Comet Hyakutake. Optical image showing the head or coma (bottom left) and the tail of Comet Hyakutake, one of the brightest comets to appear in the sk

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Comet Hyakutake. Optical image showing the head or coma (bottom left) and the tail of Comet Hyakutake, one of the brightest comets to appear in the sky. Comets are bodies, mostly formed by water ice, which orbit the Sun with usually highly elongated orbits. When a comet approaches the Sun the water ice vaporises forming the coma, a cloud of gas and dust which can be up to 15 times the diameter of the Earth, and the tail. Comets have two types of tails: a gas tail (blue) which shows long filaments of excited gases, and a dust tail (not clearly seen here) in which dust particles reflect sunlight. The bright star at centre right is Algol (Beta Persei). North is at centre right.

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Size: 4938px × 3614px
Photo credit: © REV. RONALD ROYER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: 17, 1996, algol, april, astronomy, coma, comet, cometary, cosmology, gas, hyakutake, science, tail