The Age of Comets

The article summarized below is from THE NATIONAL GEOGRAPHIC (issue Dec.97) by William R. Newcott. It tells about how comets are important and their effect on earth and its people.<br><br>Comets are leftover scrubs of material that did not make it to planethood in the events creating our solar system. They orbit in a perpetual Deepfreeze until some subtle gravitational nudge upsets the delicate balance. The Great Falls begins. First a snowball drifts towards the sun and steadily accelerates. As solar radiation heats the comets the ice within sublimates, escaping as gas from vents from the surface. Sometimes jets of sublimating ice whirl off the rotating comet nucleus like a firework pinwheel. Dust trapped in the ice breaks free. Pushed back by the pressure of the sun's radiation, the dust streams out behind the comet in what appears as a fairytale. The comet is among the fastest thing in the solar system.<br><br>The most important new results are that the comet contains carbon compounds with trace of nitrogen sodium and sulfur. These ingredients are essential for life on earth. That is why scientist believes that a comet might have crushed on earth and from that moment life began. The ion tales are believed to be a kind of wind sock for the solar wind and NASA scientists are hoping to use it to get weather reports from distant solar system.<br><br>Most comets can be only seen with a telescope but every once in a while an impressive one is visible to the naked eye. People through out history gave importance to comets. For example the Romans made a coin about a comet orbiting the sun that shows how its tail points away from the sun. The Babylonians recorded a comet sighting. One of the Astic leaders gave up his land to the Spanish upon seeing a comet.<br><br>Definitely we are living in the age of comets where scientists detect it through telescopes and e-mail it to the central bureau for Astronomical Telegrams in Cambridge Massachusetts USA. Some people even cheat