Across
- 4. Seventh planet
- 5. Radioactive noble gas
- 7. Argentum
- 9. Relating to the sun
- 11. A group of stars
- 12. Going to collide with the Milky Way
- 14. Moon that is larger than Mercury, and Titan
- 19. The study of chemicals in space
- 20. The form of static electricity in clouds
- 21. NASA sent these missions to the moon
- 23. Aurorae at poles, not Jupiter or Earth
Down
- 1. The thickness of a liquid
- 2. A gas cloud
- 3. Includes chlorine and and iodine
- 6. Heated electromagnetic gas
- 8. Reddest object in the solar system
- 10. A star; biggest in the Orion
- 13. The study of weather
- 15. Includes Lutetium
- 16. The star with 7 Earth sized planets
- 17. Protons and Neutron
- 18. The study of life
- 21. Third Noble gas
- 22. Latin for gold