Asteroid belt
The wide ring of space between Mars and Jupiter where most known asteroids travel around the Sun.
Between the orbits of Mars and Jupiter lies the asteroid belt, where millions of rocky objects circle the Sun. In films it looks crowded, but in real life it is mostly empty space. The asteroids are usually so far apart that spacecraft have flown through it many times without any trouble. If you could squash every asteroid in the belt together, the result would still be much smaller than our Moon, and about a third of that total would be the dwarf planet Ceres alone.
Why did no planet form here? Scientists think the strong pull of giant Jupiter kept stirring the asteroids up, so they smashed into each other instead of gently sticking together.
The belt matters to meteorite lovers because it is where most meteorites come from. Jupiter's pull nudges some fragments into new orbits that cross Earth's path. The famous Allende meteorite, which fell in Mexico in 1969, and the Winchcombe meteorite, which fell in England in 2021, both began as pieces of asteroids. You cannot see the belt as a band in the sky; its members are scattered and very faint.
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Level: Beginner Ages 7 and up