Vesta and Ceres are the two most massive objects in the main asteroid belt.

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Although downward-looking diagrams of the Main Asteroid Belt make it look incredibly dense, the region has significant gaps, clumps and clusters.

FORBES: Main Asteroid Belt No Remnant Of Exploded Planet

They are believed to have broken away from the main asteroid belt between Mars and Jupiter and are our nearest neighbours in space after the Moon.

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Abell says the best estimates now are that the Russian object was initially a rocky silicate asteroid that almost certainly originated from the main asteroid belt.

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But astronomers have been unable to figure out how they get from the main asteroid belt between Mars and Jupiter to the vicinity of the Earth.

ECONOMIST: Celestial mechanics

T. and an expert on the Main Asteroid Belt, points out, the belt could have never hosted a planet large enough to claim Mars as a satellite.

FORBES: Main Asteroid Belt No Remnant Of Exploded Planet

The inner main-belt asteroid 5806 Archieroy was named after Professor Roy shortly after its discovery in 1986.

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Critically, the Baptistina family of asteroids - those that were formed when the larger asteroid destructively entered the main belt - were only formed around 80 million years ago.

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The main source of meteorites, Chinese folklore notwithstanding, is the asteroid belt between Mars and Jupiter, a rough-and-tumble region of our solar system in which would-be planets are upset by Jovian gravity.

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Scientists believe it would take an asteroid around 10 million years to travel from the main belt to Earth, so "this doesn't give a Baptistina fragment much time to get into a suitable position", said Dr Mainzer.

BBC: Asteroid thought to kill dinosaurs may not be guilty