Some details about Comets and Meteors and meteorites

Comets

                Comets are very small sized celestial bodies. They revolve around the sun highly elliptical orbits. They become visible from the earth only when they come to the sun. A comet has a distinct head and a glowing tail away from the sun. Many comets break up into smaller pieces while approaching the sun.

Important comets and their features 

             Many comets are known to appear again and again after a definite period of time. Enck's comet has the shortest known period about 3.3 years. The period of Hale-Bopp is about 4000 years and the period of kohoutek's is about 785,000 years. Halley's comet and comet 1884 I (Pons-Brooks) are quite bright. Halley's comet appears after nearly 76 years. Halley's comet was last seen in 1986. It may reappear in 2062.

               Astronomers found out on July 8th 1992 Shoemaker-levy, at 43,000 km from Jupiter, close enough for the immense tidal forces created by gravity to pull the comet and break it into 21 fragments which finally plunged into Jupiter. 

Meteors and meteorites

               Meteors are known as shooting stars. We can see a meteor on clear moonless light. Meteors are not stars. Meteors are very small pieces of rocks or metals. Meteors are formed due to breakage of comets, when they pass very close to the sun. When a meteor enters the atmosphere of the earth, it gets heated due to friction of air. Due to the high heat, the meteor begins to glow and evaporates within a short time. Therefore, the path of the meteors appear as a streak of light in the night sky.

               Part of large meteors reaches the surface of earth before they get evaporated completely. These are known as meteorites. Meteorites help the scientists to study the nature of the material of celestial bodies which are of the solar system.