Across
- 1. An invisible force that pulls things toward each other
- 6. The process by which two or more small nuclei fuse to make a bigger nucleus
- 9. The distance that light travels in one year
- 11. All of space and everything in it
- 12. Particles found within the atom, mainly protons, neutrons, and electrons.
- 14. Super hot glowing ball of gas that makes its own light
Down
- 2. The average distance between the earth and the sun
- 3. Tiny particle with no charge
- 4. A large cloud of dust and gas in space
- 5. A collection of stars, dust, and gas bound together by gravity
- 7. Smallest particle of an element
- 8. A state of matter that starts as a gas and then becomes charged.
- 10. A pure substance made of only one kind of atom
- 13. Positively charged subatomic particle