Formerly the largest known Asteroid, Ceres is now classified as a Dwarf Planet.
- Discovered in 1801 - the first asteroid to be discovered.
- Length of one Revolution about the sun is about 4.6 Earth years.
- Distance from the sun is 2.77 AU.
- Broadest distance/diameter is 914 km or 568 miles.
- Gravity is 0.04 (where Earth's is 1.0).
- Composed of carbonaceous rock .
- No atmosphere.
- Almost two times the size of the next largest known asteroid.
- All newly discovered asteroids receive name and number once observed sufficiently to accurately predict orbit.
- The proper designation, in this case, is "1 Ceres."
- Usually only the name is used.
- Ceres orbits near the middle of the Asteroid Belt.
- Asteroids with orbits closer to the sun are:
- Lighter-colored than Ceres and outer-belt asteroids.
- Composed of silicate minerals and metals like terrestrial rocks.
- From the zone of Ceres outward:
- Asteroids are of a different type, black in color.
- Known as so-called carbonaceous asteroids.
- They are colored by soot-like carbon compounds.
- Carbon compounds condensed in the cold temperatures of those regions.
- Ceres is of the latter type:
- Spectra have shown black, carbonaceous material as well as water of hydration.
- This consists of water molecules trapped in the minerals.
- Water molecules could be driven off easily by heating.
- in 1801 it became the first asteroid discovered due to its large size.
- The next asteroid to be discovered was Pallas:
- Second-largest known at 522 km (324 miles) across.