How Did Apollo 8 Become the First to Travel Around the Moon?

earthrise-02 — This photo of 'Earthrise' over the lunar horizon was taken by the Apollo 8 crew in December 1968, showing Earth for the first time as it appears from deep space. (Image credit: NASA)

Apollo 8 was the first manned mission to orbit the moon and marked the beginning of a new era in man’s exploration of space.

Apollo 8 was launched on Dec. 21, 1968. Astronauts Col. Frank Borman, the commander; Capt. James A. Lovell, Jr., the command module pilot; and Major William A. Anders, the lunar module pilot, were on their way to the Moon. The crew spent seven days in space, returning Christmas day. They were the first people to have ever seen the whole Earth at a glance.

The primary purpose of this mission was to further progress toward the goal of landing men on the Moon by gaining operational experience and testing the Apollo system. The Apollo 8 mission was sped up when NASA management heard the Russian space program might be attempting to launch a crew to the moon. The Russian program had been leading the early era of space exploration and NASA crew were racing to catch up.

This mission itself was a daunting task. Every object involved in this voyage was moving and the spacecraft had to arrive exactly 79.9 miles (128.7 km) ahead of the Moon, itself moving at about 2,000 miles per hour. Just a slight error and the astronauts could miss the lunar orbit.

One of the mission’s sublime moments was the sight of the Earth rising above the lunar horizon. The now iconic photo of the blue and white ball has become one of the most famous images ever recorded and reminds many of Earth’s small spot in our vast universe.

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Nina Sen is a frequent contributor to Live Science’s Life’s Little Mysteries series: an exploration and explanation of our world’s phenomena, both natural and man-made. She also writes astronomy photo stories for Live Science's sister site Space.com.