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 ?
According to Daniel Green (Harvard University), small satellites around large main-belt asteroids typically have orbits roughly five times larger than their primary's diameter, which here would correspond to about 250 km.
The unmanned craft, set for launch in February 1996, will first journey through the asteroid belt, flying by the main-belt asteroid Iliya in August 1996.
It would identify a wide array of objects beyond mini-moons: imminent Earth impactors, other NEOs, main-belt asteroids, comets, Trojans (objects that share Jupiter's orbit), Centaurs (renegades from the Kuiper Belt), and trans-Neptunian objects.
Students carefully inspect each sub-image with their own eagle eyes to reduce the potential for missing a main-belt asteroid or, on occasion, an NEO.
It's about 230 km (140 miles) wide, making it the largest main-belt asteroid discovered so late and numbered so high.
Most main-belt asteroids are thought to be small bodies that were prevented from accreting into a single body by Jupiter's powerful gravity.
Scheila, a main-belt asteroid, had never been seen as anything but normal since its discovery in 1906.
A year before, in 2005, Peter Thomas (Cornell University) and his colleagues reported Hubble Space Telescope observations showing that the largest main-belt asteroid, Ceres, is almost spherical, which means its interior has differentiated into layers.
People would have to travel for years to get to Mars or a main-belt asteroid and back.
There are 187 main-belt asteroids larger than 100 km in diameter, and 474 that are larger than 50 km.
MBCs are main-belt asteroids situated at a distance of between 2 and 3.