CH. 30: Stars, Galaxies, and the Universe

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Across
  1. 4. the brightness that a star would have at a distance of 32.6 light-years from Earth
  2. 5. the theory that all matter and energy in the universe was compressed into an extremely small volume that 3 to 15 billion years ago exploded and began expanding in all directions
  3. 10. a collection of stars, dust, and gas bound together by gravity
  4. 11. quasi-stellar radio source; a very luminous object that produces energy at a high rate
  5. 12. a rapidly spinning neutron star that emits pulses of radio and optical energy
  6. 15. one of 88 regions into which the skay has been divided in order to describe the locations of celestial objects; a group of stars organized in a recognizable pattern
  7. 16. the brightness of a star as seen from the Earth
  8. 18. a star that suddenly becomes brighter
  9. 20. an object so massive and dense that even light cannot escape its gravity
Down
  1. 1. a very large and bright star whose hot core has used most of its hydrogen
  2. 2. a large cloud of gas and dust in interstellar space; a region in space where stars are born
  3. 3. radiation uniformly detected from every direction in space; considered a remnant of the big bang
  4. 6. a star that has collapsed under gravity to the point that the electrons and protons have smashed together to form neutrons
  5. 7. a large celestial body that is composed of gas and that emits light
  6. 8. the location on the H-R diagram where most stars lie; it has a diagonal pattern from the lower right to the upper left.
  7. 9. the study of the origin, properties, processes, and evolution of the universe
  8. 13. the distance that light travels in one year
  9. 14. a very large and bright star whose hot core has used most of its hydrogen
  10. 17. an observed change in the frequency of a wave when the source or observer is moving
  11. 19. an apparent shift in the position of an object when viewed from different locations