Across
- 5. a natural or artificial body that revolves around a planet
- 9. a small, rocky object that orbits the sun, usually in a band between the orbit of Jupiter and Mars
- 11. the portion of Earth that is water
- 13. a model for the formation of the solar system in which the sun and planets condense from a cloud (or nebula) of gas and dust
- 15. contains the sun and all of the planets and other bodies that travel around in it
- 17. a accumulation of matter
- 20. the distance that light travels in one year; about 9.5 trillion kilometers
- 21. a large, reddish star late in it's life cycle
Down
- 1. Any of the nine primary bodies that orbit the sun; a similar body that orbits another star
- 2. a large celestial body that is composed of gas and emits light; the sun is a typical star
- 3. a large cloud of dust and gas in interstellar space; a region in space where stars are born or where stars explode at the end of their lives
- 4. a small, hot, dim star that us the leftover center of an old star
- 6. an event in which the shadow of one celestial body falls on another
- 7. a collection of stars, dust and gas bound together by gravity
- 8. a gigantic explosion in which a massive star collapses and throws its outer layers into space; plural supernovae
- 10. one of the highly dense planets nearest to the sun; Mercury, Venus, Earth, and Mars
- 12. a group of stars bound by gravity
- 14. a planet that has a deep, massive atmosphere, such as Jupiter, Saturn, Uranus, or Neptune
- 16. a small body of ice, rock, and cosmic dust loosely packed together that follows an elliptical orbit and that gives off gas and dust in the form of a tail as it passes close to the sun
- 18. the change in the illuminated area of one celestial body as seen from another celestial body;phases of the moon are caused by the position of Earth,the sun,and the moon
- 19. an object so massive and dense that not even light can escape its gravity