Across
- 3. a galaxy in which the stars and gas clouds are concentrated
- 5. the forse that causes objects with mass to attract one another
- 7. a state of matter with indefinite volume and shape
- 10. a star and the group of planets and other celestial bodies that are held by its gravitational attraction and revolved around it
- 11. Theory that says the universe began as a small point that expanded rapidly about 13.7 billion years ago
- 12. a spiral galaxy with a central bar shaped structure composed of stars
Down
- 1. type of radiation including visable light
- 2. a large grouping of stars in space
- 4. a unit of astromonical distance equivalent to the distance that light tracels in one year
- 6. a displacement of the spectrum of a celestial body toward longer wavelengths
- 8. tiny particles of matter floating in space
- 9. cloud of gas and dust in outerspace