The Apollo 10 mission was the fourth human spaceflight mission in the Apollo program and the second to orbit the Moon. Launched on May 18, 1969, the mission was the "dress rehearsal" for the historic Apollo 11 mission that would follow two months later. The mission included the first ever
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Apollo 10 was the fourth human spaceflight in the United States' Apollo program and the second to orbit the Moon. NASA, the mission's operator, described it as a "dress rehearsal" for the first Moon landing. It was designated an "F" mission, intended to test all spacecraft components and procedures short of actual descent and landing.