Telescopes as a hobby is quite rewarding and they go of course hand in hand with the study and pursuit of astronomy. This is a guide to help you understand what telescopes are all about. There are many astronomers and amateur astronomers that are very passionate about telescopes - and for good reason. The scope is the thing that makes astronomy spectacular.
How a telescope works- A telescope bends light, pretty much as simple as that. And you probably already know this but you might not know that there are a couple of different ways that telescopes can bend light. The first and most common way is through a lens. The second way is by bouncing the light off a mirror with a curved surface. This gives us the two major types of telescopes: Refractors and Reflectors. And in the pursuit of telescopes as a hobby these two types are very different in performance and in price.
The Refractor Telescope This is an image of a refractor telescope and it is what we usually think of when we think telescope. There is a big lens on one end and a small lens or eyepiece on the other end. The light comes in through the big lens and travels the length of the tube down to the little lens where you look in.
The Reflector Telescope
The reflector telescope gets its name because it uses a mirror to reflect light back up the tube and this mirror is parabolic shaped (depressed in the middle like a saucer or bowl) so it bends the light as it is reflected. The light is bounced back up to the tube to a secondary mirror that bounces it out of the tube to the eyepiece where you look.
Bigger and Better Telescopes are Important
The following pictures give you a little bit of an idea when it comes to using a telescope. The first picture of the moon is what you might expect with a small telescope. The second picture would be something you could see with a larger and more expensive telescope. The important thing to note is that the larger and better the telescope the closer in you can zoom to things and still see them clearly. This is important. With a small telescope you could zoom into a crater but the picture would be very faint and very fuzzy. So, bigger telescopes and better built telescopes are what astronomers are always looking for.
Picture by Luc Viatour
Picture by NASA
There are lots of other objects in the night sky that you can see with a telescope. A good example of this is the Orion Nebula which is a gaseous formation in the constellation of Orion. If you were to look at it with a six inch telescope on a good night it might look similar to the picture on the left.
And this picture gives you an idea of how things change when you use a bigger and beter telescopes. Aside from the bigger image you see better definition and even some color.
Reflector telescopes are often the choice for astronomers
I told you a little bit about how the larger the telescope the better it is and it is for this reason that the reflector telescope is more frequently used by astronomers. It is much less expensive to make! You can get a much larger telescope for the same price. So, if you want maximum viewing you should consider the reflector - it is cost effective.
Using the Telescope
There are thousands of objects in the night sky like planets, comets, asteroids, nebulae, galaxies and more that can't be seen by the naked eye or just appear to be a faint star. But with a telescope these things come to life. With a telescope you can find these things in one of two ways.
The old fashioned method: If you have a beginners telescope or a simpler telescope you would use a star chart to find these various objects. You do this by recognizing the constellations and stars that are bright then moving the scope from one of these objects over to where the desired object is. This is the old way of doing it and it is quite adequate, even a bit fun. Kind of like a hunt!
The new method: Many of todays telescopes come with a GPS system that will automatically find these objects for you. You simply type in a reference number and the scope will move to the right location! Wow, things have come a long way. But, you of course have to pay for this kind of performance and expect to pay extra for this ability.
Some additional thoughts on you using a telescope
The darkness of the sky is very important when it comes to how well a telescope performs and how much you will see with it. So, if you live in a city you might want to consider the fact that to get really good viewing you may need to pack the scope into the car and take it away from the city lights. But, it is well worth the trip. You will be stunned by the difference.
The Expense to get started
There is the initial cost of buying a telescope and this can vary greatly but if you are on a tight budget you can get something for between $50 and $150. After that you might need a book or start chart. Then the continuing costs are almost non existent unless you want to upgrade to a bigger and better telescope.
Books and Star Maps
Quality Telescopes for Beginners
Here are a couple of recommendations from me on what telescope to get if you are a beginner, want to dabble in astronomy and want to get a decent telescope without much of a financial investment.
An amazing little telescope with computer controlled goto which will automatically point the telescope at 4,000 different night sky objects. The price is remarkable and the company is a leader in the industry.
This is a good example of how reflector telescopes can have bigger apertures yet be less expensive. Nice little scope at a very reasonable price and made by a great company.
Resources and more
- The Telescope Nerd Website - all kinds of interesting information about telescopes, how to use them and how to make them.
- Amazon.com Telescope Buying Guide - This is nice guide right on the amazon.com website that will help you decide on what type of telescpe is right for you.