BBC Stargazing LIVE Part 1: Introduction and how to choose a telescope

To celebrate BBC Stargazing LIVE, we’ll be posting a number of astronomy-themed articles and competitions this week, beginning with a guide to understanding telescopes.

comments

Tomorrow at 8pm the latest series of BBC Stargazing LIVE begins on BBC Two, culminating this Thursday. It’s a great way for amateur astronomers to get started in the field, and to compliment the BBC’s show we’ll be giving you tips and tricks throughout this week to help you become a well-rounded amateur astronomer. Whether you’ve just received a shiny new telescope for Christmas, or you’re perfecting an existing hobby, we’ll have some great advice to help you make the most of your time observing the night sky. Our first article below takes a look at the different types of telescope.

Understanding telescopes


Mouse over the icons to get to grips with the different parts of a telescope

Telescopes come in two basic types; reflectors and refractors. Reflectors, as the name suggests, use mirrors to gather and focus the light from the stars, whereas refractors use lenses and are what most people consider to be a ‘telescope’. The old naval ‘spyglass’ is a refractor. There are other types, but they are really just variations of these main two.

Refractors are often a good telescope type for beginners to get started with as they are easy to use and maintain. They tend to be smaller than reflector telescopes and so can be easier to handle and store and are good for viewing the Moon and planets. Reflectors, on the other hand, are great telescopes for seeing what are known as ‘deep sky’ objects; these include star clusters, nebulae (clouds of gas) and distant galaxies. There is a lot of crossover though and both types of telescope should show you most things quite well.

When buying your first telescope there are a few things you should consider. Not least its size and weight; a smaller telescope might not show you as much, but if you use it more often it will be worth more to you. Also think about how the telescope is mounted. The simplest type of mount, known as an ‘altazimuth’, is probably adequate for most viewing purposes. If you plan to start doing some astrophotography, however, you will almost certainly need an equatorial mount which takes a lot more setting up and understanding.

There are some telescopes now that have computerised mounts which will, once set up, slew the telescope to hundreds or thousands of different objects in the night sky and track them for you. This might sound attractive, but remember that a sizeable proportion of the price has gone on the technology and so you will get a smaller aperture telescope for your budget. If you’re still unsure seek advice before you buy.

Tags: , , , , , , , , , , , , , , , ,