| A | B |
|---|
| STAR | glowing ball of hot gas that makes its own energy and light |
| PLANET | large object in space that orbits a star such as the sun |
| MOON | natural satellite that orbits a planet |
| SOLAR SYSTEM | a star, such as the sun, and all of the objects that revolve around it in space |
| FUSION | process by which particles combine to form a new particle |
| GALAXY | group of millions of stars |
| ATMOSPHERE | envelope of gas surrounding an object in space |
| SUNSPOT | dark area on the sun's surface that gives off less energy than the rest of the sun |
| GREENHOUSE EFFECT | warming of the atmosphere because of trapped heat energy from the sun |
| ASTEROID | rocky object, smaller than a planet, that orbits a star |
| ASTEROID BELT | region between Mars and Jupiter where most asteroids orbit the sun |
| METEOR | brief streak of light seen when an asteroid enters the earth's atmosphere and burns up |
| METEORITE | asteroid that hits the surface of a planet or moon after traveling through space |
| COMET | ball of ice, rock, frozen gases, and dust that orbits the sun |
| SATELLITE | An object that orbits something else. |
| ORBIT | To circle around something. |
