A two-stage version of the Saturn I rocket was launched for the first time.

The test flight, known as Saturn-Apollo 5, was the first orbital mission of the Apollo space program due to improvements to the rocket’s first stage and the addition of the second stage. The first stage’s improvements included enlarged fuel tanks, which allowed it to carry the planned 750,000 lb (340,000 kg) of rocket fuel, and extra fins to increase stability. This test launch showed the world that the US was capable of creating rockets as large as the Soviet Union’s.

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