The Big Bang
Across
- 3. a collection of stars planets and other matter held together by gravity
- 4. most abundant element in the universe
- 7. our galaxy
- 8. balls of gas that produce light and heat energy
- 10. everything that exists
- 12. leftover heat from the big bang
- 13. galaxies that show _______ are moving away from us
Down
- 1. did not exist before the big bang
- 2. the theory that masses apply a force of attraction on other masses
- 5. the effect observed when an ambulance drives away from you
- 6. the further away a galaxy is the ______ it is said to be moving
- 9. shown by galaxies moving towards us
- 11. scientist who observed that the Universe was expanding
- 14. the Universe may end in a big ______