Comets Essay -- Astronomy Essays Space Outer

CometsHave you ever looked up in the sky and seen a little cluster creeping by?If so, did you wonder what it was? That little b every last(predicate) is called a comet. Cometsare small, fragile, and irregularly shaped. Most are composed of frozen gas.However, some are composed of frozen gas and non-volatile grains. They usuallyfollow rattling strict paths around the sun. Comets become most visible when theycross the sun. This also applies to people who view comets with telescopes.When a comet gets near the sun it becomes very visible because the suns radioactivity starts to sublime its volatile gases, which, in turn, blow away smallbits of the little solid material the comet has.Another feature of a comet is a coherent bob. This is caused by materialsbreaking off and expanding. They expand into an enormous escaping atmospherecalled the coma. This becomes at least the size of our planet. With the cometgoing so fast, these materials are forced behind the comet, forming a long tailo f dust and gas.Comets are cold bodies. We see them only because the gases they arecomposed of glow in the sunlight. All comets are regular family members of thesolar dodge family. They are bound by gravity to a strict path around thesolar system. Scientists believe that all comets were formed of material,originally in the satellite part of the solar system, which did not becomeincorporated into planets. This material is from when the planets just startedforming. This makes comets an extremely interesting topic to scientists who arestudying the history of the solar system.In comparison to planets, comets are very small. They can be anywherefrom 750 meters (or less) to 20 kilometers in diameter. However, lately,scientists have been finding proof that there are comets 300 kilometers indiameter or greater.Comets are still compared to the planets, though. Planets usuallyfollow the shape of a sphere. Most planets are fat at the equator. Comets comein all different shapes and sizes. Most evidence that science has revealed saysthat comets are extremely fragile. A comet is so poorly structured that it islike a loose snowball--it can be pulled apart with ones own bare hands.Comets have very awkward rotation periods. They are very oblong. Whencomets reach their aphelion they are usually near Jupiter or sluice sometimesNe... ... is expected to reach its closed point to thesun. At this time it will also be most visible because the sun reflects off thetail of the comet.It will come .914 astronomical units from the sun. This is not allthat close to the sun considering the fact that some comets have run into thesun and others have skimmed the muster of it.Although the comet will be closest to the sun on April 1, it will beclosest to the earth on March 23, 1997. Some people have been motto that thecomet will hit earth and cause human extinction, just like the dinosaurs. Thefact is, however, THE COMET WILL NOT HIT EARTH. The closest it will come is one hundred twentymill ion miles away from the earth.Some people are saying that the comet is going to Be huge, and otherssay it will be small. We will never know though because we can not see thenucleus of a comet. The part of the comet we see is the tail. The tail of acomet can be over 10,000 kilometers long.In all, comets, the history of comets, and comets time lag to bediscovered is very interesting. I think that one day we will get to see thenucleus of a comet, and be able to suck comets form in the Oort Cloud.