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Comets and Meteors. Comets. Large, icy dirt-ball Contains dust, ice, carbon dioxide, ammonia, methane and more Most comets ~ 16km across. Comets. Comets orbit the sun, but have very large orbits The orbits come from a region beyond Pluto, called the ‘ Oort Cloud’. Comets.
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Comets • Large, icy dirt-ball • Contains dust, ice, carbon dioxide, ammonia, methane and more • Most comets ~ 16km across
Comets • Comets orbit the sun, but have very large orbits • The orbits come from a region beyond Pluto, called the ‘Oort Cloud’
Comets • Scientists think some comets come from a band of icy objects called the “Kuiper belt”, beyond Neptune’s orbit
Comets • Some comets, called ‘sun-grazers’, smash right into the sun or get so close that they break up and evaporate.
Comets • When a comet gets closer to the sun, the ice turns into a gas cloud (called a ‘coma’) • Solar radiation pushes dust from the sun, forming a dust tail • Charged particles convert some of the sun’s gases, forming an ion tail
Comets • Comets leave a trail of debris behind them that can lead to meteor showers on Earth. • Some famous comets: • Haley’s Comet • Comet Hale-Bopp • Comet Shoemaker-Levy • Comet Holmes
Meteors • Meteors (“shooting stars”) are tiny bits of dust and space rocks that fall through the atmosphere. • They heat up so much that they become a fiery streak across the night sky.
Meteors • Meteor showers happen when Earth passes through a region of space that a comet passed through before • During these times, you can see 1-2 shooting stars per minute!
Meteors • Most meteors are the size of a grain of sand • They burn up completely in the atmosphere
Meteors • Upcoming meteor showers: • Geminids, Dec.13 – Dec.14 • Quadrantids, January 3 • Lyrids, April 21 • Eta Aquarids, May 5
Meteors • Meteors that are big enough to make it all the way to the ground are called ‘meteorites’
Meteors • Finding one is a pretty big deal!