asteroid belt

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asteroid belt

(main belt) The zone near to the plane of the ecliptic and between the orbits of Mars and Jupiter that contains the majority of asteroids, known as main-belt asteroids. The edges are well-defined at distances from the Sun of about 1.7 and 4.0 AU respectively and the orbits are strongly concentrated in the plane of the ecliptic. Even so, the individual asteroids in the main belt are widely spaced. The orbital inclination becomes more scattered on moving through the belt. The average inclination is about 10° and the average eccentricity is 0.15. All the bodies are in direct motion. Occasional collisions between asteroids occur at velocities of about 5 km s–1. See also Kirkwood gaps.

asteroid belt

[′as·tə‚rȯid ‚belt]
(astronomy)
The region between 2.1 and 3.5 astronomical units from the sun where most of the asteroids are found.
References in periodicals archive ?
P/2010 A2 (LINEAR) was designated an MBC but, within a month of being discovered, Hubble Space Telescope images suggested that its tail was generated by dusty gravel-not icy comet-stuff--and that it was the result of a head-on smashup between Main Belt asteroids.
It appears that the asteroidal meteorites show signs of the asteroid belt losing a lot of mass four billion years ago, with the escaped mass beating up on both the surviving main belt asteroids and the Moon at high speeds" said lead author Simone Marchi, who has a joint appointment between two of NASA's Lunar Science Institutes, one at the Southwest Research Institute in Boulder, Colo.
While travelling to the comet Rosetta has performed two fly-bys at main belt asteroids with the scientific objective of providing a global characterization of these asteroids, including the determination of their dynamic properties, surface morphology and composition.