| Summary: | Asteroids (from Greek, dorp "star" + doo; "like", in form), sometimes grouped with centaurs , Neptune trojans and trans - Neptunian objects into minor planets or planetoids , are a class of small Solar System bodies in orbit around the Sun. The term "asteroid" was historically applied to any astronomical object orbiting the Sun that was not observed to have the characteristics of an active comet or a planet, but it has increasingly come to particularly refer to the small rocky and metallic bodies of the inner Solar System and out to the orbit of Jupiter. As small objects in the outer Solar System have begun to be discovered their observed composition differs from the objects historically termed asteroids Harboring predominantly volatile-based material similar to comets rather than the more familiar rocky or metallic asteroids, they are often distinguished from them.
|
|---|