- a disk-shaped region on the edge of the solar system that contains masses of ice and icy rock, believed to be the source of comets with orbital periods of less than 200 years.Compare Oort cloud.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- a region of the solar system beyond the orbit of Neptune, some 30–1000 astronomical units from the sun, containing up to one thousand million icy planetesimals or comet nucleiSee also Oort
C20: named after G. P. Kuiper (1905–73), Dutch American astronomer, who proposed it in 1951
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
- A disk-shaped region in the outer solar system lying beyond the orbit of Neptune and extending to a distance of about 50 astronomical units, containing thousands of small, icy celestial bodies. It is believed to be a reservoir for short-period comets (comets that make one complete orbit of the Sun in less than 200 years). The Kuiper belt is named after American astronomer Gerard Kuiper (1905-1973), who first predicted its existence.♦ The bodies populating this region are known as Kuiper belt objects, and unlike the bodies in the Oort cloud they are believed to have originated in situ. There are an estimated 70,000 such objects having diameters of more than 100 km (62 mi). The dwarf planet Pluto and its moons are also found in this region. Compare Oort cloud.
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