Across
- 3. Hypothesis about how a Mars sized planet hit Earth, causing a chunk to break off and become our moon.
- 5. Pilot of lunar landing module.
- 7. Peace Corps medical officer turned astronaut.
- 8. Large, flat land area, or plain on the surface of the moon.
- 10. 1st American to orbit Earth.
Down
- 1. Gases almost completely absent from the atmosphere.
- 2. The moon was orbiting the sun and was pulled by Earth into its orbit.
- 4. Nebular cloud + gravity pulled particles together forming the moon.
- 6. The 1st astronaut down the ladder on the moon.
- 9. A long, narrow valley that runs along the lunar surface.