| coma |
A coma is the roughly spherical blob of gas that surrounds the nucleus of a comet. The coma is comprised of water vapor, carbon dioxide gas, and other neutral gases that are given off by the solid nucleus. The coma and the nucleus form the head of a comet.
Ãâó: www.ccastronomy.org/terminology.htm
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| coma |
associated mainly with parabolic reflector telescopes which affect the off-axis images and are more pronounced near the edges of the field of view. The images seen produce a V-shaped appearance. The faster the focal ratio, the more coma that will be seen near the edge although the center of the field (approximately a circle, which in mm is the square of the focal ratio) will still be coma-free in well-designed and manufactured instruments.
Ãâó: www.astrostuff.com/OPTICAL_TERMS.htm
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| coma |
An off-axis aberration that results in blurry star images near the edge of the field of view. It is most common in fast f-ratio reflecting telescopes. Parabolic Mirror: A parabolic or more accurately a
Ãâó: www.peekr.ca/glossary.htm
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