Unit 3 & 4 Vocab

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Across
  1. 3. A region of space containing a collection of asteroids or objects
  2. 6. Material thrown out by an impact event like a crater formation
  3. 7. A large planet composed mostly of hydrogen and helium
  4. 9. The apparent backward movement of a planet in the sky
  5. 11. When a celestial body keeps the same face toward another
  6. 12. The average distance between Earth and the Sun
  7. 14. A meteoroid that survives its passage through Earth's atmosphere
  8. 17. When the Sun reaches its highest or lowest point in the sky
  9. 18. A celestial object made of ice and dust with a glowing tail
  10. 19. A rocky planet with a solid surface, like Earth
Down
  1. 1. The imaginary plane in which most planets orbit the Sun
  2. 2. A region beyond Neptune that contains icy bodies
  3. 4. The time when day and night are of equal length
  4. 5. A celestial body too small to clear its orbit of debris
  5. 8. A small rocky or metallic body traveling through space
  6. 10. Large, dark basaltic plains on the Moon caused by lava flow
  7. 13. When the Earth blocks sunlight from reaching the Moon
  8. 15. An elongated circle that represents planetary orbits
  9. 16. A measure of how an orbit deviates from a perfect circle