Across
- 5. Scientists who study space
- 6. The process that combines atoms and releases energy.
- 7. The distance that light can travel in one year.
Down
- 1. A group of stars that form a pattern
- 2. Includes planets, moons, asteroids, and comets.
- 3. A large group of stars, planets, gas, and dust stuck together by gravity.
- 4. The type of light that carries more energy than visible light