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单词 Encke, Comet 2P/
释义
Encke, Comet 2P/

Astronomy
  • The comet of shortest known period, 3.3 years, which has been observed at more returns than any other. It also has the smallest aphelion distance of any normal comet, 4.1 au, and can be followed around its entire orbit. It was first seen in 1786 by the French astronomer Pierre François André Méchain (1744–1804), and again by C. L. Herschel in 1795. It was rediscovered twice by J. L. Pons, in 1805 and 1818. The common identity of all four comets was established in 1819 by J. F. Encke, after whom it is now named. Comet Encke has probably occupied its current orbit for several thousand years, losing much of its gas and dust in that time. At most returns it is comparatively faint. The comet is the progenitor of a complex dust stream which produces the Taurid and Beta Taurid meteor showers. It has been suggested that Encke is the largest surviving fragment of a single large object that broke up long ago. Its orbit has a perihelion of 0.34 au, eccentricity 0.85, and inclination 11°.8. The nucleus has an estimated diameter of about 5 km.

    http://cometography.com/pcomets/002p.html Information page at Cometography website.


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