Exploratour - Evolution of the Solar System
More than 100,000 asteroids lie in a belt between Mars and Jupiter. These asteroids lie in a location in the solar system where there seems to be a jump in the spacing between the planets. Scientists think that this debris may be among those which potentially may have formed a planet, but were prevented from doing so by the immense gravity of Jupiter.
Asteroids are small rocky objects with round or irregular shapes which can be up to several hundred km across.
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