Across
- 6. the hot, melted fluid rock that erupts from a volcano
- 7. a scientist who studies the universe and its mysteries.
- 9. the layer of gases that surrounds the body of a planet or moon.
- 10. the force of attraction where two or more bodies are drawn.
Down
- 1. a group of stars to which specific names have been given.
- 2. space and everything in it including our Solar System, the stars and all the galaxies.
- 3. a small vent or crack in the surface of a planet or moon from where liquid or gases eject upwards.
- 4. the measure of a straight line passing from side to side of a body, through its center.
- 5. a system of stars held together by gravity and separate from other systems by large areas of space.
- 8. a cloud of gases and dust where stars and planets are formed.