astronomy terminology

4. A massive ball of gas that generates prodigious amounts of energy
7. person who made this crossword
8. a physicist who studies astronomy
12. a small frozen mass that travels around the sun
15. between or among stars
16. a giant ball of gas
17. When the Moon or a planet appears especially close either to another planet or to a bright star.
18. any celestial body orbiting around a planet or star
20. A star ending its life in a huge explosion is called a …
21. of or relating to or associated with the moon

1. a mass that enters earth's atmosphere, becoming incandescent
2. the 3rd planet from the sun
3. of or relating to or caused by gravitation
4. relating to the sun or utilizing the energies of the sun
5. The changing illumination of the Moon (or other body) over time.
6. a dwarf planet
9. A solid body orbiting the Sun that consists of metal and rock.
10. An event that occurs when the shadow of a planet or moon falls upon a second body.
11. a giant planet with a ring of ice particles
13. small extraterrestrial body that hits the earth's atmosphere
14. the second nearest planet to the sun
19. A vast collection of stars, gas, and dust.