Across
- 4. a system of millions or billions stars
- 5. machines; robot
- 7. a person first to explore
- 8. something that happens located in the stars
- 9. no human on board
Down
- 1. an expert in physics
- 2. sailors
- 3. relating to the planet Mars; soemone who lives there
- 6. a craft placed in orbit around earth