| A | B |
|---|
| minor planets | look like stars rather than planets |
| asteroids | means starlike |
| asteroids found between what planets | mars and jupiter |
| Icarus | passes very close to the sun |
| comets | visible without a telescope |
| Tycho Brahe | comet is 6 times as far away as the moon |
| Kepler | believed comets moved in a straight line |
| two main parts of a comet | head and tail |
| two main parts of head | nucleus and coma |
| ices | consist of rocks, dust and fozen material |
| type I tail | mainly gas and straight, forms quickly |
| type II tail | mainly dust and curved, forms slowly |
| characteristic of tail | tail always points away from the sun |
| when does a comet have no tail? | when it is far away from the sun |
| Halley's comet | period of 75 years |
| meteoroid | particle of rock or dust in space orbit around sun |
| meteor | when meteoroid is in the earth's atmosphere and glows |
| bolide | when meteor explodes in atmosphere |
| meteorite | when a meteor lands on the ground |
| sporadic meteors | meteors seen coming in random direction |
| shower meteors | meteors in concentration as earth moves into a field of meteors |
| stones or stony | most common meteorite |
| Irons | second most common meteorite |
| Stony-irons | rare meteorite |
| Barringer Meteorite crater | found in Arizona about 4000ft across |
| Tunguska event | occur in Siberia, believed to be a comet |
