| A | B |
|---|
| gravity | A force that pulls objects toward each other. |
| asteroid | A small rocky object that revolves around the sun. |
| solar system | A star and all the objects that orbit around it. |
| orbit | The path of an object as it moves around another object. |
| galaxy | A huge group of stars held together by gravity. |
| phase | Each change the moon's shape seems to have as it revolves around the Earth. |
| comet | A ball of dust, ice, rocks, and frozen gases that revolves around the sun. |
| revolution | The movement of an object around another. |
| satellite | An object in space that revolves around a larger body. |
| rotation | The turning of an object on its axis. |
