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 ?
"These bodies [NEAs] may provide the missing links between meteorites, comets, and main-belt asteroids," Binzel says.
"Some of its centimeter-sized samples contain totally different kinds of meteorites from very different main-belt asteroids. We still don't understand how it acquired them."
Working with scientists, HOU high-school students began discovering main-belt asteroids. Remarkably, students also discovered a Kuiper Belt object (KBO).
Most main-belt asteroids are thought to be small bodies that were prevented from accreting into a single body by Jupiter's powerful gravity.
Small main-belt asteroids are of keen interest because they have a relatively high probability of being kicked into an Earth-crossing orbit.
"All other large main-belt asteroids with one or more moons are very porous," said Emery.
Such a population would be several hundred times the estimated number of main-belt asteroids in that size range.
No space agency will ever spend what it would take to get closeups of a great many minor bodies of the solar system, from near-Earth objects to main-belt asteroids to comet nuclei, Trojans, Centaurs, and Kuiper Belt objects.
'Ordinary' main-belt asteroids will never be quite the same again, and we should now consider initiating a Section monitoring programme of say the 1000 brightest asteroids to see whether other such events can be detected in years to come.
We have never visited any of the icy Trojans and Centaurs, populations roughly as numerous as the main-belt asteroids. Finally, missions like Rosetta and Hayabusa have shown us the dynamic nature of the solar system's tiniest bodies, and we'll likely never finish our reconnaissance of all those.
There are 187 main-belt asteroids larger than 100km in diameter, and 474 that are larger than 50km.
At first glance, that identification wouldn't seem to link meteorites with main-belt asteroids, since (3103) 1982BB does not now reside in the belt.