Astronomy for Beginners

14 Aug 2014

I often get asked at my telescope viewing shows what is a good entry level telescope. A good way to start your astronomy hobby is with a pair of binoculars.

That's how I started as a kid. In fact I use this as part of my Astroexclusive sessions at Dubbo Observatory so guests can explore the skies as well as looking through the telescopes. You will be amazed at what you can see with binoculars and an excellent way of learning and navigating the night sky.

The other good thing is that if its just a fleeting interest you can always use binoculars for other interests like watching sports, use on holidays, birdwatching or other hobbies. It wont sit at the back of the shed gathering dust. Its also very portable and does not take up too much space. If you then get into it more as a hobby you can then go out and purchase your first telescope.

You want a pair that is light weight so it is easier to hold them steady for a period of time. To view objects properly you do need to keep them steady. You can improvise using the roof of your car, a step on a ladder. the fence or whatever. Lay back on a deckchair or trampoline and rest your elbows on your chest always works as well. Or better yet, purchase a stand or tripod.

Purchase them from a reputable telescope shop. They should be better quality. You want them to last many years. Cheap ones may not last long. They inevitably become bumped and so you want binoculars that loose their collimation easily and you see double images. Make sure they have a warranty and ask the shop owner what it covers and does not cover. They are expensive to repair. You pay for what you get. I still have my Dads binoculars, and they are still great at 50 years old.

Ideally its best to go into a store and try them out so you can get a good feel for them and see what suits you best while being able to get advice from a professional. Alternatively if you have access to a friends or go to a local astronomy club viewing night.

There are different strengths. They are often labelled a number x number. e.g. 8 x 40. This means 8 times magnification and an aperture of 40mm. The aperture is how wide the lens is. The wider the lens is, the more light that enters the binoculars and the brighter objects appear. Also the larger the aperture, the heavier the binoculars maybe as well. Ensure that you can adjust the ocular in the binoculars. If you cant it means you may not achieve perfect focus unless you have 20 20 vision. Usually we have one eye stronger than the other. To adjust this look at something easy like the Moon. Close one eye (the one that has the ocular adjustment) and focus the binoculars on the Moon. Swap eyes now. If its a bit blurry, adjust the ocular setting so it is in focus for that eye. Using both eyes now, view the Moon and refocus if necessary. It should now be quite clear.

Ensure the binoculars you purchase can have the distance between each side be adjusted so it fits you comfortably.

What are good things to look at?

The obvious thing is The Moon, and it is different each night as the phase changes allowing you to see different features. You will notice the "seas" craters, and these weird craters with radial lines coming out from them. These are relatively new craters.

The planet Jupiter is great in that you can see the moons. Watch them night to night and you will see them changing position as they orbit the planet just like Galileo observed for the first time back in 1609, hence they are called the Galilean Moons.

I used to map them night to night as a kid which really got me interested.

The next thing are star clusters. If you don't have a star map, just follow the milky way across the sky. The southern hemisphere winter and early spring is the best time. You will find heaps of hidden gems there.