Comets! Comets! Bri Larkin Science Period 1
What Are Comets? • Comets are the largest thing in our solar system! • They’re made up of a mixture of ice and rocks that release gas or dust into the atmosphere. + =
Parts of a Comet • There are three main parts of the comet: -Nucleus -Coma -Tail The nucleus of a comet can range in size from about 100 meters to 40 km! That’s the length of about 240 city blocks!! Tail Coma Nucleus
How Do Comets Glow? • Most Comets are too small to be seen without a telescope! • But sometimes a comet can be seen with the naked eye while it passes for several weeks over the sun • We are able to see comets because of the dust and gas in their Tails and Comas that reflect sunlight! • The glowing effect of the comet is caused by the released gas which contains energy that has been absorbed from the sun. How Are We Able To See Comets From Earth?
How did Comets get their name? Comet • The word “Comets” comes from the Latin word “cometes” which is an earlier form of Ancient Greek. • The Greek word “kome” is Greek for “hair of the head.” • From there Aristotle then named it “kometes” which means “stars with hair.”
Who was the First Person To Discover the Comet? • Comets have been known to man kind for many centuries. • Therefore there isn’t one individual person known who first discovered Comets. • But we do know Edmund Halley founded Halley’s Comet in 1705 • Also, in 1847 Maria Mitchell was the first person to discover a new comet through a telescope.
How Fast do Comets Travel? • A comet’s furthest point from the Sun is Neptune. So, when a comet is far out, away from the Sun, it moves very slowly. (about the speed of an airplane) • But, by the time a comet passes by Earth it travels at a speed of about 40 miles per second!
How Many Comets Have Been Discovered So Far? • As of November of 2005 2,857 comets have been discovered by astronomers. -Scientists predict only 253 will ever return, due to comets crashing into the Sun, and leaving the Solar System entirely.
What Would Happen If a Comet Hit the Earth? • If a comet happened to hit the Earth, many scientists believe it would cause major damage. • Astronomers also predict the extinction of dinosaurs could be caused by a comet that hit the Earth.
How are Comets Named? • Comets are usually named after their original discoverer. • An example of this is Halley’s Comet which was founded by Edmund Halley.
How Big Can a Comet Get? • A comet’s nucleus usually forms up to about 50 miles. • Once they reach the inner solar system the ice turns to gas. • The gas then stretches a comet’s tail out for millions and millions of miles.
Interesting Facts • Comets are commonly called “dirty snowballs!” • Halley’s Comet becomes visible every 76 years! It’s next appearance should be in 2061! • Before scientists knew exactly what comets were, many people in ancient times thought comets were a sign of bad luck and misfortune • Halley’s Comet is the most famous comet of all!
Pictures Comet Lulin Comet West Halley’s Comet Also Comet Lulin
Thanks For Watching! -Shoot for the Moon. Even if you miss, you’ll land among the stars! Thank You!
Bibliography • http://www.nasa.gov/worldbook/comet_worldbook.html • http://www.kidseclipse.com/pages/a1b3c0d3.htm • http://www.universetoday.com/40733/parts-of-a-comet/ • http://www.windows2universe.org/comets/comet_il.html • http://en.wikibooks.org/wiki/Wikijunior:Solar_System/Comets • http://www.newton.dep.anl.gov/askasci/ast99/ast99101.htm • http://nineplanets.org/comets.html