| A | B |
|---|
| Asteroid | A rocky body orbiting the Sun |
| Coma | A cloud of dust and gas that forms around a comet's nucleus due to solar heating |
| Comet | An object that is composed of dust, rock, and ice |
| Density | The mass of a substance for a given volume |
| Gravity | Force of attraction between two objects; holds us on earth |
| Kuiper Belt | A belt-shaped region containing many small icy bodies |
| Long Period Comets | A comet with an orbital period of more than 200 years |
| Nucleus | The solid part of the comet, made of ices and rock |
| Oort Cloud | A huge spherical "cloud" of cometry particles |
| Orbit | The path a planetary body makes as it revolves around the Sun |
| Particle | A tiny quantity of a substance |
| Periodic (Short Period) Comets | A comet with an orbital period of less than 200 years |
| Spectrometer | An instrument used to obtain and record a spectrum of an object |
| Tail | A long trail of dust and gas that extends out from the comet |
