Are objects made up of gas, ice and dust. They travel around the Sun in an orbit.
Are warmed up as they approach the Sun. This causes the Comet to form a head and tail. The head is the cloud-like mass we see in the front. The tail is the trailing part which is made up of small particles and ice.
Lose mass each time they pass through the inner regions of the Solar System.
Are usually named after the person who discovered them.
Halley's Comet (above) and Hale-Bopp Comet (right) are two famous comets.