HR Diagram

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Across
  1. 3. The heat intensity of a planet
  2. 5. Hot and dim planets
  3. 7. A system of stars
  4. 8. Brightness of a planet
  5. 9. The ____ of stars
Down
  1. 1. Middle-aged planets
  2. 2. Used to determine the luminosity and temperature of a planet
  3. 4. All stars have different points in their ____ _____
  4. 6. Average temperature and brightness
  5. 9. Betelgeuse belong in this section