Across
- 2. a collection of stars, dust and gas bound together by gravity
- 5. a large cloud of gas and dust in interstellar space
- 8. the actual brightness of a star
- 9. the brightness of a star seen from earth
- 10. a star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons
- 11. a small, hot, dim star that is the left over center of an old sun-like star
- 12. a gigantic explosion in which a massive star collapses and throws its outer layers into space
Down
- 1. a graph that shows the relationship between a star's surface temperature and absolute magnitude
- 3. a measure of how bright a star would be if seen from a standard distance
- 4. the distance that light travels in a year
- 6. space and all the matter and energy in it
- 7. all the frequencies and wavelengths of electromagnetic radiation