Across
- 2. Explains how universe developed from very tiny, dense “singularity”.
- 5. If stars move toward Earth, light becomes brighter.
- 7. It includes all of space, and all the matter and energy that space contains.
- 12. Low temp waves indicating explosion occurred.
- 13. ____________ increases = Frequency decreases.
- 16. Equal _________ are swept out in equal amount of time.
- 17. Proposed that the Universe is expanding.
- 18. A large cluster of galaxies.
- 19. Stars are moving away from Earth and their light becomes dimmer.
- 20. Change in frequency of waves moving relative to its source.
Down
- 1. Responsible for movement of dust clouds to form planets and stars.
- 3. Galaxies that often appear reddish because they contain many old stars.
- 4. Planets move ________ when closest to Sun and slowest when farthest from Sun.
- 6. Galaxies that often appear bluish because they contain many young stars.
- 8. Solar System formed from huge, rotating cloud disk of dust and gases.
- 9. Proposed the three Laws of Planetary Motion.
- 10. Is a system of stars, stellar remnants, interstellar gas, dust, and dark matter bound together by gravity.
- 11. A star with the group of heavenly bodies that revolve around it.
- 14. Orbit of every planet is an _________ with Sun at one foci (focus).
- 15. The brightest object in our sky (besides the sun and the moon) is ________.