Across
- 1. a system of millions and billions of stars
- 3. oldest microwaves
- 4. made up of all matter and space
- 6. a subatomic particle of a class that is thought to bind quarks together.
- 8. the spectrum used to study light
- 10. the expansion of the universe
Down
- 2. what all matter is composed of
- 5. one of the first elements
- 7. the force that attracts a body to a another body
- 9. a massive self-luminous body of gas that shines