Optical photograph of Comet Brorsen-Metcalf, taken on September 4, 1989, showing its multiple tail. This was the comet's third appearance in our skies

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Optical photograph of Comet Brorsen-Metcalf, taken on September 4, 1989, showing its multiple tail. This was the comet's third appearance in our skies; it has a period of about 71 years and was first seen in July 1847. A comet is a body of ice and dust, which moves around the Sun on a long, elliptical orbit. As it nears the Sun its surface is heated and some of the ice evaporates. The released gas is ionized by ultraviolet light from the Sun & begins to glow. The gas & dust can form several separate tails. A gas tail consists of ionised gas, swept outwards by the solar wind, whereas the grains of dust in a dust tail are blown outwards by solar radiation pressure.

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Size: 4961px × 4014px
Photo credit: © REV. RONALD ROYER/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: astronomy, brorsen-metcalf, comet, cometary, comets, cosmology, science