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Simple Stargazing
Anton Vamplew
A first-time skywatcher’s guide from bright new talent, BBC Blue Peter astronomer, Anton VamplewMost books on stargazing claim to be for beginners, but by page 12 are talking about celestial equators and sidereal months. No wonder so many people have planispheres but no idea how to use them.Working at the planetarium in Greenwich, Anton has met hundreds of enthusiastic but utterly bemused beginners of all ages, and has made sense of the night sky for them. In this book he introduces the night sky just as if he were by your side, pointing everything out. And contrary to popular belief, you don't need any expensive equipment to start skygazing. Anton takes you through all the things you can discover with just the naked eye.The book is suitable for use in the northern and southern hemispheres – two sections give equal coverage to where to start and what you can see wherever you are in the world, whenever.
Contents
Cover (#u482212ec-ec41-5ae0-a904-9455fc77d3e7)
Title Page (#uab5dae45-de05-5c82-96a2-689a4abe0abc)
Dedication (#ubd2a4ae5-eb11-5e23-8409-6141f48e90d7)
Introduction (#u435ce41b-3da3-5d6c-b745-23b483dd51b5)
PART 1 (#u427618c6-38d8-5013-a005-a689d4966e36)GETTING STARTED (#u427618c6-38d8-5013-a005-a689d4966e36)
A Brief History (#ulink_25e6e215-33db-5e22-92c3-c05ae37a18e7)
Constellations (#ulink_0551d24f-c08f-56a2-954a-1ebd9687e1e3)
Adventures in Darkness (#ulink_35d059f2-e602-51dd-a18f-e996889efa2d)
Travels into the Darkness (#ulink_60a77276-487f-5ad8-a17c-169ec72c57e0)
How Big is the Darkness (#ulink_13a352bf-3910-5678-9872-befb32d548d1)
How to Use the Star Charts (#ulink_aed780f4-69dc-514e-b9dd-92849385e89b)
Bright or Dim? (#ulink_93980ded-d567-5ad5-ab63-1681f071a233)
Stars (#litres_trial_promo)
Starry Objects (#litres_trial_promo)
PART 2 (#litres_trial_promo)THE NORTHERN CHARTS (#litres_trial_promo)
January to March Skies (#litres_trial_promo)
April to June Skies (#litres_trial_promo)
July to September Skies (#litres_trial_promo)
October to December Skies (#litres_trial_promo)
PART 3 (#litres_trial_promo)THE SOUTHERN CHARTS (#litres_trial_promo)
January to March Skies (#litres_trial_promo)
April to June Skies (#litres_trial_promo)
July to September Skies (#litres_trial_promo)
October to December Skies (#litres_trial_promo)
PART 4 (#litres_trial_promo)SUN, MOON AND PLANETS (#litres_trial_promo)
The Moon (#litres_trial_promo)
Eclipses (#litres_trial_promo)
The Planets (#litres_trial_promo)
Planets and Days (#litres_trial_promo)
The Milky Way (#litres_trial_promo)
Watching Satellites and the ISS (#litres_trial_promo)
Comets (#litres_trial_promo)
Shooting Stars (#litres_trial_promo)
A Final View of Everything (#litres_trial_promo)
Astro Glossary (#litres_trial_promo)
Going Further (#litres_trial_promo)
Index (#litres_trial_promo)
Acknowledgements (#litres_trial_promo)
Copyright (#litres_trial_promo)
About the Publisher (#litres_trial_promo)
Dedication (#ulink_fbf99d6a-29b7-5998-9baa-36e0dd713129)
For Morten, Etienne and Dad
Introduction (#ulink_c4ba8962-1ae8-5b07-ab89-df2964a38d0c)
Prepare yourself for an adventure… that will take you deep into space and far back in time. This great journey begins the moment you cast your eyes up into the night sky. After a while you’ll be looking beyond the stars, wondering about distant life or maybe thinking just how fantastically big this whole Universe thing is.
I vividly remember when I was six, gazing out of my bedroom window with a desire to learn the names of the bright stars and the patterns I knew existed in the form of constellations. Little did I know what I had started – a lifelong trip which never ceases to amaze me. We are now in the age of Hubble, Cassini, Galileo, Hipparchos and Messenger (etc., etc.) – spacecraft that open up the vistas of the Universe to realms that excite while causing us to constantly rearrange our jigsaw of… well, everything. And this is not going to slow down. Look out for specially trained astronauts on the Moon and Mars, and ‘ordinary’ astronauts (that’s you and me) taking short trips into space.
Hopefully I can share some of my wonderment through these pages. None of this is rocket science (apart from the rocket science stuff). The name of the stargazing game is easy, short observing whenever you have a few spare moments while the stars are twinkling overhead.
‘Oh, but I can’t see the stars from where I live,’ is always a good one. Read carefully, as this will be written only once: living in a town, city or anywhere with light-polluted skies need not deter anyone from stargazing. Although the sky glow washes out the fainter stars, the major constellations will still be visible. So you won’t be hindered from learning the main star patterns. No excuse there, then!
Don’t underestimate the power of ‘doing’ something. Simply by taking a few minutes each day over the course of a year you’ll soon be amazing your friends as you point out Leo and say, ‘Of course, Regulus is a B7-type star about 85 light-years away.’ Or you might glance at the Square of Pegasus, remarking casually, ‘Messier 15 over there was discovered by the wonderful Italian, Maraldi.’ Or even dreamily waft your hand in the direction of Orion, and with a certain authority launch into, ‘The dimensions of M42 are 66 by 60 arc minutes.’ It won’t take long to learn the night sky, and I hope this book will inspire you to make a start.
The night sky is out there. As this old map shows, it’s all prepared and ready for you to explore.
Part 1 Getting Started (#ulink_cae2898c-0950-5dd8-8248-b3d983a75b9a)
A fine sunset is worth a picture itself as well as the hint that it’s going to be a fine, clear, starry-skied evening. Just the prompt you need to get you into the stargazing frame of mind.
A Brief History (#ulink_5ee85514-7a20-5924-8900-008e1fcc9f72)
In the distant past, astronomy and astrology were as one. Ancient rulers needed to know their fortune and, as the sky was where their gods lived, it was also where their destiny lay. Along with all the ‘fixed’ stars of the constellations were seven things that moved: the Sun, Moon and five planets – Mercury, Venus, Mars, Jupiter and Saturn (this was, of course, in the days when everyone believed that the Earth was the centre of the Universe and other sky objects moved round it).
It was an absolute belief that leaders who could understand how these objects moved could stay in control and defeat their enemies. One thing was clear: to these ancient watchers of the skies these seven objects followed a ‘path’ around the heavens – just like a car on a race track that takes the same route round again and again. It was the constellations situated along this ‘path’ that became our 12 famous signs of the zodiac.
Of course, in order to know where any object would be in the zodiac at any given time, a certain amount of calculation was required. This is when the science of astronomy was born. So, strangely, the necessity for fortune-telling encouraged the formation of science. By the way, zodiac means ‘line of animals’ (11 of the original 12 constellations are still animals) and is also linked to the word zoo.
So, why do the planets, Sun and Moon appear to move through the skies? Well, they each appear to move for different reasons. Of course the main movement you see is due to the Earth spinning – this gives us things like sunset, the Full Moon rising over frosty trees, time for your cornflakes for breakfast as the Sun rises, etc. The Moon, if it is up, additionally appears to move extremely slowly hour by hour in front of the stars because it is orbiting the Earth. The Sun changes its position against the stars day by day due to the fact that we are orbiting it. The planets move because they too are orbiting the Sun – plus each planet is moving at a different speed. No wonder it was all difficult to calculate, and indeed it’s hardly surprising that some early astronomers ended up having their heads chopped off, when their erroneous adding up was followed by a total overreaction from their bad-tempered rulers.
Constellations (#ulink_2a882bd8-6e65-53e9-8b2b-8cc4822cdb25)
A word worth defining before we launch ourselves into space is constellation. It’s based on a word from Latin meaning ‘group of stars’. In total you’ll find 88 of them filling the entire sky, but thankfully you don’t need to know them all to enjoy the hours of darkness. Other starry terms that crop up throughout the book are written in bold and explained in the AstroGlossary in here (#litres_trial_promo).
The story of organising things up there in the darkness of the night began thousands of years ago with civilisations such as the Sumerians, Babylonians, Egyptians, Greeks and Romans (as well as many other cultures from around the world). They decided the starry skies could do with a bit of order and a tidy up. So they joined up many of the stars, just like a dot-to-dot picture, putting their myths and legends into the sky as they did so.
Don’t think that there was any rhyme or reason for making a particular pattern. For example, Cepheus, King of Ethiopia, and his wife, Queen Cassiopeia, both have constellations named after them, and yet these look like a house and a set of stairs respectively. Imagination is the key here, I feel. As far as these early civilisations were concerned, the gods and goddesses needed a place to reside in the starry vault, so it was probably a case of first come, first served, and pot luck as to which stars were assigned to which group.
We get our earliest knowledge of the constellations from Aratos, the first Greek astronomical poet, in his work Phaenomena (which was probably based on an earlier ‘lost’ work by another Greek, Eudoxus). Then in AD 150 Ptolemy, a Greek working at the great library of Alexandria in Egypt, recorded them in a book known by its Arabic name, Almagest, which means ‘the greatest’. Hundreds of years ago, other astronomers who wanted to be famous added extra groups (some more successfully than others) to give us our present fixed total of 88 constellations.
Constellation names are traditionally written in Latin. This is because Ptolemy’s book was brought from the Middle East to Italy, where it was translated – and Latin, for centuries, was the language of scholars. So, for example, we know the Great Bear as Ursa Major.
Here are all the 88 constellations of the starry skies. Details of those with interesting things to see are given in Parts 2 and 3.
Adventures in Darkness (#ulink_10a1ed62-fe45-5c37-8cc8-96a20e51f7df)
Right, you’ve opened the door and are standing in the garden/yard/field/outback/ savanna/rocky landscape/swamp, etc. gazing up at the night sky searching for something wonderful to appear. How many stars can you see on a clear night? Millions? Squillions? Zillions? In fact, away from light pollution, with a good low horizon, the maximum number of stars you can see at any one time is 4,500(ish). Count them if you don’t believe me. Of course, if you live in a major city, then bright orange skies can easily reduce this number to less than 200, so the darker your location the better.
A few things to start with…
Step-by-step guide to stargazing
1
Before you go out, check where the Sun rises and sets from where you live. This will give you some idea of where to look when trying to find something in the night sky. Usefully, around 21 March and 23 September, the Sun rises exactly east and sets exactly west. However, in the northern hemisphere during the summer months the Sun appears (roughly and depending on the precise date) somewhere from the northeast and sets somewhere northwest, while in the winter it’s a southeast rise and a sort-of southwest set. In the southern hemisphere, the summer Sun rises somewhere in the southeast and sets somewhere southwest, while winter sees a northeast rise and a northwest set.
2
In order to see the most stars you need to let your eyes become accustomed to the dark. This is called dark adaptation. Ten minutes is a good time to sit in the dark without the lights on. Ponder, cogitate and muse over the wondrous spectacle that you are about to marvel at. How many constellations will you find? This process of dark adaptation not only widens your pupils to let in more light, but also allows various chemical reactions to take place in your eyes and activate your light-recepting rod cells. Now you will be able to see all those faint stars.
Help your dark-adapted eyes by making sure any torch is covered in red plastic.
3
Whilst outside in the dark the only way to see where you’re going, or to look at the great star charts in this book, is with a torch. However many you decide you need, each should be covered in red plastic or something similar. The resulting red light, you see, hardly affects your now dark-adapted eyes.
4
Grasp this book firmly and, if you are not one yourself, find a responsible adult and venture outside. Adults are very useful indeed for chatting to and for having someone who will marvel at your initial determination.
Where exactly to begin up there depends on where you live down here. For those in northerly climes, you need to go here (Northerly humans start here (#u29e4b815-b4cb-4f5f-9cbc-e34285901d93)) … while southerly humans go here (Southerly humans read this (#ud0565a60-25cc-4f24-9ad3-c023dce2ca46))…
Empty space – or is it?
Northerly humans start here
Just look at the page opposite: it’s covered in what looks like a chaotic pattern of differently sized dots. Nothing could be further from the truth. Each dot is actually a star we can see in the night sky and, just like many things that look like chaos to start with, there’s order within this mess.
Lurking within these dots you will find a very useful pattern that is probably the best place to start your stargazing quest in the northern hemisphere. This group is known affectionately as the Plough – well, it is in Britain. Moving around our planet, we find that the Plough is called Karlsvogna (Carl’s Wagon) in Norway, the Big Dipper in the USA and the Saucepan in parts of France. This is definitely a good name for the shape, as you can see – a pan with a handle stretching out to the left. Anyone for space beans?
Now, the Plough is not actually a constellation itself, but part of a much larger group called Ursa Major, the Great Bear – we shall meet it very shortly.
The Plough is always visible from mid-northern latitudes if the skies are dark and the weather crisp and even. Also, all of its seven stars are quite bright, making it an easy group to find. In order to know which direction to look to find The Plough, you need to have some idea of north, south, east and west. As I said a moment ago, the Sun sets in the west(ish), so look to the right of that and up a bit (that’s a technical term) and there’s the Plough in the north(ish). Easy.
It’s not long before patterns begin to emerge from the ether. Ether is an old term for the stuff that scientists used to believe filled space – it doesn’t exist, but the idea’s nice.
Round and round the Plough goes. If you are far enough into the northern hemisphere, this is where you’ll find it at 8 p.m.(ish) at certain times through the year. The left of the diagram is the direction of northwest, whilst the right is northeast.
Because the Earth is constantly turning, don’t expect the Plough to stay in the same place for long. There’s also our movement around the Sun to consider, which means that each night at the same time the Plough will be in a slightly different position. How exciting is that!? Generally you’ll find the Plough higher in the sky during spring and summer evenings, and nearer the horizon in autumn and winter evenings.
As you may have noticed, there is a well-known star ‘locked’ in the centre of the image that the Plough rotates around. This is Polaris, also known as the North Star, or indeed the Pole Star. This last name means that it is the closest star to the North (Celestial) Pole, but because of the way the Earth spins on its axis, this is a temporary title and has been held over millennia by a number of the stars featured in this book.
You can always find Polaris by using the two right-hand stars of the Plough, which are called the Pointers. No need for Sherlock Holmes here – these two stars, Dubhe and Merak, simply ‘point’ up out of the ‘saucepan’ to Polaris. Elementary. And this is just one reason why the Plough is so useful. Through this book you’ll find plenty of ways that it can be used as a ‘signpost’ to many other stars and constellations.
The Pointers of The Plough doing their ‘pointing’ thing.
Polaris is the leading (main) star of Ursa Minor, the Little Bear.
Now, to break a myth: the North Star is not the brightest star in the night sky. It seems that for some unknown reason someone, somewhere, sometime told us that not only was it the brightest but it was also the first star you could see when it got dark. This is not true: Polaris happens to be only the 50th brightest star in our skies. Its fame is due to its position: almost directly above the North Pole. As the Earth spins we see the effect as the sky spinning, and in the northern hemisphere it’s Polaris that everything goes around. Being almost stationary in the sky means that if you’re looking at it you are looking north. And if you know where north is, you also know where east, south and west are. This is why Polaris was great in the olden days when mariners would ‘sail by the stars’.
There’s another group that can be found with supernoval ease by carrying on the line from the Pointers through Polaris to a ‘W’ shape that is Cassiopeia, the Queen. If your house/flat/hut/cave/tent/treehouse, etc. is in a position where the Plough never sets, then neither does Cassiopeia – they’ll both be up, somewhere. Because they are on opposite sides of Polaris, when the Plough is high, Cassiopeia is low and vice versa.
Following imaginary lines made by stars can lead you anywhere in the Universe.
Cassiopeia, the Queen, sits and ponders: ‘Hmmm, I know I’ve forgotten something?’
Southerly humans read this
Travelling to the southern part of the world, where the Plough may only be visible for half an hour in mid-April, or indeed may have totally vanished below the horizon, we need something else that can help us on our stargazing travels. Indeed, as for seeing the Plough (even for the briefest of periods), places near 23°S, like Alice Springs, Australia, São Paolo, Brazil, or Gaborone, Botswana, are really your most southerly locations.
A comparison in size between the Plough, a part of Ursa Major, and Crux, the Southern Cross.
