| A | B |
|---|
| Solar System | Sun and its nine plantes |
| revolution | one full orbit around the sun |
| axis | imaginary center line |
| rotation | one whole spin of an object on its axis |
| space probes | space craft that gathers data without a crew |
| comet | a frozen mass that orbits the Sun |
| asteroids | a rocky mass that orbits the Sun |
| meteoroid | small asteroid |
| meteor | a meteoroid that hits Earth's atmosphere |
| meteorite | a meteor that hits the Earth |
| satellite | a moon, rock, or anything that orbits another object |
| moon phases | Shapes of the lit side of the Moon |
| Jupiter | gas planet, largest planet |
| Neptune | deep blue gas planet |
| Saturn | least dense planet, |
| Mars | the red planet |
| Venus | covered in hot clouds |
| Mercury | small rocky planet closest to the sun |
| Uranus | gas planet with the tipped axis |
| Earth | 3/4 water and ice cover it |
| Sun | largest body in the solar sytem |
| Comet Halley | passes by the Sun about every 76 years |
| Asteroid Belt | area between Mars and Jupiter where most asteroids orbit |
| New Moon | You don't see the Moon |
| Full Moon | You see the entire lighted part of the Moon |
| Crescent Moon | a tiny sliver of the moon is lit |
| First Quarter | Half of the Moon's side is lit |
| tides | caused by the Moon's gravity pulling on Earth |
| Earth's tilt on its axis | causes the seasons |
