Comet Hale-Bopp. Optical image of comet Hale-Bopp seen amongst silhouetted trees. Both the gas and dust tails of the comet are seen. The gas or \ion\"

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Comet Hale-Bopp. Optical image of comet Hale-Bopp seen amongst silhouetted trees. Both the gas and dust tails of the comet are seen. The gas or \ion\" tail (blue) consists of ionized glowing gas blown away from the comet head by the solar wind. The dust tail (white) consists of grains of dust pushed away from the comet head by the radiation of sunlight. A comet's tail always points away from the Sun. Comets have a nucleus of ice and dust. As they approach the Sun their surface evaporates, releasing a tail that can be millions of kilometres long. Comet Hale-Bopp was discovered on 23 June 1995. Photographed on 4 April 1997 in Finland."

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Size: 3493px × 5197px
Photo credit: © PEKKA PARVIAINEN/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, comet, cometary, cosmology, hale-bopp, science