Across
- 3. "fuel" of the stars
- 4. inner part of a sunspot
- 9. gas planets, rings and many moons
- 12. spinning of Earth on its axis
- 13. outer part of a sunspot
- 14. constant for all types of EM waves
- 15. Shape of a planet's orbit
- 16. Sun rises on this horizon
- 17. Sun in the center of the universe
- 18. darker in appearance and younger region on the Moon
Down
- 1. Besides our Sun, brightest star in the sky
- 2. planets with no rings and rocky terrain
- 5. reddish layer of the Sun
- 6. only visible during a total solar eclipse
- 7. universe expanding from a single point
- 8. Earth's sister planet
- 10. first rock from the sun
- 11. Sun sets on this horizon