1. Comets, Asteroids, and Meteoroids Section 20.5

2. Comets Loose collections of ice, dust, and small rocky particles whose orbits are usually very long, narrow ellipses Comet head is made of a solid inner core (nucleus) and a fuzzy outer layer (coma)

3. Comets The coma forms when gases are released due to getting close to the sun A comets tail is caused by gases streaming away from the sun Head Tail

4. Comets Comets originate from the Kuiper belt (outside of Neptune) or the Oort cloud (surrounds the solar system)

5. Asteroids Rocky objects that are too small and numerous to be considered planets Most orbit between Mars and Jupiter (asteroid belt) One hit Earth 65 million years ago One could hit again

6. Meteors Meteoroid – chunk of rock or dust in space Meteor – a meteoroid that is burning up in Earth’s atmosphere Meteorite – a meteor that doesn’t completely burn up and hits the ground