Across
- 2. A unit of temperature
- 5. Empty
- 7. opposite of matter
- 8. clock
- 9. light from an object that is going towards us
- 11. A cluster of millions or billions of stars
- 12. 2 poles
- 15. Amount of heat in an object
Down
- 1. interaction of electric currents or fields and magnetic fields.
- 3. Made the universe expand exponentially
- 4. the science of the origin of the universe.
- 6. The length in which light travels in a year
- 10. Infinite density
- 13. allowing estimation of its distance from the earth.
- 14. Measures light