Telescope - Related lists

A telescope (from the Greek tele = 'far' and skopein = 'to look or see'; teleskopos = 'far-seeing') is an optical tool which gathers and focuses electromagnetic radiation. Telescopes increase the apparent angular size of distant objects, as well as their apparent brightness. Telescopes are used for astronomy and in many non-astronomical instruments including theodolites, transits, spotting scopes, monoculars, binoculars, camera lenses and spyglasses. The word "telescope" usually refers to optical telescopes, but there are telescopes for mo ...

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• Telescope - History
• Telescope - Types
• Telescope - Telescope mountings
• Telescope - Research telescopes
• Telescope - Imperfect images
• Telescope - The five Seidel aberrations
• Telescope - The chromatic aberrations
• Telescope - Famous optical telescopes
• Telescope - Related lists

Read more here: » Telescope: Encyclopedia - Telescope

The first telescopes may have been Assyrian crystal lenses. Article The Visby lenses tentatively suggest that the technology was known to the Arabs and Persians then to the Vikings in the 10th century. Leonard Digges is sometimes credited with the invention in England in the 1570s, but usually credit for assembling the first telescope is usually given to an unknown Dutch spectacle maker in about 1608. Some name that person as Hans Lippershey (c1570-c1619), but Jacob Metius and Zacharias Jansen also claimed to have invented a telescope ...

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Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - History

The first telescopes may have been Assyrian crystal lenses. Article Though the Visby lenses tentatively suggest that the technology was known to the Arabs and then to the Vikings in the 10th century, credit for assembling the first telescope is usually given to an unknown Dutch spectacle maker in about 1608. Some name that person as Hans Lippershey (c1570-c1619). Even if Lippershey did not make the first one, he publicized it. Galileo Galilei made his own telescope in 1609, calling it at first a perspicillum, and then using the ...

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Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - History

A simple telescope mount is an altitude-azimuth or altazimuth mount. It is similar to that of a surveying transit. A fork rotates in azimuth (in the horizontal plane), and bearings on the tips of the fork allow the telescope to vary in altitude (in a vertical plane). A Dobsonian mount is a type of altazimuth mount which has proven to be very popular as it is simple and inexpensive. When using an altazimuth for astronomy, both axes must be continuously adjusted to compensate for the Earth's rotation. Even if this i ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Telescope mountings

Most large research telescopes can operate as either a Cassegrain telescope (longer focal length, and a narrower field with higher magnification) or a Newtonian telescope (brighter field). They have a pierced primary mirror, a Newtonian focus, and a spider to mount a variety of replaceable secondary mirrors. A new era of telescope making was inaugurated by the Multiple Mirror Telescope (MMT), with a mirror composed of six segments synthesizing a mirror of 4.5 meters diameter. This has now been replaced by a single 6.5m mirror. Its example was followed by ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Research telescopes

Telescopes are broadly classified into two main types. Optical telescopes Radio telescopes Optical telescopes are also divided into two types. Galilean refracting telescopes Newtonian reflecting telescopes Galilean or refracting telescopes employ the refractive properties of light, and are constructed of lenses. These can be used for both terrestrial and astronomical viewing. Newtonian or reflecting telescopes employ the reflect ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Types

No telescope can form a perfect image. Even if a reflecting telescope could have a perfect mirror, or a refracting telescope could have a perfect lens, the effects of aperture diffraction could still not be escaped. In reality, perfect mirrors and perfect lenses do not exist, so image aberrations in addition to aperture diffraction must be taken into account. Image aberrations can be broken down into two main classes, monochromatic, and polychromatic. In 1857, Philipp Ludwig von Seidel (1821-1896) decomposed the first order monochromatic aberrations into five constituent aberrations. They are now common ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Imperfect images

The telescopes are broadly classified into two main categories. Optical telescopes Radio telescopes The optical telescopes are again divided into two Galilean refracting telescopes Newtonian reflecting telescopes The Galilean or refracting telescopes used refraction property of light. They were made up of lenses. They can be used for both terrestrial as well as astronomical viewing. The Newtonian or reflecting telescopes used reflec ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Types

A simple telescope mount is an altitude-azimuth or altazimuth mount. It is similar to that of a surveying transit. A fork rotates in azimuth (in the horizontal plane), and bearings on the tips of the fork allow the telescope to vary in altitude (in a vertical plane). A dobsonian mount is a type of altazimuth mount which has proven to be very popular as it is simple and cheap to make. The major problem with using an altazimuth for astronomy is that both axes must be continuously adjusted to compensate for the Earth ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Telescope mountings

Most large research telescopes can operate as either a cassegrain telescope (longer focal length, and a narrower field with higher magnification) or newtonian telescope (brighter field). They have a pierced primary, a newtonian focus, and a spider to mount a variety of replaceable secondaries. A new era of telescope making was inaugurated by the MMT, with a mirror composed of six segments synthesizing a mirror of 4.5 metres diameter (this has now been replaced by a single 6.5m mirror). Its example was followed by ...

See also:

Telescope, Telescope - History, Telescope - Types, Telescope - Telescope mountings, Telescope - Research telescopes, Telescope - Imperfect images, Telescope - The five Seidel aberrations, Telescope - The chromatic aberrations, Telescope - Famous optical telescopes, Telescope - Related lists

Read more here: » Telescope: Encyclopedia II - Telescope - Research telescopes