telescope

CE5

Mirror arrangements for a reflecting telescope

telescope, traditionally, a system of lenses, mirrors, or both, used to gather light from a distant object and form an image of it. Traditional optical telescopes, which are the subject of this article, also are used to magnify objects on earth and in astronomy; other types of astronomical telescopes gather radio waves (see radio astronomy), X rays (see X-ray astronomy), or infrared or ultraviolet radiation.

Sections in this article:

• Introduction
• Reflecting Telescopes
• Refracting Telescopes
• Mounting the Telescope
• The Schmidt Telescope and Other Innovations
• Arrangement of Mirrors in a Reflector
• Resolving and Magnifying Power
• Images Produced by Optical Telescopes
• Types of Optical Telescopes
• Bibliography

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