A comet is a small member of the solar system made up of rocky material held together by frozen gases. It is like a dirty snowball. The parts of the comet include the halo, the head and the tail. A halo is material that surrounds the nucleus. The head is surrounded by hydrogen gas. The tail consists of two parts. These include the ion tail and the dust tail.

70% to 80% of a comet is made up of gas and water. The 20% to 30% left over is chunks of metal and rocky material. The outer layer of the comet is made of ice but when it passes by the sun it begins to evaporate.

Comets travel around the sun in oval shaped paths. The time it takes can be anywhere from 7 years to millions of year. Astronomers have yet to see a comet that was not in our solar system. They are too small to be seen any farther away.

Some famous comets are: The Great Comet of 1843, The Great Comet of 1884, The Hale-Bopp Comet, Donati's Comet, and the Shoemaker Levy 9 Comet that hit Jupiter in 1994.

 

FUN FACT

When a comet approaches the sun its tail is following. When it moves away from the sun its tail is leading the comet.