| A | B |
|---|
| axis | the imaginary line through the center of Earth |
| rotation | the spinning of Earth on its axis |
| revolution | the movement of Earth one time around the sun |
| moon phases | the different shapes the moon seems to have in the sky when it is observed from the Earth |
| lunar cycle | the pattern of phases of the moon |
| lunar eclipse | an event in which Earth blocks sunlight from reaching the moon |
| solar eclipse | an event that occurs when the moon blocks the sunlight from reaching the Earth |
| planet | a large body of rock or gas in space |
| orbit | the path a planet takes as it revolves around the sun |
| solar system | the sun, the planets, and their moons |
| star | a hot ball of glowing gases that gives off energy |
| constellation | a group of stars that appear to form the shape of an animal, a person, or an object |
| 1 year/365 days | the amount of time it takes Earth to REVOLVE around the sun |
| four seasons | winter, spring, summer, and fall |
| summer | when the sun's rays strike Earth directly |
| winter | when the sun's rays strike earth at the greatest slant |
| 1 day/ 24 hours | the amount of time it takes Earth to ROTATE once |
| 29 days | the amount of time it takes the moon to go through its phases (the lunar cycle) |
| nine | the number of planets in the solar system |
| the inner planets | Venus, Mercury, Earth, & Mars |
| the outer planets | Jupiter, Saturn, Uranus, Neptune, & Pluto |
