Across
- 4. A person who travels to outer space
- 6. A cloud of gas and dust in space
- 7. The force that pulls objects toward each other
- 8. Russian term for a space traveler
- 11. An object orbiting a planet or star
Down
- 1. The platform from which rockets are launched
- 2. A massive system of stars bound by gravity
- 3. A vehicle that propels spacecraft into orbit
- 5. An instrument used to observe distant celestial objects
- 9. The curved path around a celestial body
- 10. The red planet explored by rovers
- 12. A small rocky body orbiting the sun