Hint: Space
The answer to this puzzle is:
1. NEPTUNE
2. DUST
3. PULSAR
4. CELESTIAL
5. LUNAR
6. CRATER
7. JUPITER
8. PLUTO
9. LIGHTYEAR
10. METEOR
11. MERCURY
12. GALAXY
2. DUST
3. PULSAR
4. CELESTIAL
5. LUNAR
6. CRATER
7. JUPITER
8. PLUTO
9. LIGHTYEAR
10. METEOR
11. MERCURY
12. GALAXY