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8 asteroids in our solar system

By: Katherine Butler on May 24, 2012, 7:18 p.m.

Photo: NASA, ESA, J.-Y. Li (University of Maryland) and G. Bacon (STScI)

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Dwarf planet, asteroid or both?

It may look like a simple round object, but Ceres is anything but. In 2006, it was classified as a dwarf planet with a lot of ice below its surface. A dwarf planet means that the object orbits around the sun and is large enough to have its own gravity to make it a sphere; however, its gravity is not strong enough to clear its own orbit. This means that it does not suck smaller objects into itself or throw them out of orbit. Ceres was upgraded when Pluto was downgraded from planet to dwarf planet. Ceres is 605 miles across and orbits the sun once every 4.6 years.