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Comet Giacobini-Zinner. Optical image of Comet Giacobini-Zinner taken in 1905. The comet was discovered in 1900 by M. Giacobini in France and independ
Comet Giacobini-Zinner. Optical image of Comet Giacobini-Zinner taken in 1905. The comet was discovered in 1900 by M. Giacobini in France and independently rediscovered by E. Zinner in Germany in 1913. It has an orbital period of years. A comet's nucleus is composed of ice and dust. As it nears the Sun some of the ice evaporates as its surface is heated. This gas becomes ionised and is drawn outwards by the solar wind to form a tail which points away from the Sun. The released dust may also form a second tail as it is pushed by radiation pressure. Photographed by Barnard (1857-1923) with the 25-centimetre (10-inch) Bruce telescope at Yerkes Observatory, USA.
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Keywords: .., 10-, 1905, astronomical, astronomy, barnard, bruce, comet, cometary, comets, cosmology, early, giacobini-zinner, image, imagery, photograph, science, zinner-giacobini