Apollo 8
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Date: 23/12/2018

Apollo 8, by Wikipedia https://en.wikipedia.org/wiki?curid=663 / CC BY SA 3.0

Apollo 8

Apollo 8, the second manned spaceflight mission in the United States Apollo space program, was launched on December 21, 1968, and became the first manned spacecraft to leave low Earth orbit, reach the Earth's Moon, orbit it and return safely to Earth. The three-astronaut crew — Commander Frank Borman, Command Module Pilot James Lovell, and Lunar Module Pilot William Anders — became the first humans to travel beyond low Earth orbit; see Earth as a whole planet; enter the gravity well of another celestial body (Earth's moon); orbit another celestial body (Earth's moon); directly see the far side of the Moon with their own eyes; witness an Earthrise; escape the gravity of another celestial body (Earth's moon); and re-enter the gravitational well of Earth. The 1968 mission, the third flight of the Saturn V rocket and that rocket's first crewed launch, was also the first human spaceflight launch from the Kennedy Space Center, Florida, located adjacent to Cape Canaveral Air Force Station.

Originally planned as a second crewed Lunar Module/Command Module test, to be flown in a higher, elliptical medium Earth orbit in early 1969, the mission profile was changed in August 1968 to a more ambitious Command Module-only lunar orbital flight to be flown in December, because the Lunar Module was not yet ready to make its first flight. This led to the swapping of Borman's crew with Jim McDivitt's crew, who were planned to fly the first Lunar Module flight in low Earth orbit, which became the Apollo 9 mission. This left Borman's crew with two to three months less training and preparation time than originally planned, and replaced the need for Lunar Module training with translunar navigation training.

Apollo 8 took 68 hours (2.8 days) to travel the distance to the Moon. It orbited ten times over the course of 20 hours, during which the crew made a Christmas Eve television broadcast where they read the first 10 verses from the Book of Genesis. At the time, the broadcast was the most watched TV program ever. Apollo 8's successful mission paved the way for Apollo 11 to fulfill U.S. President John F. Kennedy's goal of landing a man on the Moon before the end of the 1960s. The Apollo 8 astronauts returned to Earth on December 27, 1968, when their spacecraft splashed down in the Northern Pacific Ocean. The crew members were named "Time" magazine's "Men of the Year" for 1968 upon their return.

The initial crew assignment of Frank Borman as Commander, Michael Collins as Command Module Pilot (CMP) and William Anders as Lunar Module Pilot (LMP) for the third crewed Apollo flight was officially announced on November 20, 1967. Collins was replaced by Jim Lovell in July 1968, after suffering a cervical disc herniation that required surgery to repair. This crew was unique among pre-shuttle era missions in that the commander was not the most experienced member of the crew, as Lovell had flown twice before, on Gemini VII and Gemini XII. This was also the first case of the rarity of an astronaut who had commanded a spaceflight mission subsequently flying as a non-commander, as Lovell had previously commanded Gemini XII.

The backup crew assignment of Neil Armstrong as Commander, Michael Collins as CMP and Buzz Aldrin as LMP for the third crewed Apollo flight was officially announced at the same time as the prime crew. When Lovell was reassigned to the prime crew, Aldrin was moved ...