Extraterrestrial puzzle

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Across
  1. 2. -hottest planet in the solar system
  2. 5. -all existing matter and space considered as a whole; the cosmos
  3. 6. -a body that moves around the Sun in the solar system
  4. 7. -cold and desert-like planet
  5. 8. -closest planet to the sun
Down
  1. 1. -the degree of heat present in a substance or object
  2. 3. - fifth planet from the sun
  3. 4. -the force that attracts a body towards the centre of the earth or other planets