Across
- 4. a very large star of high luminosity.
- 5. two stars and one revolves around another.
- 6. a group of stars forming a pattern.
- 10. a small very dense star.
- 12. a contracting mass of gas.
- 13. stars a celestial object of very small radius.
Down
- 1. a cloud of gas and dust in outer space.
- 2. a group of similar things.
- 3. a system of billions or millions of stars.
- 5. from the earliest known periods.
- 7. a star that is even bigger than a giant.
- 8. the distance that light travels in one year.
- 9. to be a rotating neutron star.
- 11. a star that suddenly increases greatly.
- 14. having a sudden large increase in brightness.