A large rocky, metallic and/or gaseous body in orbit around a central star.
A rocky and/or metallic body or collection of bodies in orbit around the Sun that formed early in Solar System history and has changed little since that time. Can also be identified as a planetoid or minor planet.
A natural, solid object, up to 1 m (39 3/8") in size, moving in interplanetary space, not limited to asteroids or objects derived from a larger celestial body.*
A trail of light produced by a meteoroid as it passes through an atmosphere (also called a "shooting star"). Most "shooting stars" observed in the night sky actually result from dust-sized particlest, rather than large objects. However, the biggest objects that fall to Earth may result in large craters, such as Barringer Meteor Crater, on the planet's surface.
A meteoroid that was naturally transported from the celestial body on which it formed to a region beyond that body's gravitational field, and that later collided with the surface of a celestial body larger than itself, such as Earth.* A "fall" is a meteorite that was observed to fall and then collected. A "find" is a meteorite what was not observed to fall but that was recognized by distinct features.
An ice- and- rock-bearing body that travels in a highly elliptical orbit around the Sun. Gas and dust released from the comet as it nears the Sun gives a comet its characteristic tail.