Andrew Newsam - Everything You Ever Wanted to Know About the Universe: And Our Place Within It

Everything
You Ever
Wanted
to Know
About the
Universe

Everything
You Ever
Wanted
to Know
About the
Universe

And our place within it

ANDREW NEWSAM

How does that work? It is a question we have all asked ourselves many times, and that curiosity which goes beyond the necessities of life, and picks and niggles at everything around us is arguably the spark that gives humanity its special place in the animal kingdom. Out of curiosity has grown science a powerful set of techniques for answering questions and sharing what we learn. Much of what we have discovered has been practical and aimed at day-to-day problems and challenges. Whether it is biology giving us the knowledge of life that drives medical advances, the insight from chemistry that allows us to create better, more versatile materials, or physicists discovery of the electricity that powers our modern world, science can claim many advances that have benefited everyone (as well, of course, as a few more worrying improvements). But some areas of science have less obvious practicality, of which astronomy is the most obvious example.

So, what is the point? Why do we spend so much time and effort studying things far beyond the Earth some so far away that by the time we see them, they probably do not even exist anymore? It is tempting to highlight the unexpected practical benefits, of which there are many. Helium was first discovered by studying the Sun, and it now plays a vital role in many fields as a refrigerant (not just for party balloons and silly voices!); digital cameras and the advances in computing that have revolutionised many of our lives were driven in part by the needs of astronomers; and even esoteric, theoretical physics such as Einsteins General Theory of Relativity is now vital to GPS and SatNav systems, over a hundred years after it was formulated.

But to me, these examples miss the point. Yes, it is always good to find new and valuable ways to use knowledge and discoveries, but the driver is, and must be, pure curiosity the need to know. The fact that you have picked up this book is a sign that you are also curious and have that desire for discovery, and what better to be curious about than the whole of existence and our place in it? Welcome to astronomy.

Taking an interest in astronomy can be as simple as looking up. The night sky is open to anyone. With the increase in street lighting and pollution it is getting harder and harder for us to see but, nevertheless, on any clear night there is always something to look at, even in the middle of the largest, most over-crowded city.

The first and most obvious thing to look for is the Moon. It is a common sight, but surprisingly few people take the time to really look at it. One of the most wonderful things about the Moon is how much it changes when viewed through even the smallest telescope or binoculars. I carry a tiny telescope (about the length of my little finger) with me all the time, and when I spot the Moon, I usually take a moment to look at it in close-up. This is particularly special when the Moon isnt full and the terminator (the dividing line between dark and light) is clear, showing the jagged line of mountains and their shadows. If you are lucky you can even catch tiny bright spots just into the dark side of the Moon where the rays of the Sun catch the tops of mountains.

Also visible even in light-polluted skies are the brighter planets: Mercury, Venus, Mars, Jupiter and Saturn. You have probably seen them many times without realising. Unfortunately, they move around from night to night and month to month, and are often not in the night sky at all, so knowing where to look is not always straightforward.

Venus is usually easy to spot when it is up, though, as it is one of the brightest things in the night sky (second only to the Moon) and is visible either in the west just after sunset, or the east just before sunrise. If you see a very bright star-like object in the fading glow of sunset, and it doesnt move or blink, it is probably Venus (if it moves or blinks, it is probably a plane). You may also notice that it will twinkle rather less than any stars visible at the same time. This is characteristic of the planets, so can be a good way to spot them a star that does not twinkle is probably not a star.

Once you have found a planet, working out which one it is can be tricky. Mars has a distinctive reddish tint, but Saturn and Jupiter both look quite similar (Jupiter is somewhat brighter, but that is only obvious if they are both visible at the same time). To know for certain, you will probably need to use a star map for the right night. Many newspapers publish such things every day, and lots of websites also have them, but they are increasingly being replaced by smartphone sky apps.

These apps are a huge boon to any stargazer. Rather than having to remember constellations, star names, and the slow dance of the planets, they use the location technology within your phone to show you exactly what you are looking at, often overlaying the names and constellation patterns onto the view through the phone camera. With even the simplest, free apps, anyone can become an expert in the night sky in minutes.

Of course, while more can be seen in a bright city than you might expect, the darker the skies are, the more there is to spot. However, you do not always have to go to the middle of nowhere to see interesting things. Even a relatively dark place in a city or town can make a big difference. In such places parks, back gardens, unlit streets as your eyes adjust to the dark, you will begin to see more stars and perhaps the patterns of some recognisable constellations and nebulae: Ursa Major, sometimes called the Plough or the Big Dipper; Polaris, the North Star always due north; the distinctive W shape of the constellation Cassiopeia; Orion, shaped like a man with broad shoulders; the Pleiades, or Seven Sisters; and in the Southern Hemisphere, the Southern Cross and Centaurus.

But to see the sky in its full glory, with its numerous nebulae, countless stars and the glowing band of the Milky Way, you need a bit more than a dark-adapted eye. You have to find somewhere truly dark and clear. Fortunately, there is an international effort to find and conserve the best dark skies the International Dark-Sky Association or IDA. Still growing, the IDA has an ambitious aim to create a complete map of the best places to observe the sky, so wherever you are you can find somewhere reasonably nearby with suitable dark skies (although good weather may be more of a challenge). You will be amazed at the variety and beauty of the heavens.

Of course looking is only a small part of astronomy. The other part the part that most excites me is trying to understand what it is youre seeing and make sense of it all. Sometimes this can seem complex or even overwhelming, but dont be put off.

One of the things people struggle with is the vast scale of the universe. Even in our own solar system, the Moon might seem far away but the Sun is more than 400 times further away, and Neptune tens of times further away still. Once we leave the Solar System, the next things we find are the nearest stars not just a few tens or even hundreds of times further away than Neptune, but around 10,000 times the distance. It can be very hard to get your head around such huge numbers.