Which Apollo mission first carried astronauts into lunar orbit?

Which Apollo mission first carried astronauts into lunar orbit? Apollo 8 was the first Apollo mission to carry astronauts into lunar orbit. Its crew—Frank Borman, James Lovell, and William Anders—reached the Moon in December 1968, orbited it ten times, and returned safely to Earth.

Apollo 8 was originally planned as an Earth-orbit test of the command and lunar modules. Because the lunar module was not ready for that schedule, NASA changed the mission to a command-module-only lunar flight. The decision was bold: the crew had to perform a precise engine burn behind the Moon, where mission control could not communicate with them.

The mission entered lunar orbit on December 24, 1968, and spent about twenty hours circling the Moon. The astronauts became the first humans to see the Moon’s far side and photographed the famous Earthrise. Their flight demonstrated navigation, communications, heat-shield performance, and the lunar-orbit operations needed for a landing.

Apollo 7 had been the first crewed Apollo mission, but it stayed in Earth orbit. Apollo 9 later tested the complete lunar module in Earth orbit, and Apollo 10 rehearsed a landing before Apollo 11 landed in July 1969.