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Observing with a small telescope

by Alistair Thomson

At this point I decided it was time to invest in a telescope. This was much harder than I first expected. I gathered as much information as I could on the various types of telescopes. The one piece of information I was missing was the answer to the question “ What can you see through a small telescope?”. The answers I received were vague at best. In the end I decided to invest in an Orion Europa 6” Reflector on an equatorial mount (This is Orion in the UK).

At first I was quite surprised at how difficult it is to locate objects in the sky with the viewfinder. This was mainly due to the level of light pollution I suffer from in my back yard – I’m the unhappy ‘owner’ of two sodium street lights. The only way I got past this hurdle was to use the technique of star hopping to find the object I was interested in. This was a little more difficult than I first thought. I ended up looking for objects that were close to easily identifiable stars. This brought quite a bit of success and I managed to track down the open clusters in Auriga. They were a remarkable sight in the telescope showing many stars instead of the grey cloudy patches I had become used to seeing. Most of the observing I did in the first year was of open clusters and a few globular clusters. I wasn’t having much luck with globulars as I could never resolve any stars in them.

I now turned my attention to the planets, I had Saturn, Jupiter and Mars high in the sky. Mars was a little disappointing but Saturn and Jupiter – WOW. These were fantastic. Saturn has to be one of the most fantastic sights in the night sky. The planet is a orangey yellow colour and the rings showed up well casting a shadow on the planet that is clearly seen. Jupiter was just as magnificient. I could quite easily make out three major cloud bands running around the planet, by using the 25mm Kelner I could also keep track of Jupiters four main moons. All this from a light polluted back yard!

After the planets went by I started back on the Messier objects. I was keen to find my first galaxy. After many attempts over the winter I gave up, I just couldn’t see them and I was sure I was looking in the right place. This also went for planetary nebulae. The globular clusters I found were all just round grey blobs, some were a little brighter than others. Even M13 in Hercules didn’t show any stars and this is supposed to be the best example of a globular. I was starting to get a bit disillusioned.

Anyway, I live in the UK and we don’t get very many clear nights, when we do it always seems to coincide with a full moon! When this was the case I started to put a web site together just to keep my interest in astronomy going. One of the pages I added was going to show reports of my observing sessions. To date I had never kept a report of what I’d seen. I now regret this.

This Spring I decided I would once again try for a galaxy. I prepared the star charts I would use to locate the target. I was going for M65 and M66 in the constellation of Leo. To my delight I found them! Here’s an extract from my web page on how I found them:

“Hopped from J to 73 (by moving south halfway between J and i ) and centred on a small star to the east of 73 (they're in the same field of view with a 25mm eyepiece). Both galaxies are very faint and would be easily overlooked if you didn't know they were there! They're slightly above the small star centered in the eyepiece. M65 was elongated in shape and quite thin. M66 was larger in size and not quite as elongated as M65. There appeared to be a band diagonally through the galaxy that wasn't visible giving the impression that the galaxy was split in two. There were also two small stars in the same line of sight that appeared to be sitting on top of the galaxy.”

I then read about the double star Mizar and Alcor in Ursa Major, I had viewed this pair quite a few times before but had totally missed the fact that Mizar itself also had a companion star. The next clear night I checked it out, sure enough there was the companion star. I had missed it every other time I had looked at the pair!

I realised that I hadn’t really been looking hard enough at the objects I was viewing or really appreciated just how faint or small some of these objects can be. I now feel much more motivated to finding these elusive objects in the sky.

My next targets are going to be planetary nebulae, starting with M57. Many observers have published reports on my website saying how good M57 looks and they’re using telescopes smaller than mine! Now I understand better what I’m looking for I’m sure I’ll find these objects. I’ve also realised just how important a dark sky is and I shall be visiting my local rugby club this coming winter, they have a lovely dark site in the middle of nowhere….. Roll on winter and I bet I’ll resolve some stars in M13 this time.

This article was written by Alistair Thomson.

Alistair has been an amateur astronomer for 3 years. If you would like to learn more about observing with small telescopes, please visit his web site at (http://www.geocities.com/the_150mm_reflector), a site dedicated to helping those with telescopes of 6” or less.






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