Across
- 4. A collection of stars, dust, and gas bound together by gravity.
- 7. A measure of how bright a star would be if seen from a standard distance.
- 9. The distance that travels in a year;about 9.46 trillion kilometers.
- 11. A gigantic explosion in which a massive star collapses and throws its layers into space.
- 12. Hertzsprung-Russell diagram a graph that shows the relationship between a star's surface temperature and absolute magnitude.
Down
- 1. All of the frequencies or wavelengths of electromagnetic radiation.
- 2. The brightness of a star seen from Earth.
- 3. A small hot dim star that is left over center of an old sun like star.
- 5. The actual brightness of a object such as a star.
- 6. A star where it has collapsed under gravity to the point that electrons and protons have smashed together to form neutrons.
- 8. A large cloud of gas and dust in interstellar space;a region where stars are born.
- 10. Space and all the matter and energy in it.