A telescope is a device used to form images of distant objects. There are two kinds: an optical telescope uses lenses and is known as a refracting telescope or a refractor, and a reflecting telescope, which uses a mirror and is known as a reflecting telescope or a reflector. The earliest telescope was a refractor built by the Dutch eyeglass maker Hans Lippershey. This category is for questions related to telescopes, including using them to view distant planets and objects in space.

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