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Space Probes to the Planets
Unit 5, story 5
the air that surrounds the earth
holes in the ground shaped like bowls
spacecraft carrying scientific recording instruments
a vehicle used for flight in outer space
any of the thousands of small planetary bodies that revolve around the sun (chall.)
unclear; clouded (chall.)
masses of stone or metal that have reached the earth from outer space (chall.)
fallen meteors (chall.)
the sun and all the planets and comets that revolve around it (chall.)