Across
- 4. rocky leftovers from formation of solar system
- 6. planet farthest from sun
- 7. gas and ice giant planets
- 9. cloud of gas and dust that was the start of the solar system
- 10. these are moving away from us at increasing speed, according to Hubble
Down
- 1. nuclear ___________ describes combining two Hydrogen atoms creating light and heat energy
- 2. planet closest to sun
- 3. natural satellite that orbits a planet
- 5. terrestrial, or earthlike planets
- 8. one theory of its creation is the Big Bang