Across
- 4. propel with force
- 7. any celestial body orbiting around a planet or star
- 8. the path of a celestial body in its revolution about another
- 10. the natural satellite of the Earth
- 11. the envelope of gases surrounding any celestial body
- 12. a craft capable of traveling in outer space
- 14. not fit for living
- 15. travel to or penetrate into
- 16. name of our planet
Down
- 1. the force of attraction between all masses in the universe
- 2. of the greatest possible degree, extent, or intensity
- 3. celestial body that revolves around the sun
- 5. everything that exists anywhere
- 6. relating to the sun or utilizing the energies of the sun
- 9. jet engine containing its own propellant and driven by reaction propulsion
- 10. mass that enters earth's atmosphere, becoming incandescent
- 13. a person trained to travel in a spacecraft