Star puzzle

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Across
  1. 3. A ____________ is a device used to split light energy into patterns of colours
  2. 5. Absolute magnitude is the brightness of stars it they were all 33 ly away from earth
  3. 6. The brightness of a star depends on both it's luminosity and it's ________ from the observer
  4. 8. After spending billions of years as a star, A star begins to ____ out
Down
  1. 1. Luminosity is the total amount of ______ produced by a star per second
  2. 2. A star begins with a ______: a massive cloud of interstellar gas and dust
  3. 3. The colour of a star gives an indication of the star's ______ temperature
  4. 4. Apparent magnitude is the brightness of stars in the night sky as the appear from _____
  5. 7. The main sequence of a star begins when the ____ temperature reaches 15 million degrees C