Astronomy telescopes vary by type, aperture size and features, but what they all have in common is that they use lenses or mirrors to collect light and create an image of the celestial object you’re observing. Some use only one lens, like a pair of simple magnifying glasses, while others have multiple lenses to create a wide field of view, and some use a combination of both refraction and reflection (catadioptric) design to offer a wider range of optical features.
There are also various ways that a telescope can be mounted on a tripod, which can affect how well it tracks objects as they move across the sky. In general, a telescope with a longer focal length will be better for viewing objects that take up larger sections of the sky such as galaxies and nebulae, while a telescope with a shorter focal length is better suited to planets and moon viewing as they can achieve higher magnifications with their smaller aperture sizes.
In addition to the aforementioned lenses and mirrors, astronomy telescopes also incorporate eyepieces, which are the magnifying lenses that attach to the end of the telescope tube and give you a view of the object you’re looking at. These come in a variety of designs, from basic Orthoscopic models that are a bit like looking through a soda straw, to exotic wide-field options that are more like sticking your head into the bubble-shaped observing port on the International Space Station.
Most telescopes are affixed to a mount that can track objects as they move across the sky, called an equatorial mounting. If you’re just getting started, you can get away with a simpler mount that slews the telescope from side to side and up and down, called an altazimuth mount. The Celestron Astro Fi 102 is an excellent example of a beginner-friendly altazimuth telescope.
This is a Maksutov-Cassegrain telescope with a f/4.5 focal ratio, which means it can see more detail in a smaller aperture than other scopes with a similar or even larger aperture. It’s a good choice for beginners as it’s relatively easy to set up, has motorized tracking so you don’t have to manually slew the telescope to your chosen target and is in a very affordable price bracket for a Maksutov-Cassegrain scope. However, it doesn’t have GoTo technology, so you’ll need to be confident enough locating objects yourself or with the help of a stargazing app to make the most of it. Its compact size and lightweight mount also make it a great option for travelling to dark-sky locations. The lens cap also doubles as a smartphone holder, which is a neat trick that makes this an ideal telescope for astrophotography. As an added bonus, it’s designed to reduce the effects of light pollution and can be used in urban areas without sacrificing performance. Click for the full review.