Question: How do telescopes work?

James Gilbert answered on 17 Jun 2015:

Well there are two main types of telescopeS

Optical telescopes use mirrors and lenses to focus light from the sky – just like a camera. These are the telescopes I work on. The bigger the telescope, the more light it can collect and so the more faint objects (further away) it can see. We’re discovering more and more stuff all the time.

The other type of telescope is a radio telescope, and these look like huge satellite dishes. They detect a different part of the electromagnetic spectrum (radio rather than visible light) which means they sense different things happening in the sky. Radio telescopes can see certain types of highly energetic explosions and certain types of black hole that optical telescopes can’t.

Hope that answers your question!