- Distance
- 2.2 – 3.2 AU
- Largest body
- Ceres (940 km)
- Known objects
- > 1 million
- Total mass
- ≈ 3% of the Moon
About Asteroid Belt
The asteroid belt contains millions of rocky bodies, yet their combined mass is only about 3% of the Moon's. Jupiter's gravity prevented them from ever assembling into a planet. Despite films suggesting otherwise, the belt is mostly empty space: spacecraft pass through it without difficulty. Ceres, 940 km across, is the largest object and is classed as a dwarf planet. Vesta, Pallas and Hygiea are the next biggest. Some asteroids are metal-rich, some carbon-rich, and some are loose rubble piles held together by weak gravity.
- Ceres was visited by NASA's Dawn in 2015
- Average spacing between asteroids is about 1 million km
- Source of most meteorites that reach Earth
In pictures
