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