Astronomy Week 1

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Across
  1. 1. the celestial firmament
  2. 4. transparent substance used to change the convergence of light
  3. 7. dealing with the phenomena of visible and invisible light
  4. 8. changing the direction of light
  5. 9. casting back a light to show an image
  6. 10. a grouping of stars with a name
Down
  1. 1. a natural body that revolves around a planet
  2. 2. the boundary between the earth and sky
  3. 3. optical instrument used to make distant objects appear larger
  4. 5. a position on a line from one point to another
  5. 6. polished metal or glass with a metallic backing; reflects light