Across
- 2. The name given to the first four outer planets: Jupiter, Saturn, Uranus, and Neptune
- 5. the distance light travels in one year
- 6. matter that does not give off electromagnetic radiation but is quite abundant in the universe.
- 7. a celestial body resembling a small planet but lacking certain technical criteria that are required for it to be classed as such.
- 8. The study of the moon, stars, and other objects in space
- 12. Any system of objects, such as a star system or a galaxy, that is held together by gravity.
- 13. a mixture of gases that surrounds a planet or moon
Down
- 1. Space and all the matter and energy in it.
- 2. No definite shape or volume
- 3. Environments given to production and unstable growths
- 4. An object in space whose gravity is so strong not even light can escape
- 9. A large spiral galaxy that is home to Earth and the rest of our solar system, and about a trillion stars.
- 10. sun, planets, and all the other objects around the sun.
- 11. A fixed luminous point in the night sky that is a large, remote incandescent body like the sun.