| A | B |
|---|
| solar system | A star and all the planets and other objects that revolve around it. |
| planet | A large body that arevolves around a star. |
| asteriod | a small rocky object that moves around the sun |
| comet | A ball of rock, ice, and frozen gases that revolves around the sun. |
| star | huge ball of superheated gases |
| satellite | An object that moves around another object in space. |
| orbit | the closed path of one object in space around another object |
| revolve | to travel in a closed path |
| axis | An imaginary line that runs through the center of Earth from the North Pole to the South Pole |
| rotate | to spin around an axis |
| telescope | a tool that makes far away objects look larger and closer |
| day | the length of time it takes a planet to spin around once on its axis |
| moon | A natural body that revolves around a planet. |
| season | one of four parts of the year; spring, summer, fall, and winter. The tilt of the Earth and the constant movement around the sun causes the seasons. |
| year | the length of time it takes a planet to orbit the sun |
| phase | One of the shapes the moon seems to have as it orbits Earth. |
| waxing | the moon's phases get bigger |
| waning | the moon's phases get smaller |
| reflect | to bounce off; as light |
| constellation | A pattern of stars that form an imaginary picture or design in the sky. |
| sun | the star at the center of the solar system |
| galaxy | A huge system of gases, dust, and many stars. |
| universe | Everything that exists in space. |
