The Command Module
Initially, the three astronauts were scheduled to carry out a mission in high-earth orbit only. But because of production delays, their flight plan was changed. Anxious to stay ahead in the space race, NASA green-lighted a journey to the moon's orbit, and its engineers scrambled to adapt the mission protocols to lunar duty. In the above photo, NASA scientists evaluate the Command/Service Module, or CSM, which would now be used to carry the astronauts to the moon and back.

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