Across
- 4. Mercury Venus Earth Mars
- 6. the shifting of wavelengths to the red part of the spectrum
- 7. Jupiter Saturn Uranus Neptune
- 8. first element to form 300,000 years after the Big Bang
- 10. the distance light travels in one year
- 11. force that powers the Sun and all other stars in the galaxy
Down
- 1. small dense sphere containing everything in the universe
- 2. this particle makes protons and neutrons
- 3. the 2nd most abundant element in the universe
- 5. leftover radiation from the explosion, also called thermal energy
- 9. theory that explains the origin of the universe