Apollo 8, the second manned spaceflight mission
flown 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 Moon, orbit it, and return. The three-astronaut crew—Frank Borman, James
Lovell, and William Anders—were the first humans to witness and photograph an Earthrise
and to escape the gravity of a celestial body. Apollo 8 was the third flight
and the first crewed launch of the Saturn V rocket and was the first human
spaceflight from the Kennedy Space Center ,
located adjacent to Cape Canaveral Air Force Station in Florida
Originally planned as the second crewed Apollo Lunar Module and command module test, to be flown in an 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, as the lunar module was not yet ready to make its first flight. Astronaut Jim McDivitt's crew, who were training to fly the first lunar module flight in low Earth orbit, became the crew for the Apollo 9 mission, and Borman's crew were moved to the Apollo 8 mission. This left Borman's crew with two to three months' less training and preparation time than originally planned, and replaced the planned lunar module training with translunar navigation training.
Apollo 8 took 68 hours (almost three days) to travel the distance to the Moon. The crew orbited the Moon ten times over the course of twenty hours, during which they made a Christmas Eve television broadcast in which they read the first ten 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 fulfillU.S. Pacific Ocean .
The crew members were named Time magazine's "Men of the Year"
for 1968 upon their return.
In the late 1950s and early 1960s, theUnited States was
engaged in the Cold War, a geopolitical rivalry with the Soviet
Union . On October 4, 1957, the Soviet Union
launched Sputnik 1, the first artificial satellite. This unexpected success
stoked fears and imaginations around the world. It not only demonstrated that
the Soviet Union had the capability to deliver
nuclear weapons over intercontinental distances, it challenged American claims
of military, economic, and technological superiority. The launch precipitated
the Sputnik crisis and triggered the Space Race.
President John F. Kennedy believed that not only was it in the national interest of theUnited States Soviet Union to be more advanced in the field of space
exploration. He was determined that the United States
The Soviet Union had better booster rockets, which meant that Kennedy needed to choose a goal that was beyond the capacity of the existing generation of rocketry, one where the US and Soviet Union would be starting from a position of equality – something spectacular, even if it could not be justified on military, economic, or scientific grounds. After consulting with his experts and advisors, he chose such a project: to land a man on the Moon and return him to the Earth. This project already had a name: Project Apollo.
An early and crucial decision was the adoption of lunar orbit rendezvous, under which a specialized spacecraft would land on the lunar surface. The Apollo spacecraft therefore had three primary components: a command module (CM) with a cabin for the three astronauts, and the only part that would return to Earth; a service module (SM) to provide the command module with propulsion, electrical power, oxygen, and water; and a two-stage lunar module (LM), which comprised a descent stage for landing on the Moon and an ascent stage to return the astronauts to lunar orbit. This configuration could be launched by the Saturn V rocket that was then under development.
Originally planned as the second crewed Apollo Lunar Module and command module test, to be flown in an 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, as the lunar module was not yet ready to make its first flight. Astronaut Jim McDivitt's crew, who were training to fly the first lunar module flight in low Earth orbit, became the crew for the Apollo 9 mission, and Borman's crew were moved to the Apollo 8 mission. This left Borman's crew with two to three months' less training and preparation time than originally planned, and replaced the planned lunar module training with translunar navigation training.
Apollo 8 took 68 hours (almost three days) to travel the distance to the Moon. The crew orbited the Moon ten times over the course of twenty hours, during which they made a Christmas Eve television broadcast in which they read the first ten 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
Background
In the late 1950s and early 1960s, the
President John F. Kennedy believed that not only was it in the national interest of the
The Soviet Union had better booster rockets, which meant that Kennedy needed to choose a goal that was beyond the capacity of the existing generation of rocketry, one where the US and Soviet Union would be starting from a position of equality – something spectacular, even if it could not be justified on military, economic, or scientific grounds. After consulting with his experts and advisors, he chose such a project: to land a man on the Moon and return him to the Earth. This project already had a name: Project Apollo.
An early and crucial decision was the adoption of lunar orbit rendezvous, under which a specialized spacecraft would land on the lunar surface. The Apollo spacecraft therefore had three primary components: a command module (CM) with a cabin for the three astronauts, and the only part that would return to Earth; a service module (SM) to provide the command module with propulsion, electrical power, oxygen, and water; and a two-stage lunar module (LM), which comprised a descent stage for landing on the Moon and an ascent stage to return the astronauts to lunar orbit. This configuration could be launched by the Saturn V rocket that was then under development.
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