish (or Swordfish), and Mensa, the Table Mountain. A small telescope is all you need to explore the sparkling star clusters as well as the Tarantula Nebula, or NGC 2070, nestled within the LMC. Meanwhile, a short distance away in the constellation The variable star Mira Omicron (ο) Ceti, more popularly known as Mira, is a variable star in the constellation Cetus. Its brightness changes over time as it pulsates.
CETUS Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
4
Beta (β) Ceti 2.0
Ceti
Cet
October–December
Cetus, the Sea 10º 3h μ ξ2 Monster or Whale, λ can be found in the ν κ α Menkar night sky positioned γ between Pisces and 0º δ M77 Eridanus. The ο brightest star in this constellation, Beta ERIDANUS (β) Ceti, is called –10º Diphda and has a ε ρ π 2.0 magnitude. The σ “back” of Cetus is marked by the famous variable star –20º Mira. Cetus is also home to the spiral galaxy M77, the brightest Seyfert galaxy.
Ecli
ptic
0h
20 Mira
CETUS
θ ζ
ι
φ
η
3
NGC 246
46
τ
6
β Diphda
υ
7
2
56
Looking toward the northeast, the Hyades and Pleiades open star clusters make excellent binocular targets. Also look for the stunning spiral galaxy M33 and the glowing ellipse of Andromeda Galaxy, or M31, through a telescope.
Tucana, you can see the Small Magellanic Cloud and the globular cluster NGC 104, or 47 Tucanae. These are wonderful binocular or small telescope targets. Both the Large and Small Magellanic Cloud can be seen with the naked eye. URANUS
9 PM
PISCES
2h
ξ1
NEPTUNE
19
PISCES
18 17
19
18
16
17
16
15 14
15
14
13
13
12
12
11
11
6 PM
AQUARIUS
ARIES
CETUS 3 PM
PISCES
11
10°
Altair
AQUARIUS
0°
Mira
OPHIUCHUS –10°
CAPRICORNUS 18
14 17
16 19
E
V
E
16
14
18 16 13
11
12 19
17
15 19 11
18
Antares
Fomalhaut
N
I N
SAGITTARIUS
–20°
–30°
Shaula
G
S
14
18
–40°
K
Y
SCORPIUS –50°
10 2
MONT HLY SKY GUID ES: HIGHLIGHTS
NOVEMBER NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH Be sure to savor the sights of Cygnus, the Swan, before the constellation starts to sink below the horizon. A small telescope will show its beautiful double stars Omicron-1 (ο1) Cygni, 61 Cygni, and Albireo (see p.62), which marks the bill of the swan. A pair of binoculars will show the open clusters M29 and M39. Also look out for the magnitude 7.3 open cluster M52, sitting high in the sky in Cassiopeia; the open clusters M36, M37, and M38 in Auriga (see p.46); and M35 in Gemini.
Date
Standard time
Daylight-saving time
October 15
Midnight
1 am
November 1
11 pm
Midnight
November 15
10 pm
11 pm
December 1
9 pm
10 pm
December 15
8 pm
9 pm
Zenith 20°N
ARIES PISCES 40ºN
ANDROMEDA
TAURUS
PERSEUS
Aldebaran
60ºN
PEGASUS CASSIOPEIA
Capella
AURIGA
CEPHEUS ORION
61 Cygni Deneb
Polaris
ο¹ Cygni
Sadr
GEMINI
URSA MINOR
CYGNUS
Castor Pollux
Horizo n 20º N
DRACO
Big Dipper
Procyon
URSA MAJOR
M29 in Cygnus This open cluster can be found sitting against the background star fields of the Milky Way. Located a little way from the star Sadr, it is best observed with a small telescope.
Eclipti c
Albireo
Altair
Vega
Horizon 40ºN
W
ES
BOÖTES
HERCULES
T
CANCER
LEO
EA
ST
0ºN Horizon 6
LOOKING SOUTH The Hyades (see p.23) and Pleiades (see p.38) star clusters in the constellation Taurus make a welcome return to winter skies in the east. A pair of binoculars is all you will need to explore these two open clusters. Both the Pleiades and Hyades are clearly visible to the naked eye, but binoculars will reveal the many glittering stars within them. Other objects of interest to look out for include the Andromeda Galaxy, M31, and the Triangulum Galaxy, M33, sitting high in the sky.
Zenith 60°N
PERSEUS ANDROMEDA
40ºN
ARIES AURIGA
20ºN PEGASUS PISCES
Aldebaran
TAURUS
E cl ipt ic
CETUS
ORION
Betelgeuse
Horizon 60ºN
MONOCEROS
The Orion Nebula Also known as M42, this is one of the finest nebulae in the night sky. A wonderful sight in all types of equipment, a small telescope shows its glowing cavernous gas clouds and embedded stars.
ERIDANUS
Sirius
EA
ST
θ
PHOENIX
AQUARIUS
Fomalhaut
Horizon 40ºN CAPRICORNUS
CANIS MAJOR
Achernar Horizo
GRUS
W n 20ºN
TUCANA
ES
T
N OV E MB E R
NOVEMBER SOUTHERN LATITUDES
STAR MAGNITUDES
-1
0
1
2
3 and above
LOOKING NORTH Look out for the globular cluster M79 lying under the feet of Orion, the Hunter, in the east. This cluster is visible through a small telescope. In the constellation Eridanus, above Orion, you will find an interesting multiple star system, Omicron-2 (ο2) Eridani, with three components, and a double star Theta (θ) Eridani. Both are visible with small telescopes. Deep-sky observers with dark skies will be able to spot the galaxy NGC 1300 in the same constellation using large telescopes.
Zenith 40°S
20ºS ERIDANUS
CETUS
Fomalhaut AQUARIUS
0º
² ο Eridani
Ecliptic
PISCES
TAURUS
Rigel ARIES ORION
PEGASUS
MONOCEROS
Aldebaran Betelgeuse ANDROMEDA
AQUILA
zon Hori
40ºS
CASSIOPEIA
PERSEUS
Capella AURIGA
Horizon 20ºS
GEMINI
Altair
W
ES
T
Hori zon
CYGNUS
Procyon
Deneb
0º
EA
Castor
CEPHEUS
ST
NGC 1300 The barred spiral galaxy NGC 1300 is located about 69 million light-years from Earth. It is particularly faint but can be seen with a very large amateur telescope.
Polaris
LOOKING SOUTH There is a lot to see in the southern skies this month with just the naked eye. Start off by looking for the Large Magellanic Cloud (LMC), west of the constellation Pictor, and the Small Magellanic Cloud (SMC), in Tucana. These are both irregular galaxies close to the Milky Way. The globular cluster 47 Tucanae can be seen with the naked eye as a hazy star very close to the Small Magellanic Cloud. The open clusters NGC 2362 and M41 in Canis Major in the east also make for good small-telescope targets.
Zenith 0°
CETUS
20ºS li Ec c pti
40ºS PHOENIX
ERIDANUS
Fomalhaut Rigel Achernar
AQUARIUS
GRUS
ORION TUCANA CANIS MAJOR
CAPRICORNUS
Canopus PICTOR
OCTANS
PAVO
Sirius CARINA MONOCEROS
PUPPIS
SAGITTARIUS ARA
EA
VELA
ST
α Centauri CENTAURUS
CRUX
β Centauri
SCORPIUS
Hor iz
on 0 º
Horizon 20ºS S 40º zon T Hori ES
W
47 Tucanae This globular cluster in Tucana is a wonderful sight through a small telescope. A large-aperture telescope shows its countless stars packed together in a dense ball.
103
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
ir
ITTA M2 M
CY b
De ne
M 39
CE
A RT
D RA CO
AN 7
S
M52
MED A
HEU
D RO
CEP
M103
MI NOR
SI O P EIA
UR SA
CA S
M31
US 92
LA
GN
UL Al
A
N
M
bi o re
29
57
HE
R LY
A
RC UL
O
R T
ES
2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
NG
C8
69 NG
Polaris
Diffuse nebula
C
88
PE 4
RS
CAM
R PA
M81
ELO
Planetary nebula
DA
LI
S
lla
AM
pe
URS
Ca
A JO
R
N LY
8 M36
X
M3
POINTS OF REFERENCE
M35
LE
O
I
sto
December 1
M
November 15
November 1
October 15
Date
Zeniths
N
O
R
TH
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES
M37
December 15
Horizons 60°N 40°N 20°N
OR
MIN
on
1 am
Ecliptic
Daylight-saving time
Pro cy
Midnight
11 pm
10 pm
9 pm
20°N
EAST
NI
MI ux
GE Po ll
US
EC 1
4
M4
LP 0
STAR MAGNITUDES -1
r
R
N IS
CA
ER
NC
CA
O
LE
ST
A
E
Ca
NO
A RI G AU
HI N M
TIC I V E NA
r
D EL P 13
Mizar
C ANES
pe
VU Ve ga
M
M101
M51
ip
SAG LA
T TE S
Bi
AQU I
H
W
ES
BO Ö
N ORTH
NORTH
LOOK I N G
gD
S EU
4 M3
NOVEMBER | NORTHERN LATITUDES
Alta
104
te Be
OS
M50
CA
Siriu
s
M N IS
A JO
tr ix
CA
EL UM
an ar
DO RA
ad es
DO
Hy
LE
R
M41
PU
S
C
UM OL
BA
SO
U
SUNRISE AND SUNSET ON 15TH NOVEMBER
ST
ge l
d Al
TH
Ri
S
RET
ip ti c
ULU
eb
S
PHO
P I SC E
DA
S OUT H
X
OM E
ENI
A N DR
Achernar
M33
SOUTH
M
LO OK I N G
UM
S
Mira
IES
C E TU
AR
NG
ANA
TO R
T UC
SC UL P
GR
US
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
R UA
IU
S
M15
Zeniths
CI S U S P I S RI N T S AU
aut alh Fom
AQ
P E G A S US
E M2
60°N
SO
U
I
TH
M
30
S
L EU QU U
IA
H O R O LO G I
AX
Ec l
FO R N
US
LUM
DA N
ICU
ERI
RU
NOVEMBER | NORTHERN LATITUDES
EAST 42
EA
use
lge M
M
CR
la
UM
I
CER l Be
OP
O MO N
N OS C
O RI
T
O es)
AQ
UIL
A S 20°N
South
North
STAR MOTION
40°N
W
ad
ES
M1
CA
U TA
PR
M4
NU
lei
P 5(
I CO R
TR
Ecliptic
NO V E M BE R N OR T H E R N L A T IT U DE S 105
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
Alt
A M 2
LA
AQ
UA R
S S
LE
LP HI
S
IU
SU
A ND
R OM ED
NU
US M
A ITT M2
S M2
CY GN
CE PHE US
A
Ec l
ipt
M52
ic
7
9
N
15
O
R T
U Globular cluster
DEEP-SKY OBJECTS Galaxy
M31
CA SSI O PEIA
NGC 86
9
Mira
NGC
M34
A RI E
884
T R I A N G U LU M
C E TU S
M33
M103
N ORTH
NORTH
LOOK I N G
Open cluster
Diffuse nebula
S
S
ELO
SEU
C AM
PER
Planetary nebula
ER
ID
US
IS
) des ia Ple
AL
5(
AN
M4
D PAR
es
RU
ad Hy
U TA
lla pe Ca
20°S
POINTS OF REFERENCE Horizons 0°
S
Rig
el M3
6 8
GA
M3
RI
N LY
X
M42 1
O
37
M
M
N
R
use
Date October 15 November 1 November 15 December 1 December 15
Zeniths
0°
M
35
TH
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
AU
an ar b de Al
40°S
NO
1 am
Midnight
11 pm
10 pm
9 pm
Ecliptic
Daylight-saving time
MO
40°S
EAST
UU P
9
RT A
EG A
CE
M3
Variable star
NI
DE S
D en eb
5
ge tel Be
EQ
S AG
E ST
4
x tri
CE R OS
MI
GE
air
H
W
3
Be
UIL 1
2
NOVEMBER | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
ST
A
E
lla
IO N OR
AQ
106
T EA ST
S
SO
U
BA
CA
R IN A
TO R
opu s
PI C
Can
DO
RA
VOL A
DO
EL UM
AN
NS
ID
T IC
Gacrux
LO G
LO OK I N G
SC
T UC
X
R A
S OUT H
uri ta α Cen
S
ULUM T R I AN G A L E A US T R
AN
NI
au t alh
S
IU I
S
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE
A
40°S
MA
AR
R NO
U ND
LE
SC
OP SC
I
O CR
Zeniths
TE
M
30
M
UA R
AQ O PAV
US
Fo m
GR
0°
C
SO
OR SC
M IU
S
AU
U
TH
CA
TO
UL P
C I R CI N U β Centauri
SOUTH
CENTAURUS
4
P
E HO
OCTANS
NGC 10
AP U S
SMC
Achernar
US
LEO N
Becrux
Acrux
MU SC A
C H AM A E
H YD R
IUM
M E N SA
M
RO
ULU
HO
C RU X
LMC
RE
US
AX
AU P I S C IS S T RI NU S
NOVEMBER | SOUTHERN LATITUDES
H
LA
IS
LU M
PP
VE
PU
CO
CA
ER
RN
M IU OP
FO
S
P
TU
55 M
IU S a Sh
CE
TA
IT
EAST
AG
6
X
ul a
93
OR ST O N R AL A IS
M
PY
IS
M
7
2
2
20°S
40°S
South
North
STAR MOTION
E
M4
ra ha Ad
W
M4
S
OS
C
RI U
ER NOC
NG
6 23
54
S
S NI C A AJO R M M
S NU
MO
PR ICO R
M
50
41
7
M
ST
s iriu 79
M
LEPU 69
M
M2
NGC 1300
Ecliptic
NO V E M BE R S OU T H E R N L A T IT U DE S 107
WEST
108
MO NT H LY S KY GUID ES: OVERVIEW S
DECEMBER As we round off the year, the northern skies contain the spectacular constellations Orion, Taurus, Gemini, and Auriga. These can also be glimpsed from the Southern Hemisphere, along with Vela and Carina.
O RI O N Genitive
Abbreviation
Highest in sky at 10 pm
Beta (β) Orionis, or Rigel, 0.2
Orionis
Ori
December–January 6h
Gemini in the east. The Winter Triangle formed by Betelgeuse, Sirius, and Procyon is easy to locate in the southeast. SIGHTS OF INTEREST Observers in the Northern Hemisphere are spoiled for choice this month. In Orion lies the beautiful nebula M42, which is a superb target for a small telescope or binoculars. In Taurus, the Bull, you can locate two striking star clusters. The Hyades is a large cluster outlining the bull’s face and the Pleiades is possibly the finest open cluster in the sky. Auriga too has several stunning open clusters to look for.
The Geminids If you are observing the Geminids, you might spot a very bright meteor. These “fireballs” add to the excitement of watching these celestial fireworks.
Brightest star
26
Orion, the Hunter, is one of the greatest constellations in the whole night sky. You can find it by spotting the prominent line of three stars that form the hunter’s “belt”, as well as its distinctly colored stars, Rigel and Betelgeuse. Orion also contains one of the most stunning nebulae in the sky, M42, also known as the Orion Nebula.
NORTHERN LATITUDES THE STARS Looking north, the constellations Perseus, Auriga, and Andromeda can be found sitting high in the sky. In the southeast, it is impossible to ignore the magnificent sight of Orion, the Hunter. Orion leads the winter constellations, which include Taurus in the south and
Size ranking
χ2 χ1
GEMINI
5h
U
NGC 2175
ξ
ν
15
ο1
11
ο2 π1 2 π
ORION
λ φ1 φ2 γ
10º
μ Betelgeuse
α
32
ω
MONOCEROS 56 0º
51
δ ε ζ σ
M78 NGC 2024 IC 434
ψ 23 ψ1 ρ 31
CANIS MAJOR
π4
π6π5
22
η M 42
Sirius
π3
Bellatrix
2
29
κ
–10º
METEOR SHOWER The Geminid meteor shower peaks around December 13–14. At its peak you can expect to see around one meteor per minute streaking across the sky from the direction of Gemini.
Aldebaran
TAURUS
69
τ β
ERIDANUS
Rigel
LEPUS
–20º
MIDNIGHT 3 AM
6 AM
Castor
GEMINI
Pollux
9 AM
13 NOON
LEO
Arcturus
Regulus
10°
14
CANCER
11
Betelgeuse
15 Procyon
13
0°
VIRGO
OPHIUCHUS
15 12
–10°
11 –20° 16 17
18 14
18
15 Antares
–30°
–40°
12
16 Spica
17 19
12
POSITIONS OF THE PLANETS
LIBRA
SCORPIUS
15
13
18 17
11
This chart shows the positions of the planets in December from 2011 to 2019. The planets are represented by colored dots, while the number inside each dot denotes the year. For all planets
–50°
except Mercury, the dot indicates the planet’s position on December 15. Mercury is shown when it is at greatest elongation (see p.125). For specific dates, refer to the Almanac.
Mercury
Mars
Saturn
Venus
Jupiter
Uranus
Neptune
EXAMPLES
11
Mars’ position on December 15, 2011
11
Saturn’s position on December 15, 2011. The arrow indicates that the planet is in retrograde motion (see p.125)
DE C E MB E R
109
SOUTHERN LATITUDES Taurus, you have a great opportunity to observe two open star clusters, the Hyades and the Pleiades. The Pleiades star cluster, or M45, can be seen with the naked eye and is a wonderful sight in a small telescope.
Goldfish, and Mensa, the Table Mountain. Look for the Tarantula Nebula, or NGC 2070, in the Large Magellanic Cloud. High in the northeast lies the fantastic nebula M42, in Orion. In the nearby constellation
north. Auriga can be found by locating the bright star Capella, which is low in the sky this month. If you look roughly northeast Gemini is also on show, sitting low in the sky near the horizon. Meanwhile Canis Major, Vela, and Carina can be located in the southeast. December is also a great time to look out for the Magellanic Clouds in the south.
THE STARS The constellations Taurus, Gemini, Orion, and Auriga are visible from the Southern Hemisphere this month. Looking toward the north you can spot the distinct “V” shape of the Hyades star cluster, which marks the head of the constellation Taurus. Just next to it toward the northeast is Orion, a magnificent sight with its bright stars Rigel and Betelgeuse. Emerging from the foot of Orion, Eridanus meanders high across the sky. Look out for Perseus and Auriga below Taurus in the
LEPUS
SIGHTS OF INTEREST The Magellanic Clouds can be seen sitting in the southern part of the night sky this month. The Small Magellanic Cloud sits in Tucana, while the Large Magellanic Cloud hovers on the border of the constellations Dorado, the
Size ranking
Brightest star
Genitive
Abbreviation
Highest in sky at 10 pm
51
Alpha (α) Leporis, or Arneb, 2.6
Leporis
Lep
January
The constellation Lepus, the Hare, sits right under the feet of the magnificent Orion, between Canis Major and Eridanus. Unlike its neighbors, Canis Major and Orion, Lepus contains few bright stars. Even so, it does have a handful of targets to observe. These include M79, a magnitude 8 globular cluster, and a small group of stars catalogued as NGC 2017, both of which can be seen with a small telescope.
The Large Magellanic Cloud You can see the Large Magellanic Cloud with the naked eye. A small telescope reveals the Tarantula Nebula, NGC 2070, embedded within it.
ORION MONOCEROS
Rigel
η
θ Sirius
ζ
17 NGC 2017
ι
λ α
–10º
RX
κ
R
μ
ERIDANUS
Arneb
δ CANIS MAJOR
γ
β
–20º
ε
Nihal M79
LEPUS
Adhara –30º
COLUMBA
6h
5h
CAELUM
9 PM
Capella NEPTUNE 19
18
6 PM
17
16
15
14
13
12
11
Pleiades
TAURUS
AQUARIUS
ARIES
12
3 PM
Aldebaran
Hyades
PISCES
11
10°
Altair
ellatrix
AQUARIUS
0°
Mira 18 Rigel
–10°
CAPRICORNUS 16 14
13 16
12
15 11
E 19
PISCES
18 17 16
15
V
E
13 12
18 16
19
17
14 –30°
Fomalhaut
N
I N
SAGITTARIUS
G S
14
19
–20°
19
Shaula –40°
K
Y
11
–50°
CETUS URANUS
11 0
MONT HLY SKY GUID ES: HIGHLIGHTS
DECEMBER NORTHERN LATITUDES
OBSERVATION TIMES
LOOKING NORTH There are several interesting sights to be seen in the constellation Gemini, the Twins, in the east. Castor, Gemini’s second brightest star, is an interesting multiple star, while the open cluster M35, sitting close to the feet of one of the twins, is a great target for binoculars or a small telescope. Other December treats include the Double Cluster (see p.22) in Perseus; the Andromeda Galaxy (see p.94), which is still high in the sky; and the Milky Way rising up through Cygnus.
Date
Standard time
Daylight-saving time
November 15
Midnight
1 am
December 1
11 pm
Midnight
December 15
10 pm
11 pm
January 1
9 pm
10 pm
January 15
8 pm
9 pm
Zenith 20°N
ARIES TAURUS 40ºN PISCES AURIGA
PERSEUS
GEMINI
Capella
60ºN ANDROMEDA
Castor Pollux Polaris
CEPHEUS
URSA MAJOR
URSA MINOR
PEGASUS
tic Eclip
CASSIOPEIA
CANCER
Deneb Big Dipper DRACO
20ºN izon Hor
Castor A multiple star system, Castor, or Alpha (α) Geminorum, can be seen with a small telescope. The two main stars orbit each other roughly once about every 468 years.
LEO
CYGNUS
Regulus
Horizon 40ºN
W
ES
Hor izon
T
Vega
60º N
BOÖTES
EA
HERCULES
ST
LOOKING SOUTH The Orion Nebula is undoubtedly the prime target in this part of the northern skies (see p.102). It can be found in Orion’s Sword, which drops down from the middle of the “belt” stars. Through a small telescope, you should be able to see the nebula, resembling a celestial cave, with stars embedded in its heart. Larger apertures reveal the nebula’s swirls of gas, which make this one of the finest deep-sky objects in the sky. Also on show are the Hyades and Pleiades—two star clusters in Taurus.
Zenith 60°N
PERSEUS
Capella 40ºN
ANDROMEDA
AURIGA
TAURUS
ARIES 20ºN
GEMINI
Castor Pollux
Aldebaran ORION PEGASUS PISCES
Betelgeuse CANCER
CETUS
Procyon
ti c lip Ec
Rigel
ERIDANUS
MONOCEROS
Sirius HYDRA N 60º izon Hor
Orion The constellation Orion, the Hunter, is a magnificent sight in the winter night sky. The star Betelgeuse marks the shoulder of the Hunter, while Rigel marks his foot.
Horizon 40ºN Hor izon EA 20ºN ST
CANIS MAJOR
AQUARIUS
PUPPIS
PHOENIX
Achernar Canopus
CARINA
Fomalhaut
W
ES
T
DE C E MB E R
DECEMBER SOUTHERN LATITUDES
STAR MAGNITUDES -1
0
1
2
3 and above
LOOKING NORTH The constellation Orion has many interesting objects in and around it to entice observers in the Southern Hemisphere. Sky gazers should look out for the Orion Nebula (see p.102), which is a good target for binoculars or a small telescope. The Pleiades and Hyades star clusters can be enjoyed with the naked eye. Meanwhile, in the nearby constellations Auriga, Monoceros, and Puppis, there are several open clusters to be seen, such as M36, M37, M38, M50, M46, and M47.
Zenith 40°S
20ºS
ERIDANUS CETUS
CANIS MAJOR
Rigel 0º ORION
AQUARIUS
Betelgeuse
Ecliptic
PISCES
Sirius
TAURUS
Aldebaran
ARIES
MONOCEROS PERSEUS
Procyon GEMINI AURIGA
PEGASUS
Capella iz Hor
0 on 4
ºS
Castor
Horizon 20ºS
W
HYDRA
Pollux
ANDROMEDA
CANCER
CASSIOPEIA
ES
T
URSA MAJOR
Horiz on 0º
CEPHEUS
LEO
EA
ST
M38 in Auriga The magnitude 6.4 open cluster M38 is the most scattered of the three famous Messier clusters in Auriga in the north at the moment. It lies 4,200 light-years from Earth.
Polaris
LOOKING SOUTH If you are observing with binoculars, there is a great deal to see looking south. NGC 3114 and NGC 2516 are both prominent open clusters worth observing in Carina in the southeast. The Eta (ε) Carinae Nebula, or NGC 3372, is a bright diffuse nebula visible through binoculars or a small telescope. The bright open cluster IC 2602, or the Southern Pleiades, is a great binocular object. Also look out for the Small Magellanic Cloud in Tucana and the Large Magellanic Cloud, just west of Pictor.
Zenith 0°
20ºS
Rigel CETUS
ORION ERIDANUS 40ºS
CANIS MAJOR
Sirius
PHOENIX
Canopus
AQUARIUS
Achernar PICTOR
Ecliptic
MONOCEROS
PUPPIS
TUCANA
CARINA VELA HYDRA
GRUS
Fomalhaut
OCTANS
º zon 0 Hori
PAVO Horizon 20ºS
EA
ST
Hori z on 4 0ºS
CAPRICORNUS
CENTAURUS
CRUX
SAGITTARIUS
β Centauri α Centauri
ARA
WE
ST
The Large Magellanic Cloud (LMC) A conspicuous naked-eye object, the LMC sits on the border of the constellations Mensa and Dorado. A small telescope will show star clusters and bright patches of nebulosity within it.
111
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
E
Y
S
LY R
AN M M52
C
AS S I OP
NG C 86 9
EU C8 84
lla
PH
I NU B O ÖT E S
CAMELOPARDALIS
Polaris
S
S AG A ITT
C M
M2
DRACO
U RSA MINOR
NG
S M1 03
EIA
4
ED TA 9
EU S
RS
OM ER M3
C EP H
PE
DR LA C
De neb
A
M92
VU
Al
S
LP
bi
EC UL
o re
A
N O
R
29
31
LES
M3
ASU
5
7
T
A
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
M10
M81
1
Big
zar Mi
M51
er Dipp
LY
UR
SV
MA
NE
SA
CA
POINTS OF REFERENCE
R
IC AT
I
CO
A M
BE
Zeniths
January 15
January 1
December 15
December 1
L
N
N
RE
November 15
Date
O
R
M67
TH
11 pm
10 pm
9 pm
8 pm
60°N
40°N
Midnight
Standard time
OBSERVATION TIMES
EN
JO
Pollux
Horizons 60°N 40°N 20°N
Ecliptic
Daylight-saving time
1 am
Midnight
11 pm
10 pm
9 pm
20°N
EAST
M1
57
GN U
M
a
Ve g
RC U
or
Cast
PE G
DEL 2
lus
Reg u
US 1
O
U LE
H
W ST HE
M13
pe
N ORTH
NORTH
LOOK I N G
Ca
DECEMBER | NORTHERN LATITUDES 0
STAR MAGNITUDES -1
M44
IN
LE
ST
ES
OR
A
E
M
C ER
CA N EO
IC
NI G E MI X
N
A
IG
AU R
EQ U
112
S
CER
HYDRA
EAST
M 46 M 93
PU PP
I
EA ST
Ad ha ra
50
H
M
SO
U
M 41
CA
Sir
S
NI
RO
ius
CE
OR
AJO
R
s
BA
opu
Can
CO LU M
SM
e
us
lge
te
Be
P IC
TOR
rix
A DO
S
G IU M
S OUT H
HOROLO
S
X
ira M
NG TRIA
FO R N A
A RIE
E R I DA N U S
SOUTH
R E T I C U LU M
TAUR U
M45 (Pleiades)
P E RS E U S
LO OK I N G
M
des
Hya
C A E LU
D OR
lat
N
Bel
IO
Rigel
US
2
LE P
M4
OR
ra n
ba
de
Al
GA
TU
S
r erna Ach
CE
PI
AN
S
D
R
M33
UM UL
C
ES O PH
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
IX
Horizons 60°N 40°N 20°N
POINTS OF REFERENCE
EN
Zeniths
SC
Ec l ipt ic
U
SO
OR
60°N
T LP
U
US
AS PE G
A
ED OM
DECEMBER | NORTHERN LATITUDES
8
O
T
n 47
yo M
oc Pr
TH
AQ
M ON
E
S
IU
M4
UA R
S IN 40°N
20°N
South
North
STAR MOTION
W
I
ST
CAN NI M
t
M35
au
CA IN alh
M37
Fo m
G EM 1
CI S
M
P IS
M36
S IN U
AU
Ecliptic
TR
M38
AU S
RI
D E C E M BE R N OR T H E R N L A T IT U DE S 113
WEST
MO NT H LY S KY GUID ES: SKY GUID ES
WEST
UA R IU
T
A
ND
RO M ED
A M3 1
PI
SC
ES
M3 3
SU TR
G
tic
M34
ira
S LA
CE NGC 8
869
M45 (Pleiades)
TAURUS
E R I DA N U S
84
OR
IO
M3
8
lla Be
x tri
N
l
AU R
M3
IGA
lla Cape
ran
eba
Ald
des
Hya
CAMELOPARDALIS
N
A RT
O
R
N ORTH
NORTH
LOOK I N G
NGC
PER SE US
I ES
E cli p
AR U LU M
M103
P EI A
IAN
M
C
AS S IO
S
GA M5 2
US
TU
PE
H
W
ES C EP HE
CE
S
T
1
2
3
4
5
Variable star
Globular cluster
DEEP-SKY OBJECTS Galaxy
Open cluster
Diffuse nebula
Planetary nebula
6
M1
5
7
M3
M3
LYN
X
e
20°S
POINTS OF REFERENCE Horizons 0°
40°S
M50
GE
MI
SA
NI
or
OR
st
AJ
Ca
M
on x
O
llu Po
N
R
OR Date November 15 December 1
0°
TH
M48
20°S
8 pm
9 pm
10 pm
11 pm
Midnight
Standard time
OBSERVATION TIMES
UR
Pro cy
December 15 January 1 January 15
Zeniths
A
DR
HY
1 am
Midnight
11 pm
10 pm
9 pm
40°S
Ecliptic
Daylight-saving time
67
M
OS ER OC
ON
M
us ge
42 M
S
PU
LE
DECEMBER | SOUTHERN LATITUDES 0
STAR MAGNITUDES -1
EAST
ER
M4
4
NC
CA
ST
EA
Be
tel
IN
SM NI CA
ge Ri
AQ
114
IA
TH
P
ST
IS
7
6
SO
U
VE
LA
PP
CE NT AU
rux
NGC 3114
Gac
IS
3372
RU
S
C RU
X
ux
Becr
Acr ux
IC 2602
NGC
516
EO N
A
C I RC I N U S
MA E L
ME N S
LMC SMC
RU
S
S OUT H
SOUTH
M
HYD
GIU
ar ern Ach
OCTANS
OLO
TRIANGULUM AU S TR AL E
LO OK I N G
α Centauri
HOR
AP US
RETICULUM
β Centauri
CA
C HA
M
DO
E LU
RA
CA
DO
A NS
MU S
VOL
OR
pu s
Ca no
BA
NA PI C T
C2
RI
NG
CA
M
US
NG
FO RN A X
C 10
OE
A RA
A NA
N
TUC
PAVO
4
PH
IX
T
EL E
-1
0
1
STAR MAGNITUDES
2
3
4
5
Variable star
Galaxy
Globular cluster
DEEP-SKY OBJECTS Open cluster
Diffuse nebula
Planetary nebula
Horizons 0°
20°S
POINTS OF REFERENCE
OP SC
M
Fo m
alh
au
Zeniths
IU
US
US
I ND
GR
40°S
DECEMBER | SOUTHERN LATITUDES
EA
YX
PU
AN
S
TU CE SC
R
TO
ID
IC
R
0°
M
SO
U
TH
OS CO P
I
UM
UL P
AQ
IUS UA R
S
A U P I SC S TR IS IN U GI
EAST
SA
RA
T
HYD
TL
S
0
20°S
40°S
South
North
STAR MOTION
ES
AN
W
ra ha Ad
M3
us M41
LU
PR
Siri
CO
CA
M4
M R
S
M4
IS
O AJ IU
CAN
S
TT AR
PU
NU
LE
I CO R
ER
Ecliptic
D E C E M BE R S OU T H E R N L A T IT U DE S 115
WEST
t
116
A LM ANAC
ALMANAC This section contains astronomical calendars listing major celestial events for the years 2011–2019. These calendars show the phases of the Moon, eclipses of the Sun and the Moon, and motions of the planets. The latter include the greatest western and eastern elongations (the angle between the Sun and a planet) of Mercury and Venus. Also shown are the oppositions of Mars, Jupiter, and Saturn, when these planets are on the opposite side of Earth from the Sun and visible in the sky through the night. KEY
Full Moon
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Total eclipse of the Moon
New Moon
MARCH
APRIL
Partial eclipse of the Moon
MAY
JUNE
JULY
Partial eclipse of the Sun
AUGUST
SEPTEMBER
2011 This year sees an unusually large number of eclipses—four partial solar eclipses and two total lunar eclipses. Other highlights include a close conjunction of Jupiter and Uranus, which began in 2010 and continues through January 2011. A conjunction is a close alignment of two bodies in the sky and occurs when both planets lie in the same line of sight as viewed from Earth. Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
July 1 April 4 Saturn at opposition, magnitude 0.4
January 4 Partial eclipse of the Sun visible from North Africa, eastern Europe, Saudi Arabia, and western Asia
September 3
December 10
Mercury at greatest morning elongation
Total eclipse of the Moon visible from Asia, Australasia, and northwest North America
June 1
January 8 Venus at greatest morning elongation
Partial eclipse of the Sun visible from the south Indian Ocean
May 7
Partial eclipse of the Sun visible from the Arctic, northeast Asia, and northern Canada
Mercury at greatest morning elongation
January 9 Mercury at greatest morning elongation November 14 Mercury at greatest evening elongation June 15 Total eclipse of the Moon visible from Australia, Asia, Africa, and Europe
December 23 July 20
October 29
Mercury at greatest evening elongation
Jupiter at opposition, magnitude -2.9
Mercury at greatest morning elongation
March 23 Mercury at greatest evening elongation November 25 Partial eclipse of the Sun visible from Antarctica
2011–2012
KEY
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Total eclipse of the Moon
New Moon
Full Moon
FEBRUARY
MARCH
APRIL
Partial eclipse of the Moon
MAY
JUNE
Partial eclipse of the Sun
JULY
AUGUST
SEPTEMBER
March 3
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
December 3
Mars at opposition, magnitude -1.2
March 5
Jupiter at opposition, magnitude -2.8
Mercury at greatest evening elongation
July 1 Mercury at greatest evening elongation December 4 Mercury at greatest morning elongation
June 4
June 5–6
Partial eclipse of the Moon visible from western regions of North and South America, Pacific Ocean, Australasia, and east Asia
Transit of Venus visible from east Asia, Australasia, and northwestern North America
April 15 Saturn at opposition, magnitude 0.2
August 15 Venus at greatest morning elongation
April 18 Mercury at greatest morning elongation
November 13–14
August 16 Mercury at greatest morning elongation
Total eclipse of the Sun visible from south Pacific Ocean. Partial eclipse visible from eastern Australia and New Zealand
May 20–21
March 27 Venus at greatest evening elongation
2012 In addition to a partial eclipse of the Moon, this year sees a total and an annular eclipse of the Sun. However, the highlight of 2012 is the rare transit of Venus. The next such event will not occur until the year 2117. Transit of Venus On June 5–6 Venus will pass across the face of the Sun in a rare transit event that reveals Earth’s neighboring planet in silhouette.
Annular eclipse of the Sun visible from Japan and north Pacific Ocean. Partial eclipse visible from east Asia and western North America
October 26 Mercury at greatest evening elongation
Annular eclipse In May the Moon will lie near its farthest point from Earth as it eclipses the Sun. Even when perfectly aligned, a thin ring of sunlight will remain visible.
117
118
A LM ANAC
2013 Two annular eclipses of the Sun are visible this year, of which one appears total from some locations. A partial lunar eclipse is widely visible, and there is a rare conjunction of the inferior planets Mercury and Venus. Widespread eclipse Partial eclipses of the Sun can be seen over wider areas than total eclipses. The November 2013 eclipse will be visible from many regions. KEY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Total eclipse of the Moon
New Moon
Full Moon
JANUARY
Mercury and Venus In June Mercury and Venus will make a rare close approach in evening skies, tracing paths similar to those seen in this time-lapse image.
MARCH
APRIL
Partial eclipse of the Moon
MAY
JUNE
Partial eclipse of the Sun
JULY
AUGUST
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
November 1 Venus at greatest evening elongation
May 9–10 Annular eclipse of the Sun visible from northeastern Australia and south Pacific Ocean. Partial eclipse visible from eastern Australia, northern New Zealand, and Hawaii
November 3
October 9 Mercury at greatest evening elongation
Annular-total eclipse of the Sun visible from north Atlantic Ocean and central Africa. Partial eclipse visible from northeastern South America, southern Europe, and Africa
June 12 Mercury at greatest evening elongation
February 16 Mercury at greatest evening elongation
April 25 Partial eclipse of the Moon visible from Europe, Africa, Asia, and Australia
November 18 Mercury at greatest morning elongation
July 30 April 28 March 31 Mercury at greatest morning elongation
Saturn at opposition, magnitude 0.1
Mercury at greatest morning elongation
2013–2014
KEY
Full Moon
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Total eclipse of the Moon
New Moon
FEBRUARY
MARCH
APRIL
MAY
Partial eclipse of the Moon
JUNE
JULY
Partial eclipse of the Sun
AUGUST
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
November 1
January 5
April 8
Jupiter at opposition, magnitude -2.7
Mars at opposition, magnitude -1.5
Mercury at greatest morning elongation
May 10 Saturn at opposition, magnitude 0.1
March 14
October 8
Mercury at greatest morning elongation
Total eclipse of the Moon visible from North America, Australasia, and east Asia
12 July Mercury at greatest morning elongation April 15
September 21
Total eclipse of the Moon visible from North America, South America, and New Zealand
Mercury at greatest evening elongation
March 22 Venus at greatest morning elongation May 25 Mercury at greatest evening elongation April 29 Partial eclipse of the Sun visible from west Australia January 31 Mercury at greatest evening elongation
2014 In addition to a pair of partial solar eclipses and two total lunar eclipses, this year sees rare celestial events such as a brief occultation (see p.125) of a bright star by an asteroid and occultations of Saturn by the Moon. Occultation in Leo On March 20, 2014 Leo’s brightest star Regulus (bottom right) vanishes briefly from North American skies as the asteroid 163 Erigone passes in front of it.
October 28 Partial eclipse of the Sun visible from western North America
The Moon and Saturn Between March and May 2014 the Moon will pass in front of the ringed planet Saturn no fewer than three times.
119
120
A LM ANAC
2015 This year sees two eclipses of the Sun, one of which is partial and the other total (though only from Arctic northern latitudes). There is also a more widely visible pair of total lunar eclipses, one in spring and one in fall. Lunar eclipse When the full Moon passes into Earth’s shadow on September 28, the eclipse will be widely visible on either side of the Atlantic Ocean. KEY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Total eclipse of the Moon
New Moon
Full Moon
JANUARY
Venus at its best Our nearest planetary neighbor, Venus, will be a prominent evening “star” in mid-2015 and an equally brilliant morning object later in the year.
MARCH
APRIL
MAY
Partial eclipse of the Moon
JUNE
JULY
Partial eclipse of the Sun
AUGUST
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
June 6 Venus at greatest evening elongation April 4 February 6 Jupiter at opposition, magnitude -2.6
Total eclipse of the Moon visible from western North America, Australasia, and east Asia
September 4 Mercury at greatest evening elongation
May 7 Mercury at greatest evening elongation
January 14 Mercury at greatest evening elongation
October 16 Mercury at greatest morning elongation
September 13 Partial eclipse of the Sun visible from southeast Africa and Antarctica
June 24 Mercury at greatest morning elongation March 20 Total eclipse of the Sun visible from the Arctic. Partial eclipse of the Sun visible from Europe, North Africa, and northwest Asia February 24 Mercury at greatest morning elongation
December 29 September 28 Total eclipse of the Moon visible from Europe, Africa, North America, and South America
Mercury at greatest evening elongation
May 23 Saturn at opposition, magnitude 0.0 October 26 Venus at greatest morning elongation
2015–2016
KEY
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
Total eclipse of the Moon
New Moon
Full Moon
FEBRUARY
MARCH
APRIL
Partial eclipse of the Moon
MAY
JUNE
JULY
Partial eclipse of the Sun
AUGUST
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
June 3 February 7 Mercury at greatest morning elongation
Saturn at opposition, magnitude -0.3
September 1
June 5
Annular eclipse of the Sun visible from Atlantic Ocean, Central Africa, Madagascar, and Indian Ocean. Partial eclipse of the Sun visible from Africa and Indian Ocean
Mercury at greatest morning elongation December 11 March 9
March 8
Total eclipse of the Sun visible from Sumatra, Borneo, and Sulawesi in Indonesia and Pacific Ocean. Partial eclipse of the Sun visible from east Asia, Australia, and Pacific Ocean
Jupiter at opposition, magnitude -2.5
Mercury at greatest evening elongation May 9 Transit of Mercury visible from North America, South America, Europe, Africa, and Central Asia
April 18 August 16
Mercury at greatest evening elongation
2016 Along with two eclipses of the Sun, this year’s most interesting astronomical highlight is a transit of Mercury. A similar event will take place in November 2019— the last transit event until 2032. Planetary conjunction The bright planets Jupiter (right) and Saturn (left) are close to each other throughout the year. In January and August Venus joins them to make a rare “triple conjunction.”
Mercury at greatest evening elongation
May 22
September 28
Mars at opposition, magnitude -2.1
Mercury at greatest morning elongation
Transit of Mercury On May 9, 2016 the innermost planet Mercury will speed across the face of the Sun in a rare “transit” alignment.
121
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A LM ANAC
2017 This year sees both total and annular eclipses of the Sun, as well as a widely visible partial lunar eclipse. Another interesting celestial event is an exceptionally close conjunction of Venus and Jupiter during November. Total solar eclipse A spectacular total eclipse will be visible across the USA on August 21, 2017. It will last for more than two minutes in many places. KEY
Full Moon
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Saturn’s open rings Due to the changing alignment of the planets, Saturn’s brilliant rings will appear “wide open” when seen from Earth throughout 2017. Total eclipse of the Moon
New Moon
MARCH
APRIL
Partial eclipse of the Moon
MAY
JUNE
JULY
Partial eclipse of the Sun
AUGUST
April 1
June 3
Mercury at greatest evening elongation
Venus at greatest morning elongation
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
April 7 Jupiter at opposition, magnitude -2.5
January 12
August 7
Venus at greatest evening elongation
Partial eclipse of the Moon visible from North America, South America, Europe, Africa, and Asia June 15 Saturn at opposition, magnitude -0.3 September 12
January 19
Mercury at greatest morning elongation
Mercury at greatest morning elongation May 17 Mercury at greatest morning elongation February 26 Annular eclipse of the Sun visible from Pacific Ocean, Chile, Argentina, Atlantic Ocean, and Africa. Partial eclipse of the Sun visible from southern South America, Atlantic Ocean, Africa, and Antarctica August 21
Total eclipse of the Sun visible from North Pacific, the USA, and South Atlantic. Partial eclipse of the Sun visible from North America and northern South America July 30 Mercury at greatest evening elongation
November 23 Mercury at greatest evening elongation
2017–2018
KEY
Full Moon
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Total eclipse of the Moon
New Moon
MARCH
APRIL
MAY
Partial eclipse of the Moon
JUNE
JULY
Partial eclipse of the Sun
AUGUST
SEPTEMBER
Annular eclipse of the Sun
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
November 6 Mercury at greatest evening elongation January 1
May 9
August 11
Mercury at greatest morning elongation
Jupiter at opposition, magnitude -2.5
Partial eclipse of the Sun visible from northern Europe and northeast Asia
July 12 Mercury at greatest evening elongation
March 15 Mercury at greatest evening elongation August 17 Venus at greatest evening elongation
December 15
July 13
Mercury at greatest morning elongation
Partial eclipse of the Sun visible from southern Australia
February 15 Partial eclipse of the Sun visible from Antarctica and southern South America
August 26 Mercury at greatest morning elongation June 27 Saturn at opposition, magnitude -0.3 April 29
January 31 Total eclipse of the Moon visible from Europe, Africa, Asia, and Australia
2018 None of this year’s three solar eclipses are total. However, there is a total lunar eclipse in July, an exceptionally close approach of Mars to Earth around the same time, and a close conjunction of Mars and Jupiter in early January. Blue moons January and March 2018 will both see rare “blue moons”—events where two full moons occur in the same calendar month.
Mercury at greatest morning elongation
July 27 Mars at opposition, magnitude -2.8 Total eclipse of the Moon visible from Asia, Australia, Pacific Ocean, and western North America
Close approach of Mars In July 2018 Mars will come within 36 million miles (58 million km) of Earth, making it exceptionally bright and large in our skies.
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A LM ANAC
2019 This year sees total, annular, and partial eclipses of the Sun, as well as partial and total eclipses of the Moon. Other highlights include a rare transit of Mercury and an unusual disappearing act by Jupiter’s satellites. Saturn’s great white spot During 2019 Saturn reaches its northern midsummer, when enormous “white spot” storms appear, such as this one seen in 1994. KEY
Full Moon
JANUARY
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
FEBRUARY
Lonely Jupiter On November 9, 2019 Jupiter briefly appears moonless, with all four of its bright satellites simultaneously hidden behind the giant planet. Total eclipse of the Moon
New Moon
MARCH
APRIL
MAY
Partial eclipse of the Moon
JUNE
JULY
Partial eclipse of the Sun
AUGUST
Annular eclipse of the Sun
SEPTEMBER
OCTOBER
Total eclipse of the Sun
NOVEMBER
DECEMBER
July 2 Total eclipse of the Sun visible from south Pacific, Chile, and Argentina. Partial eclipse of the Sun visible from south Pacific and South America July 9 Saturn at opposition, magnitude -0.3 June 10
January 6
November 11
Jupiter at opposition, magnitude -2.6
Venus at greatest morning elongation Partial eclipse of the Sun visible from northeast Asia and north Pacific
August 9
Transit of Mercury visible from North America, South America, Europe, Africa, and central Asia
Mercury at greatest morning elongation
April 11 Mercury at greatest morning elongation
October 20 Mercury at greatest evening elongation
July 16
December 26
Partial eclipse of the Moon visible from North America, South America, central Pacific, Europe, and Africa
Annular eclipse of the Sun visible from Saudi Arabia, India, Sumatra, and Borneo. Partial eclipse visible from Asia and Australia
January 21 Total eclipse of the Moon visible from South America, Europe, Africa, Asia, and Australia
November 28 June 23 Mercury at greatest evening elongation
February 27 Mercury at greatest evening elongation
Mercury at greatest morning elongation
G L OS S A R Y
GLOSSARY Aperture The diameter of the main mirror or lens in a telescope or binoculars. A large-aperture telescope can collect more light and detect fainter objects than a smallaperture telescope. Asterism A recognizable pattern of stars, where the stars are either a part of a constellation or are members of several constellations. An example is the Big Dipper in Ursa Major. Astrophotography The photography of celestial objects in the night sky, including photography of the Sun and of eclipses.
Deep-sky object Any celestial object lying beyond the Solar System, excluding stars.
Local group A small cluster of over 30 galaxies; it includes our own galaxy, the Milky Way.
Planetary nebula A glowing shell of dust and gas ejected by a dying star that appears as a luminous planet.
Double star Two stars not physically associated with each other, but appearing close together when viewed from Earth.
Magnitude The brightness of a celestial object, measured on a numerical scale, where brighter objects are given small or negative numbers, and fainter objects are given larger numbers.
Radiant The point in the sky from which the tracks of meteors that are members of a particular meteor shower appear to originate.
Eclipse An alignment of a planet or moon with the Sun, which casts a shadow on another celestial body. During a lunar eclipse the Earth’s shadow is cast on the Moon, and during a solar eclipse, the Moon’s shadow is cast on Earth. Ecliptic The plane of Earth’s orbit
Binary star Two stars in a mutual orbit around a common center of mass and bound together gravitationally. Celestial equator The celestial equivalent of Earth’s equator. The celestial equator marks a line where the plane of Earth’s equator meets the celestial sphere. Celestial poles The two points at which the line of Earth’s axis, extended outward, meets the celestial sphere and around which the stars appear to revolve. Celestial sphere The imaginary sphere that surrounds Earth, and upon which all celestial objects appear to lie. Conjunction An alignment of objects in the night sky, with one passing in front of the other, particularly when a planet lines up with the Sun as viewed from Earth. Constellation A named area of stars or a designated area of sky around a star pattern. There are currently 88 officially recognized constellations. Declination A coordinate used in
the equatorial coordinate system; it is the celestial equivalent of latitude on Earth. It is measured in degrees above or below the celestial equator, which has a declination of 0º.
around the Sun, or the projection of that plane onto the celestial sphere. Elliptical galaxy A galaxy that appears as an ellipse. These contain very little gas and dust and are usually devoid of star formations. Elongation The angular separation between the Sun and an inferior planet as viewed from Earth. Also used at the time of maximum angular separation (greatest elongation) between the inner planets, Mercury or Venus, and the Sun. Equinox The time when the Sun is vertically overhead Earth’s equator, and days and nights are of equal length. Galaxy A huge mass of stars, gas, and dust linked by gravity. Galaxies may vary from thousands to hundreds of thousands of light-years in range. Globular cluster A sphere of thousands of stars linked by gravity. Inferior planets Planets whose orbit
around the Sun falls inside Earth’s orbit. The two inferior planets are Mercury and Venus. Light-year The distance traveled by light in one year— 5,878 billion miles (9,460 billion km).
Meteor shower A substantial number of meteors that appear to originate from a common point in the sky. Multiple stars A system of stars that are bound together gravitationally and are in mutual orbits. Multiple stars have at least three stars and may contain up to a dozen stars.
Retrograde motion The rotation of a planet or moon in the opposite direction to its orbit. All the planets orbit the Sun in the direction of the Sun’s rotation: counterclockwise when viewed from above the Sun’s north pole. Most planets also rotate (spin) counterclockwise. Venus and Uranus have retrograde motion: clockwise compared with their counterclockwise orbits.
Nebula A cloud of dust and gas in space, usually made visible by the light of the neighboring stars.
Right ascension (RA) The celestial equivalent of longitude on Earth. It is measured in hours from the position where the ecliptic intersects the celestial equator in spring.
Open cluster A loose group of up to a few hundred stars, bound by gravity and found in the arms of a galaxy.
Solar system The family of eight recognized planets and several other celestial bodies such as moons that orbit the Sun.
Occultation The passage of one celestial body of a larger apparent size over another body of a smaller apparent size, which results in the more distant body being entirely or partially hidden. For example, when the Moon passes over a distant star, it hides the star from our view.
Spiral galaxy A galaxy that has a distinct set of spiral arms composed of bright young stars. Spiral galaxies are rich in gas and dust, and offer prime conditions for star formation.
Opposition The time when an outer planet lies on the exact opposite side of Earth from the Sun. The planet is at its closest to Earth and therefore appears brightest at this time. Orbit The path followed by a planet or other celestial body around the Sun, or by a moon around its parent planet. Planet A celestial body that has cleared away any planetary debris from its orbit around the Sun and is of a roughly round shape due to its own gravity.
Star A huge sphere of glowing plasma that emits heat and light by means of nuclear reactions at its center. Superior planets Planets whose orbit around the Sun are outside the orbit of Earth. Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto are the superior planets. Variable star A star whose magnitude varies over time, brought about by intrinsic or extrinsic changes, such as being eclipsed by another star. Zodiac A band on either side of the ecliptic, through which the Sun, Moon, and planets appear to travel.
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I NDEX
INDEX Note: Months occurring as subentries are arranged in month order. 16-17 Draconis 86 47 Tucanae 85, 87, 93, 101, 103
A Achernar 93, 101 Acrux 47, 53 Albireo 62, 76, 102 Alcor 52, 70 Aldebaran 100 Algieba 38 Almach 95 almanac 116–24 Alpha Centauri 53 Alpha Librae 71 Alphard 36, 37 Altair 70, 93 Andromeda Galaxy 8–9, 84, 86, 92–5, 100–2, 110 angular distances 11 annular eclipses 117–18 Antares 60, 61 April skies 44–51 Aquarid meteor showers 52–3, 69 Aquarius 85, 87, 93 Arcturus 36, 44, 52, 62, 68 Aries 94–5 astrophotography 15 August skies 76–83 Auriga 20–3, 30, 46, 94, 108–9, 111 Auroras 7, 15
Carina 21, 23, 37, 109, 111 IC 2602 cluster 31, 37, 45, 111 NGC 2516 cluster 55, 111 Carina Nebula 37, 39, 45, 111 Cassiopeia 84, 92, 94, 100, 102 Castor 23, 28–9, 110 Cat’s Eye Nebula 54 celestial sphere 7, 10–11, 18–19 Centaurus 21, 29, 37, 45, 53, 77 Omega Centauri 39, 45, 53, 61, 63 Cepheus 84 Cetus 85, 101 Circlet asterism 92, 93 Coalsack Nebula 31, 45, 55, 61 Coathanger asterism 86 Coma Berenices 38, 44, 52 conjunctions of planets 116, 118, 121–3 constellation movements 12 coordinate system 10–11 Crab Nebula 30, 100 Crux 29, 37, 45, 47, 53, 69 Coalsack Nebula 31, 45, 55, 61 NGC 4755 cluster 39, 45 Cygnus 62, 70, 76, 79, 84, 102 Cygnus Rift 76
D
Beehive Cluster 28, 31, 36 Beta Capricorni 79 Beta Centauri 53 Betelgeuse 21–2, 101, 108–9, 110 Big Dipper 36, 44, 52 binoculars 14 “blue moons” 123 Bode’s Galaxy (M81) 36, 44, 46, 70 Boötes 36, 44, 52, 62, 68 Brocchi’s Cluster 86
daily movements 12 December skies 12, 108–15 declination 10, 11 deep-sky objects 19 Delta Aquarid meteor shower 69 Delta Cephei 84 Deneb 70, 76 digital cameras 15 Diphda 101 distance measurements 9, 11 Dobsonian reflector 15 Dorado 93, 101, 109 Double Cluster 22, 78, 92, 94, 100, 110 “Double-Double” star system 70, 86 Draco 60, 68, 86 Dumbbell Nebula 77–8
C
E
Camelopardalis 30 cameras 15 Cancer 28, 31, 36 Canes Venatici 46 Canis Major 21, 36, 101, 103, 109 Canopus 21, 29, 37 Capella 20, 21–2, 109 Capricornus 77, 79, 84
Eagle Nebula 69, 71 Earth celestial sphere 10–11 changing sky 12–13 Moon and Earth 8 eclipses 13, 116–24 elongations of planets 21, 116–24 Enif 84, 86–7
B
Epsilon Lyrae (“DoubleDouble” star system) 70, 86 equator celestial sphere 10, 11 movement at equator 12 Eridanus 85, 93, 101, 103, 109 Eta Aquarid meteor shower 52–3
F False Cross 29, 37 February skies 28–35 flashlights 14 Fomalhaut 77, 85, 93
G galactic hub 69 galaxies 8–9 see also stars Gamma Arietis 94 Gamma Equulei 86 Gemini 22, 28–9, 102, 108–10 Geminid meteor shower 108 Great Bear see Ursa Major Great Square of Pegasus 84, 92
H Hadar 69, 77 Helix Nebula 85, 87 Hercules 54, 60, 62–3, 68 highlights pages, using the sky guides 18 horizons 19 Hyades 23, 38, 94, 100–2, 108–11 Hydra 44, 46 Alphard 36, 37 M83 spiral galaxy 47, 53, 61 Hydrus 93, 101
I IC 2602 (Southern Pleiades) 31, 37, 45, 111 IC 4665 star cluster 63, 68 inferior planets 13, 116–24 see also Mercury; Venus inner planets, locating 18
J January skies 20–7 Jewel Box (M83 spiral galaxy) 39, 45, 47, 53, 61 July skies 68–75 June skies 12, 60–7 Jupiter conjunctions 116, 121–3 oppositions 116–24 satellites 124
K Kemble’s Cascade 30
L Lagoon Nebula 63, 69, 71, 77, 85 Large Magellanic Cloud (LMC) 21, 93, 95, 101, 103, 109, 111 latitude lines, finding latitude lines 19 Leo 28–9, 31, 37–8, 44, 47 occultations 119 Sickle of 36, 44 Leonid meteor shower 17, 100 Lepus 109 Libra 69, 71 light-years 9 Little Bear (Ursa Minor) 22, 60 LMC see Large Magellanic Cloud Local Group 8–9 lunar eclipses 13, 116–24 Lupus 61, 77 Lyra 68, 70, 76, 86, 92 Lyrid meteor shower 44
M M1 (Crab Nebula) 30, 100 M2 star cluster 85, 87 M3 star cluster 46 M4 star cluster 87 M5 star cluster 60, 68, 71 M6-7 star clusters 61–2, 69, 77, 85, 87 M8 (Lagoon Nebula) 63, 69, 71, 77, 85 M10 star cluster 54, 68 M11 (Wild Duck Cluster) 76 M12 star cluster 54–5, 68 M13 star cluster 54, 60, 62–3, 68, 78 M15 star cluster 84, 85, 87 M16 star cluster 69, 71 M17 (Omega Nebula) 79 M20 (Trifid Nebula) 69, 77, 79 M22 star cluster 63, 69, 71, 85, 87 M23 star cluster 79 M24 star cluster 69, 77, 79 M27 (Dumbbell Nebula) 77–8 M29 star cluster 79, 102 M30 star cluster 79 M31 (Andromeda Galaxy) 8–9, 84, 86, 92–5, 100–2, 110 M33 (Triangulum Galaxy) 93–5, 100–2 M34 star cluster 92 M35 star cluster 22, 28, 102, 110 M36-38 star clusters 30, 46, 94, 102, 111 M39 star cluster 62, 79, 84, 102 M41 star cluster 21, 30, 103
M42 (Orion Nebula) 20–2, 102, 108–11 M44 (Beehive Cluster) 28, 31, 36 M45 (Pleiades) 37–8, 45, 94, 100–2, 108–11 M47 star cluster 23, 29 M48 star cluster 46 M51 (Whirlpool Galaxy) 52, 60 M52 star cluster 92, 94, 102 M57 (Ring Nebula) 68, 77–8 M61 spiral galaxy 39 M66 spiral galaxy 47 M77 spiral galaxy 101 M79 star cluster 103, 109 M81 (Bode’s Galaxy) 36, 44, 46, 70 M83 (Jewel Box) 39, 45, 47, 53, 61 M92 star cluster 63, 78 M95-96 star clusters 47 M104 (Sombrero Galaxy) 39 M105 star cluster 47 Magellanic Clouds see Large Magellanic Cloud; Small Magellanic Cloud magnitude of stars 19 March skies 36–43 Mars close approach 123 conjunctions 123 oppositions 116–24 May skies 52–9 measuring distance 9, 11 size 11 Melotte 111 38, 52 Mensa 93, 101, 109 Mercury close approach 118 conjunctions 118 elongations 21, 116–24 naked-eye observations 13 Transit of 121, 124 Messier clusters see M36-38 star clusters meteor showers January skies 20 April skies 44 May skies 52–3 July skies 69 August skies 76 October skies 92 November skies 17, 100 December skies 108 Milky Way 8 January skies 20–1 February skies 28–9, 31 April skies 45, 47 May skies 55 June skies 61 July skies 69 August skies 78 December skies 110 Mira 101
IN DE X
Mizar 52, 70 Monoceros 28, 30 monthly sky guides 16–19 January 20–7 February 28–35 March 36–43 April 44–51 May 52–9 June 12, 60–7 July 68–75 August 76–83 September 84–91 October 92–9 November 100–7 December 12, 108–15 Moon “blue moons” 123 Earth and Moon 8 eclipses 13, 116–24 phases 116–24 movement of objects 12–13, 19, 116–24
N naked-eye observations 13, 15 Neptune 18 January skies 21 February skies 29 March skies 36 April skies 44 May skies 52 June skies 60 July skies 68 August skies 76 September skies 85 October skies 93 November skies 101 December skies 109 Newtonian reflector 15 NGC 104 star cluster (47 Tucanae) 85, 87, 93, 101, 103 NGC 188 star cluster 46 NGC 457 star cluster 100 NGC 663 star cluster 100 NGC 752 star cluster 95 NGC 869/884 (Double Cluster) 22, 78, 92, 94, 100, 110 NGC 1300 spiral galaxy 103 NGC 2017 star cluster 109 NGC 2070 (Tarantula Nebula) 21, 101, 109 NGC 2244 star cluster 28, 30 NGC 2516 star cluster 55, 111 NGC 2547 star cluster 23 NGC 3114 star cluster 111 NGC 3132 star cluster 23 NGC 3372 (Carina Nebula) 37, 39, 45, 111 NGC 4755 see Jewel Box NGC 5139 (Omega Centauri) 39, 45, 53, 61, 63 NGC 6231 star cluster 61 NGC 6530 star cluster 69
NGC 6543 (Cat’s Eye Nebula) 54 NGC 6633 star cluster 55 NGC 7000 (North America Nebula) 15, 70, 84 NGC 7293 (Helix Nebula) 85, 87 noctilucent clouds 68 North America Nebula 15, 70, 84 Northern Cross see Cygnus northern latitudes January 20, 22, 24–5 February 28, 30, 32–3 March 36, 38, 40–1 April 44, 46, 48–9 May 52, 54, 56–7 June 60, 62, 64–5 July 68, 70, 72–3 August 76, 78, 80–1 September 84, 86, 88–9 October 92, 94, 96–7 November 100, 102, 104–5 December 108, 110, 112–13 November skies 100–7 Nu Draconis 86
O observation times for charts 19 occultations 119 October skies 92–9 Omega Centauri 39, 45, 53, 61, 63 Omega Nebula 79 Omicron-2 Eridani 103 Ophiuchus 54–5, 63, 68, 85 oppositions of planets 116–24 Orion 21–2, 37, 101, 103, 108–11 Orion Nebula 20–2, 102, 108–11 Orionid meteor shower 92 outer planets 18 see also Neptune; Uranus overview pages, using the sky guides 18
P partial eclipses 118, 124 see also eclipses Pegasus 84–5, 86–7, 92–3, 100 Perseid meteors 76 Perseus 92, 100, 109 see also Double Cluster Phoenix 93, 101 photography 15 Pisces Austrinus 77, 85, 93 planet locator charts, using planet locator charts 18 planets 18
January skies 21 February skies 29 March skies 36, 37 April skies 44–5 May skies 52–3 June skies 60–1 July skies 68–9 August skies 76–7 September skies 84–5 October skies 92–3 November skies 100–1 December skies 108–9 movements 13, 116–24 see also Earth Pleiades 37–8, 45, 94, 100–2, 108–11 Polaris (Pole Star) 11, 52, 60 poles, movement at poles 12 Pollux 28–9 Praesepe 28, 31, 36 Procyon 108 Puppis 29, 37
Q Quadrantid meteor shower 20
R RA (right ascension) 10–11 recording observations 15 red light flashlights 14 refractor telescopes 15 Regulus 44, 47 Rigel 21–2, 101, 108–9, 110 right ascension (RA) 10–11 Rigil Kentaurus 69, 77 Ring Nebula 68, 77–8 rings of Saturn 122 Rosette Nebula 28
S Sagittarius 61, 63, 69, 71, 77, 79, 85 satellites 124 see also Moon Saturn conjunctions 121 Moon passes 119 open rings 122 oppositions 116–24 “white spot” 124 Scorpius 52–3, 60–2, 69, 77, 85, 87 Scutum 76, 77, 85 September skies 84–91 Serpens 60, 68 Serpens Cauda 69, 71 Sickle of Leo 36, 44 sidereal days 12 Sirius 21, 29, 36, 101, 108 size measurements 11 sky guides see monthly sky guides Small Magellanic Cloud (SMC) January skies 21 August skies 77
September skies 85 October skies 93, 95 November skies 101, 103 December skies 109, 111 solar days 12 solar eclipses 13, 116–24 Solar System 8 Sombrero Galaxy 39 South Celestial Pole 29 Southern Cross see Crux southern latitudes January 21, 23, 26–7 February 29, 31, 34–5 March 37, 39, 42–3 April 45, 47, 50–1 May 55, 58–9 June 61, 63, 66–7 July 69, 71, 74–5 August 77, 79, 82–3 September 85, 87, 90–1 October 93, 95, 98–9 November 101, 103, 106–7 December 109, 111, 114–15 Southern Pleiades (IC2602) 31, 37, 45, 111 Spica 36, 37, 44–5, 52, 68 starhopping method 11 stars 10–11 January skies 20–7 February skies 28–35 March skies 36–43 April skies 44–51 May skies 52–9 June skies 60–7 July skies 68–75 August skies 76–83 September skies 84–91 October skies 92–9 November skies 100–7 December skies 108–15 magnitude 19 movement diagrams 19 see also galaxies; Sun stellar neighborhood 8 Summer Triangle asterism 68, 70, 84 Sun 8 see also solar superclusters 9 superior planets 13, 116–24 see also Jupiter; Mars; Neptune; Saturn; Uranus
T Tarantula Nebula 21, 101, 109 Taurid meteor shower 100 Taurus 100, 101, 108–9 Hyades cluster 23, 38, 102 Pleiades 37–8, 45, 94, 100–2, 108–11 “Teapot” asterism 69, 71 telescopes 15 Theta Carinae 37 Theta Eridani 103
total eclipses 122 see also eclipses Transit of Mercury 121, 124 of Venus 117 Triangulum Galaxy (M33) 93–5, 100–2 Trifid Nebula 69, 77, 79 Tucana 85, 87, 93, 95, 101, 103 see also Small Magellanic Cloud
U Universe, size of Universe 8 Uranus 18 January skies 21 February skies 29 March skies 37 April skies 44 May skies 52 June skies 60 July skies 68 August skies 76 September skies 84 October skies 93 November skies 101 December skies 109 conjunctions 116 Ursa Major 22, 30, 70 Big Dipper 36, 44, 52 M81 spiral galaxy 36, 44, 46 Ursa Minor 22, 60
V Vega 68, 70, 76, 92 Vela 23, 37, 109 Venus 13, 120 close approach 118 conjunctions 118, 122 elongations 116–24 Transit of 117 viewing locations 14 Virgo 36–7, 39, 44–5, 52, 68 Virgo Supercluster 9, 44, 46 Vulpecula 77–8
W XY Z Whirlpool Galaxy 52, 60 “white spot,” Saturn 124 whole-sky charts, using whole sky charts 19 Wild Duck Cluster 76 Winter Triangle 108 yearly movements 12 zeniths 19 zodiac 12
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A CK NOWLEDGMEN TS
ACKNOWLEDGMENTS Will Gater I’d like to thank my family for their continual support, especially Rose, as well as Martha and the team at DK Publishing for all their hard work.
Publisher’s acknowledgments DK Publishing would like to thank the following people for their help in the preparation of this book: Giles Sparrow for editorial and illustration guidance and Almanac text; Paul Drislane for initial design work; additional design help from Fiona McDonald. Indexing Specialists for preparing the index; Lizzie Munsey for proofreading. Additional production help from Sophie Argyris and Luca Frassinetti. DK images: Claire Bowers, Martin Copeland, and Lucy Claxton.
PICTURE CREDITS The publisher would like to thank the following for their kind permission to reproduce their photographs:
(Key: a-above; b-below/bottom; c-center; f-far; l-left; r-right; t-top) 2-3 Corbis: Gabe Palmer. 4 Corbis: Visuals Unlimited. 6-7 Corbis: Science Faction/Tony Hallas. 9 Corbis: Myron Jay Dorf
(b/Milky Way); NASA/JPL-Caltech (b/Quasar); Science Faction/ Tony Hallas (crb); Stocktrek Images (b/Andromeda Galaxy). European Southern Observatory (ESO): Digitized Sky Survey 2 (b/Virgo Cluster). 10 Corbis: Roger Ressmeyer (cra). 13 Corbis: EPA/Dean Lewins (tr). Will Gater: (bl). 14 Corbis: Gabe Palmer (cla). 15 Corbis: Frank Lukasseck (bc); Visuals Unlimited (cr). 16-17 Corbis: Frank Lukasseck. 21 Corbis: Roger Ressmeyer (cla). 22 Corbis: Visuals Unlimited (cl) (bl). 23 Robert Gendler: (br). Alson Wong: (cr). 28 NOAO / AURA / NSF: (cl). 29 Science Photo Library: Eckhard Slawik (ca). 30 Getty Images: Visuals Unlimited, Inc./Robert Gendler (bl). Walter MacDonald: (cl). 31 Corbis: Visuals Unlimited (cr). Science Photo Library: Celestial Image Co. (br). 36 Corbis: Roger Ressmeyer (cl). 37 Galaxy Picture Library: Gordon Garradd (cl). 38 Corbis: Roger Ressmeyer (bl); Stocktrek Images (cl). 39 European Southern Observatory (ESO): (br). NASA and The Hubble Heritage Team (AURA/STScl): (cr). 44 Getty Images: David McNew (cl). 45 Yuri Beletsky: (cl). 46 Corbis: Stocktrek Images (bl). NOAO / AURA / NSF: (cl). 47 NASA and The Hubble Heritage Team (AURA/ STScl): (br). Hunter Wilson: (cr). 52 Corbis: Roger Ressmeyer (c). 53 Yuri Beletsky: (cl). 54 NASA and The Hubble Heritage Team (AURA/STScl): (cl). NOAO / AURA / NSF: (bl). 55 NOAO / AURA / NSF: (cr). Télescopes à Action Rapide pour les Objets Transitoires: (br). 61 Corbis: Amanaimages/Katahira
Takashi (cl). 62 Will Gater: (cl). NOAO / AURA / NSF: (bl). 63 Getty Images: Image Bank/LWA (cr); Visuals Unlimited, Inc./ Robert Gendler (br). 68 Will Gater: (bl). 69 Corbis: Reuters/Ho (cl). 70 European Southern Observatory (ESO): Digitized Sky Survey 2 (cl). NASA: (bl). 71 Canada-France-Hawaii Telescope: Jean-Charles Cuillandre (br). Galaxy Picture Library: Jeremy Perez (cr). 76 Corbis: Reuters/Ali Jarekji (bl). 77 Corbis: Visuals Unlimited (cl). 78 Corbis: Scott Stulberg (cl). Getty Images: Stocktrek Images (bl). 79 Will Gater: (cr). NOAO / AURA / NSF: (br). 85 Corbis: Stocktrek Images (cl). 86 Frank Barrett: (bl). Galaxy Picture Library: Damian Peach (cl). 87 NASA: (cr). NOAO / AURA / NSF: (br). 93 Alamy Images: Galaxy Picture Library (cl). 94 Corbis: Roger Ressmeyer (bl). Galaxy Picture Library: Robin Scagell (cl). 95 Anthony Ayiomamitis/perseus.gr: (cr). Corbis: Dennis di Cicco (br). 101 Science Photo Library: John Chumack (cl). 102 2MASS: (cl). NOAO / AURA / NSF: (bl). 103 Corbis: Stocktrek Images (br). NOAO / AURA / NSF: (cr). 108 Getty Images: Barcroft Media/Wally Pacholka (cl). 109 Corbis: Roger Ressmeyer (cl). 110 Corbis: Roger Ressmeyer (bl). Galaxy Picture Library: Damian Peach (cl). 111 Getty Images: Stocktrek Images (br). NOAO / AURA / NSF: (cr). 117 Corbis: Richard Cummins (br); Reuters/Tim Wimborne (bc). 118 Corbis: Reuters/Bea Wiharta (tc). Pete Lawrence: (tr). 119 Alamy Images: Galaxy Picture Library (bc). Getty Images: SSPL/Jamie Cooper (br). 120 Corbis: Reuters/Doug Murray (tc). Jimmy Westlake: (tr). 121 Science Photo Library: John Sanford (bc). Mila Zinkova: (br). 122 Corbis: EPA/John Sun (tc); Roger Ressmeyer (tr). 123 Corbis: Gary Carter (bc); NASA/Bryan Allen (br). 124 Corbis: (tc). NASA: JPL-Caltech (tr).