Across
- 2. observations and expectations that are well explained
- 3. circular looking galaxies
- 7. planets revolving a sun.
- 10. explosion
- 11. large cloud of gas and dust in space
- 14. force
- 15. meter is the ____ ____ of length
Down
- 1. information that supports or refutes a theory
- 4. average distance from sun to earth
- 5. everything
- 6. something with such high gravity that light cannot escape
- 8. the type of galaxy we live in
- 9. the galaxy we are in
- 12. a large unit of length made to calculate the distance between stars
- 13. a collection of stars dust and gases held together by gravitational forces