Project Apollo
Encyclopedia
The Apollo program was the spaceflight
Human spaceflight
Human spaceflight is spaceflight with humans on the spacecraft. When a spacecraft is manned, it can be piloted directly, as opposed to machine or robotic space probes and remotely-controlled satellites....

 effort carried out by the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

' National Aeronautics and Space Administration
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 (NASA), that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President
President of the United States
The President of the United States of America is the head of state and head of government of the United States. The president leads the executive branch of the federal government and is the commander-in-chief of the United States Armed Forces....

 John F. Kennedy
John F. Kennedy
John Fitzgerald "Jack" Kennedy , often referred to by his initials JFK, was the 35th President of the United States, serving from 1961 until his assassination in 1963....

 proposed the national goal of "landing a man on the Moon and returning him safely to the Earth" by the end of the 1960s in a May 25, 1961 address to Congress.

Kennedy's goal was accomplished with the Apollo 11
Apollo 11
In early 1969, Bill Anders accepted a job with the National Space Council effective in August 1969 and announced his retirement as an astronaut. At that point Ken Mattingly was moved from the support crew into parallel training with Anders as backup Command Module Pilot in case Apollo 11 was...

 mission when astronauts Neil Armstrong
Neil Armstrong
Neil Alden Armstrong is an American former astronaut, test pilot, aerospace engineer, university professor, United States Naval Aviator, and the first person to set foot upon the Moon....

 and Buzz Aldrin
Buzz Aldrin
Buzz Aldrin is an American mechanical engineer, retired United States Air Force pilot and astronaut who was the Lunar Module pilot on Apollo 11, the first manned lunar landing in history...

 landed their Lunar Module
Apollo Lunar Module
The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

 (LM) on the Moon on July 20, 1969 and walked on its surface while Michael Collins
Michael Collins (astronaut)
Michael Collins is a former American astronaut and test pilot. Selected as part of the third group of fourteen astronauts in 1963, he flew in space twice. His first spaceflight was Gemini 10, in which he and command pilot John Young performed two rendezvous with different spacecraft and Collins...

 remained in lunar orbit
Lunar orbit
In astronomy, lunar orbit refers to the orbit of an object around the Moon.As used in the space program, this refers not to the orbit of the Moon about the Earth, but to orbits by various manned or unmanned spacecraft around the Moon...

 in the command spacecraft
Apollo Command/Service Module
The Command/Service Module was one of two spacecraft, along with the Lunar Module, used for the United States Apollo program which landed astronauts on the Moon. It was built for NASA by North American Aviation...

, and all three landed safely on Earth on July 24. Five subsequent Apollo missions also landed astronaut
Astronaut
An astronaut or cosmonaut is a person trained by a human spaceflight program to command, pilot, or serve as a crew member of a spacecraft....

s on the Moon, the last in December 1972. In these six spaceflights, 12 men walked on the Moon. These are the only times humans have landed on another celestial body
Celestial Body
Celestial Body is a Croatian film directed by Lukas Nola. It was released in 2000....

.

Apollo ran from 1961 to 1972, following the Mercury
Project Mercury
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

 and Gemini
Project Gemini
Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

 programs. It used Saturn family rockets
Saturn (rocket family)
The Saturn family of American rocket boosters was developed by a team of mostly German rocket scientists led by Wernher von Braun to launch heavy payloads to Earth orbit and beyond. Originally proposed as a military satellite launcher, they were adopted as the launch vehicles for the Apollo moon...

 as launch vehicles. Apollo / Saturn vehicles were also used for an Apollo Applications program
Apollo Applications program
The Apollo Applications Program was established by NASA headquarters in 1968 to develop science-based manned space missions using surplus material from the Apollo program...

 which consisted of three Skylab space station
Skylab
Skylab was a space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of...

 missions in 1973–74, and a joint U.S.–Soviet mission
Apollo-Soyuz Test Project
-Backup crew:-Crew notes:Jack Swigert had originally been assigned as the command module pilot for the ASTP prime crew, but prior to the official announcement he was removed as punishment for his involvement in the Apollo 15 postage stamp scandal.-Soyuz crew:...

 in 1975.

Apollo was successful despite two major setbacks: the 1967 Apollo 1
Apollo 1
Apollo 1 was scheduled to be the first manned mission of the Apollo manned lunar landing program, with a target launch date of February 21, 1967. A cabin fire during a launch pad test on January 27 at Launch Pad 34 at Cape Canaveral killed all three crew members: Command Pilot Virgil "Gus"...

 cabin fire that killed the entire crew during a pre-launch test; and an in-flight failure on the 1970 Apollo 13
Apollo 13
Apollo 13 was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The craft was launched on April 11, 1970, at 13:13 CST. The landing was aborted after an oxygen tank exploded two days later, crippling the service module upon which the Command...

 flight which disabled the command spacecraft's propulsion and life support, forcing the crew to use the LM as a "lifeboat" for these functions until they could return to Earth safely.

Apollo set major milestones in human spaceflight. It stands alone in sending manned missions beyond low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

; Apollo 8
Apollo 8
Apollo 8, the second manned mission in the American Apollo space program, was the first human spaceflight to leave Earth orbit; the first to be captured by and escape from the gravitational field of another celestial body; and the first crewed voyage to return to Earth from another celestial...

 was the first manned spacecraft to orbit another celestial body, while Apollo 17
Apollo 17
Apollo 17 was the eleventh and final manned mission in the American Apollo space program. Launched at 12:33 a.m. EST on December 7, 1972, with a three-member crew consisting of Commander Eugene Cernan, Command Module Pilot Ronald Evans, and Lunar Module Pilot Harrison Schmitt, Apollo 17 remains the...

 marked the last moonwalk and the last manned mission beyond low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

. The program spurred advances in many areas of technology incidental to rocketry and manned spaceflight, including avionics
Avionics
Avionics are electronic systems used on aircraft, artificial satellites and spacecraft.Avionic systems include communications, navigation, the display and management of multiple systems and the hundreds of systems that are fitted to aircraft to meet individual roles...

, telecommunications, and computers. Apollo also sparked interest in many fields of engineering
Engineering
Engineering is the discipline, art, skill and profession of acquiring and applying scientific, mathematical, economic, social, and practical knowledge, in order to design and build structures, machines, devices, systems, materials and processes that safely realize improvements to the lives of...

 and left many physical facilities and machines developed for the program as landmarks. Its command modules and other objects and artifacts are displayed throughout the world, notably in the Smithsonian's Air and Space Museums
National Air and Space Museum
The National Air and Space Museum of the Smithsonian Institution holds the largest collection of historic aircraft and spacecraft in the world. It was established in 1976. Located in Washington, D.C., United States, it is a center for research into the history and science of aviation and...

 in Washington, DC and at NASA's centers in Florida, Texas and Alabama. The Apollo 13 Command Module is housed at the Kansas Cosmosphere and Space Center
Kansas Cosmosphere and Space Center
The Kansas Cosmosphere and Space Center is a museum and educational facility in Hutchinson, Kansas that is best known for the display and restoration of spaceflight artifacts and educational camps...

 in Hutchinson, Kansas.

Background

The Apollo program was conceived early in 1960, during the Eisenhower
Dwight D. Eisenhower
Dwight David "Ike" Eisenhower was the 34th President of the United States, from 1953 until 1961. He was a five-star general in the United States Army...

 administration, as a follow-up to America's Mercury program. While the Mercury capsule could only support one astronaut on a limited earth orbital mission, the Apollo spacecraft was to be able to carry three astronauts on a circumlunar flight and eventually to a lunar landing. The program was named after the Greek god of light and music
Apollo
Apollo is one of the most important and complex of the Olympian deities in Greek and Roman mythology...

 by NASA manager Abe Silverstein
Abe Silverstein
Abraham "Abe" Silverstein was an American engineer who played an important part in the United States space program. He was a longtime manager at the National Aeronautics and Space Administration and its predecessor, the National Advisory Committee for Aeronautics...

, who later said that "I was naming the spacecraft like I'd name my baby." Dr. Silverstein recalls he chose the name after perusing a book of mythology at home one evening, early in 1960. He thought that the image of "Apollo riding his chariot across the Sun was appropriate to the grand scale of the proposed program." While NASA went ahead with planning for Apollo, funding for the program was far from certain given Eisenhower's ambivalent attitude to manned spaceflight.
In November 1960, John F. Kennedy was elected president after a campaign that promised American superiority over the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

 in the fields of space exploration and missile defense. Using space exploration as a symbol of national prestige, he warned of a "missile gap
Missile gap
The missile gap was the term used in the United States for the perceived disparity between the number and power of the weapons in the U.S.S.R. and U.S. ballistic missile arsenals during the Cold War. The gap only existed in exaggerated estimates made by the Gaither Committee in 1957 and United...

" between the two nations, pledging to make the U.S. not "first but, first and, first if, but first period." Despite Kennedy's rhetoric, he did not immediately come to a decision on the status of the Apollo program once he became president. He knew little about the technical details of the space program, and was put off by the massive financial commitment required by a manned Moon landing. When Kennedy's newly-appointed NASA Administrator James Webb requested a 30 percent budget increase for his agency, Kennedy supported an acceleration of NASA's large booster program but deferred a decision on the broader issue.

On April 12, 1961, Soviet cosmonaut Yuri Gagarin
Yuri Gagarin
Yuri Alekseyevich Gagarin was a Soviet pilot and cosmonaut. He was the first human to journey into outer space, when his Vostok spacecraft completed an orbit of the Earth on April 12, 1961....

 became the first person to fly in space, reinforcing American fears about being left behind in a technological competition with the Soviet Union. At a meeting of the U.S. House Committee on Science and Astronautics one day after Gagarin's flight, many congressmen pledged their support for a crash program aimed at ensuring that America would catch up. Kennedy, however, was circumspect in his response to the news, refusing to make a commitment on America's response to the Soviets.

On April 20, Kennedy sent a memo to Vice President Lyndon B. Johnson
Lyndon B. Johnson
Lyndon Baines Johnson , often referred to as LBJ, was the 36th President of the United States after his service as the 37th Vice President of the United States...

, asking Johnson to look into the status of America's space program, and into programs that could offer NASA the opportunity to catch up. Johnson responded approximately one week later, concluding that "we are neither making maximum effort nor achieving results necessary if this country is to reach a position of leadership." His memo concluded that a manned Moon landing was far enough in the future that it was likely the United States would achieve it first.

On May 25, 1961, Kennedy announced his support for the Apollo program during a special address to a joint session of Congress:
At the time of Kennedy's proposal, only one American had flown in space—less than a month earlier—and NASA had not yet sent an astronaut into orbit. Even some NASA employees doubted whether Kennedy's ambitious goal could be met. Kennedy even came close to agreeing to a joint US-USSR moon mission, to eliminate duplication of effort.

Landing men on the Moon by the end of 1969 required the most sudden burst of technological creativity, and the largest commitment of resources ($24 billion), ever made by any nation in peacetime. At its peak, the Apollo program employed 400,000 people and required the support of over 20,000 industrial firms and universities.

It also required the conversion of the Space Task Group
Space Task Group
The Space Task Group was a working group of NASA engineers created in 1958, tasked with superintending America's manned spaceflight programs. It was headed by Robert Gilruth andbased at the Langley Research Center in Hampton, Virginia. After President John F...

, which had been directing the nation's manned space program from NASA's Langley Research Center
Langley Research Center
Langley Research Center is the oldest of NASA's field centers, located in Hampton, Virginia, United States. It directly borders Poquoson, Virginia and Langley Air Force Base...

, into a new NASA center, the Manned Spacecraft Center (MSC), to be housed in a new facility built in Houston, Texas on land donated by Rice University
Rice University
William Marsh Rice University, commonly referred to as Rice University or Rice, is a private research university located on a heavily wooded campus in Houston, Texas, United States...

. In September 1962, by which time two Project Mercury
Project Mercury
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

 astronauts had orbited the Earth, and construction of the MSC facility was under way, Kennedy visited Rice to reiterate his challenge in a famous speech:

Choosing a mission mode

Once Kennedy had defined a goal, the Apollo mission planners were faced with the challenge of designing a set of flights that could meet it while minimizing risk to human life, cost, and demands on technology and astronaut skill. Four possible mission modes were considered:

  • Direct Ascent
    Direct ascent
    Direct ascent was a proposed method for a mission to the Moon. In the United States, direct ascent proposed using the enormous Nova rocket to launch a spacecraft directly to the Moon, where it would land tail-first and then launch off the Moon back to Earth...

    :
    A spacecraft would travel directly to the Moon as a unit, land, and return leaving its landing stage on the Moon. This plan would have required a more powerful launch vehicle, the planned Nova rocket.
  • Earth Orbit Rendezvous
    Earth orbit rendezvous
    Earth orbit rendezvous is a type of space rendezvous and a spaceflight methodology most notable for enabling round trip human missions to the moon...

     (EOR):
    Multiple rockets (up to 15 in some plans) would be launched, each carrying various parts of a Direct Ascent spacecraft and propulsion units that would have enabled the spacecraft to escape earth orbit. After a docking in earth orbit, the spacecraft would have landed on the Moon as a unit.
  • Lunar Surface Rendezvous: Two spacecraft would be launched in succession. The first, an automated vehicle carrying propellants, would land on the Moon and would be followed some time later by the manned vehicle. Propellant would be transferred from the automated vehicle to the manned vehicle before the manned vehicle could return to Earth.
  • Lunar Orbit Rendezvous
    Lunar orbit rendezvous
    Lunar orbit rendezvous is a key concept for human landing on the Moon and returning to Earth.In a LOR mission a main spacecraft and a smaller lunar module travel together into lunar orbit. The lunar module then independently descends to the lunar surface. After completion of the mission there, a...

     (LOR):
    One Saturn V
    Saturn V
    The Saturn V was an American human-rated expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. A multistage liquid-fueled launch vehicle, NASA launched 13 Saturn Vs from the Kennedy Space Center, Florida with no loss of crew or payload...

     would launch a spacecraft that was composed of modular parts. A command module
    Apollo Command/Service Module
    The Command/Service Module was one of two spacecraft, along with the Lunar Module, used for the United States Apollo program which landed astronauts on the Moon. It was built for NASA by North American Aviation...

     would remain in orbit around the Moon, while a lunar excursion module
    Apollo Lunar Module
    The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

     would descend to the Moon and then return to dock with the command ship while still in lunar orbit. In contrast with the other plans, LOR required only a small part of the spacecraft to land on the Moon, thereby minimizing the mass to be launched from the Moon's surface for the return trip.


In early 1961, direct ascent was generally the mission mode in favor at NASA. Many engineers feared that a rendezvous —let alone a docking— neither of which had been attempted even in Earth orbit, would be extremely difficult in lunar orbit
Lunar orbit
In astronomy, lunar orbit refers to the orbit of an object around the Moon.As used in the space program, this refers not to the orbit of the Moon about the Earth, but to orbits by various manned or unmanned spacecraft around the Moon...

. However, dissenters including John Houbolt
John Houbolt
John Cornelius Houbolt is a retired aerospace engineer. He is generally credited with having effectively promoted the lunar mission mode called Lunar Orbit Rendezvous or LOR. This flight path was first endorsed by Wernher von Braun in June 1961 and was chosen for Apollo program in early 1962...

 at Langley Research Center
Langley Research Center
Langley Research Center is the oldest of NASA's field centers, located in Hampton, Virginia, United States. It directly borders Poquoson, Virginia and Langley Air Force Base...

 emphasized the important weight reductions that were offered by the LOR approach. Throughout 1960 and 1961, Houbolt campaigned for the recognition of LOR as a viable and practical option. Bypassing the NASA hierarchy, he sent a series of memos and reports on the issue to Associate Administrator Robert Seamans
Robert Seamans
Robert Channing Seamans, Jr. was a NASA Deputy Administrator and MIT professor.-Birth and education:He was born in Salem, Massachusetts to Pauline and Robert Seamans. His great-great-grandfather was Otis Tufts...

; while acknowledging that he spoke "somewhat as a voice in the wilderness," Houbolt pleaded that LOR should not be discounted in studies of the question.

Seamans' establishment of the Golovin committee in July 1961 represented a turning point in NASA's mission mode decision. While the ad-hoc committee was intended to provide a recommendation on the boosters to be used in the Apollo program, it recognized that the mode decision was an important part of this question. The committee recommended in favor of a hybrid EOR-LOR mode, but its consideration of LOR —as well as Houbolt's ceaseless work— played an important role in publicizing the workability of the approach. In late 1961 and early 1962, members of NASA's Space Task Group
Space Task Group
The Space Task Group was a working group of NASA engineers created in 1958, tasked with superintending America's manned spaceflight programs. It was headed by Robert Gilruth andbased at the Langley Research Center in Hampton, Virginia. After President John F...

 at the Langley Center (which was in process of transitioning to the newly formed Manned Spacecraft Center in Houston), began to come around to support for LOR. The engineers at Marshall Space Flight Center
Marshall Space Flight Center
The George C. Marshall Space Flight Center is the U.S. government's civilian rocketry and spacecraft propulsion research center. The largest center of NASA, MSFC's first mission was developing the Saturn launch vehicles for the Apollo moon program...

 took longer to become convinced of its merits, but their conversion was announced by Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...

 at a briefing in June 1962. NASA's formal decision in favor of LOR was announced on July 11, 1962. Space historian James Hansen concludes that:
Without NASA's adoption of this stubbornly held minority opinion in 1962, the United States may still have reached the Moon, but almost certainly it would not have been accomplished by the end of the 1960s, President Kennedy's target date.


The LOR method had the advantage of allowing the lander spacecraft to be used as a "life boat" in the event of a failure of the command ship. This happened on Apollo 13
Apollo 13
Apollo 13 was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The craft was launched on April 11, 1970, at 13:13 CST. The landing was aborted after an oxygen tank exploded two days later, crippling the service module upon which the Command...

 when an oxygen tank failure left the command ship without electrical power. The Lunar Module provided propulsion, electrical power and life support to get the crew home safely.

Spacecraft

Preliminary design studies of Apollo spacecraft began in 1960 as a three-man command module supported by one of several service modules providing propulsion and electrical power, sized for use in various possible missions, such as: shuttle service to a space station
Space station
A space station is a spacecraft capable of supporting a crew which is designed to remain in space for an extended period of time, and to which other spacecraft can dock. A space station is distinguished from other spacecraft used for human spaceflight by its lack of major propulsion or landing...

, a circumlunar flight
Circumlunar trajectory
A Circumlunar trajectory, Trans-Lunar trajectory or Lunar free return is a type of free return trajectory which takes a spacecraft from Earth, around the far side of the Moon, and back to Earth.-Background:...

, or return to Earth from a lunar landing. Once the Moon landing goal became official, detailed design began of the Command/Service Module (CSM), in which the crew would spend the entire direct-ascent mission and lift off from the lunar surface for the return trip. (An even larger, separate propulsion module would have been required for the lunar descent.)

The final choice of lunar orbit rendezvous changed the CSM's role to a translunar ferry used to take the crew and a new spacecraft, the Lunar Module (LM), which would take two men to the lunar surface and return them to the CSM.

As the program concept evolved, use of the term "module" changed from its true meaning of an interchangeable component of systems with multiple variants, to simply a component of the complete lunar landing system.

Command/Service Module

The Command Module (CM) was the crew cabin, surrounded by a conical re-entry heat shield, designed to carry three astronauts from launch to lunar orbit and back to an Earth ocean splashdown. As such, it was the only component of the Apollo spacecraft to survive without major configuration changes as the program evolved from the early Apollo study designs. Equipment carried by the Command Module included reaction control engines
Reaction control system
A reaction control system is a subsystem of a spacecraft whose purpose is attitude control and steering by the use of thrusters. An RCS system is capable of providing small amounts of thrust in any desired direction or combination of directions. An RCS is also capable of providing torque to allow...

, a docking tunnel, guidance and navigation systems and the Apollo Guidance Computer
Apollo Guidance Computer
The Apollo Guidance Computer provided onboard computation and control for guidance, navigation, and control of the Command Module and Lunar Module spacecraft of the Apollo program...

.

Attached to the Command Module was the cylindrical Service Module (SM), which housed the service propulsion engine and its propellants, the fuel cell power system, four maneuvering thruster quads, a high-gain S-band antenna for communications between the Moon and Earth, and storage tanks for water and oxygen. On the last three lunar missions, it also carried a scientific instrument package. Because its configuration was chosen early before the selection of lunar orbit rendezvous, the service propulsion engine was sized to lift the CSM off of the Moon, and thus oversized to about twice the thrust required for translunar flight.

As used in the actual lunar program, the two modules remained attached throughout most of the flight to make a single ferry craft known as the Command/Service Module (CSM), which carried a separate lunar lander (only half as heavy as the CSM) to the Moon, and the astronauts home to Earth. Just before re-entry, the Service Module was discarded and only the Command Module re-entered the atmosphere, using its heat shield to survive the intense heat caused by air friction. After re-entry it deployed parachutes that slowed its descent, allowing a smooth splashdown in the ocean.

Under the leadership of Harrison Storms
Harrison Storms
Harrison Allen Storms Jr. , nicknamed Stormy, was an American aeronautical engineer best known for his role in managing the design and construction of the command module for the Apollo program.-Early life and career:...

, North American Aviation
North American Aviation
North American Aviation was a major US aerospace manufacturer, responsible for a number of historic aircraft, including the T-6 Texan trainer, the P-51 Mustang fighter, the B-25 Mitchell bomber, the F-86 Sabre jet fighter, the X-15 rocket plane, and the XB-70, as well as Apollo Command and Service...

 won the contract to build the CSM, and also the second stage of the Saturn V launch vehicle for NASA. Relations between North American and NASA were strained during the winter of 1965-66 by delivery delays, quality shortfalls, and cost overruns in both components. They were strained even more a year later when a cabin fire killed the crew of Apollo 1
Apollo 1
Apollo 1 was scheduled to be the first manned mission of the Apollo manned lunar landing program, with a target launch date of February 21, 1967. A cabin fire during a launch pad test on January 27 at Launch Pad 34 at Cape Canaveral killed all three crew members: Command Pilot Virgil "Gus"...

 during a ground test. The cause was determined to be an electrical short in the wiring of the Command Module; while the determination of responsibility for the accident was complex, the review board concluded that "deficiencies existed in Command Module design, workmanship and quality control." This eventually led to the removal of Storms as Command Module program manager.

Lunar Module

The Lunar Module (LM)
Apollo Lunar Module
The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

 (originally known as the Lunar Excursion Module, or LEM), was designed to fly between lunar orbit and the surface, landing two astronauts on the Moon and taking them back to the Command Module. It had no aerodynamic heat shield and was of a construction so lightweight that it would not have been able to fly through the Earth's atmosphere. It consisted of two stages, a descent and an ascent stage. The descent stage contained compartments which carried cargo such as the Apollo Lunar Surface Experiment Package and Lunar Rover
Lunar rover
The Lunar Roving Vehicle or lunar rover was a battery-powered four-wheeled rover used on the Moon in the last three missions of the American Apollo program during 1971 and 1972...

.

The contract for design and construction of the Lunar Module was awarded to Grumman Aircraft Engineering Corporation, and the project was overseen by Tom Kelly
Tom Kelly (engineer)
Thomas Joseph Kelly was an American aerospace engineer.Thomas J. Kelly graduated from Cornell University in 1951, where he was a member of the Quill and Dagger society...

. There were also problems with the Lunar Module; due to delays in the test program, the LM became a "pacing item," meaning that it was in danger of delaying the schedule of the whole Apollo program. The first manned LM was not ready for its planned Earth orbit test in December 1968, but the program was kept on schedule by cancelling a second manned Earth orbit LM flight.

Launch vehicles

When the team of engineers led by Wernher von Braun
Wernher von Braun
Wernher Magnus Maximilian, Freiherr von Braun was a German rocket scientist, aerospace engineer, space architect, and one of the leading figures in the development of rocket technology in Nazi Germany during World War II and in the United States after that.A former member of the Nazi party,...

 began planning for the Apollo program, it was not yet clear what mission their rockets would have to support. Direct ascent would require a more powerful launch vehicle, the planned Nova, which could carry a very large payload to the Moon. NASA's decision in favor of Lunar Orbit Rendezvous re-oriented the work of the Marshall Space Flight Center
Marshall Space Flight Center
The George C. Marshall Space Flight Center is the U.S. government's civilian rocketry and spacecraft propulsion research center. The largest center of NASA, MSFC's first mission was developing the Saturn launch vehicles for the Apollo moon program...

 towards the development of the Saturn I
Saturn I
The Saturn I was the United States' first heavy-lift dedicated space launcher, a rocket designed specifically to launch large payloads into low Earth orbit. Most of the rocket's power came from a clustered lower stage consisting of tanks taken from older rocket designs and strapped together to make...

, Saturn IB
Saturn IB
The Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration for use in the Apollo program...

 and Saturn V
Saturn V
The Saturn V was an American human-rated expendable rocket used by NASA's Apollo and Skylab programs from 1967 until 1973. A multistage liquid-fueled launch vehicle, NASA launched 13 Saturn Vs from the Kennedy Space Center, Florida with no loss of crew or payload...

. While the Saturn V was less powerful than the Nova would have been, it was still much more powerful than any rocket developed before, or since. (The USSR N1 was approximately as powerful, but it was never successful.)

Saturn IB


The Saturn IB
Saturn IB
The Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration for use in the Apollo program...

 was an upgraded version of the earlier Saturn I
Saturn I
The Saturn I was the United States' first heavy-lift dedicated space launcher, a rocket designed specifically to launch large payloads into low Earth orbit. Most of the rocket's power came from a clustered lower stage consisting of tanks taken from older rocket designs and strapped together to make...

 rocket, which was used in early Apollo boilerplate launches. It consisted of:
  • An S-IB
    S-IB
    The S-IB stage was the first stage of the Saturn IB launch vehicle, which was used for Earth orbital missions. It was composed of nine propellant containers, eight fins, a thrust structure assembly, eight H-1 rocket engines, and many other components...

     first stage powered by eight H-1
    H-1 (rocket engine)
    Rocketdyne's H-1 is a thrust liquid-propellant rocket engine burning LOX and RP-1. The H-1 was developed for use in the S-IB first stage of the Saturn I and Saturn IB rockets, where it was used in clusters of eight engines...

     engines burning RP-1
    RP-1
    RP-1 is a highly refined form of kerosene outwardly similar to jet fuel, used as a rocket fuel. Although having a lower specific impulse than liquid hydrogen , RP-1 is cheaper, can be stored at room temperature, is far less of an explosive hazard and is far denser...

     with LOX
    Lox
    Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...

     oxidizer, to produce 1600000 pound-forces (7,117.2 kN) of thrust;
  • An S-IVB-200
    S-IVB
    The S-IVB was built by the Douglas Aircraft Company and served as the third stage on the Saturn V and second stage on the Saturn IB. It had one J-2 engine...

     second stage, powered by one J-2
    J-2 (rocket engine)
    Rocketdyne's J-2 rocket engine was a major component of the Saturn V rocket used in the Apollo program to send men to the Moon. Five J-2 engines were used on the S-II second stage, and one J-2 was used on the S-IVB third stage. The S-IVB was also used as the second stage of the smaller Saturn IB...

     engine burning liquid hydrogen
    Liquid hydrogen
    Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form.To exist as a liquid, H2 must be pressurized above and cooled below hydrogen's Critical point. However, for hydrogen to be in a full liquid state without boiling off, it needs to be...

     with LOX
    Lox
    Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...

     oxidizer, to produce 225000 lbf (1,000.8 kN) of thrust; and
  • An Instrument Unit
    Saturn V Instrument Unit
    The Saturn V Instrument Unit is a ring-shaped structure fitted to the top of the Saturn V rocket's third stage and the Saturn IB's second stage . It was immediately below the SLA panels that contained the Lunar Module. The Instrument Unit contains the guidance system for the Saturn V rocket...

     which contained the rocket's guidance system.


The Saturn IB was capable of putting a partially-fueled Command/Service Module, or a Lunar Module, into earth orbit. It was used in five of the Apollo test missions including the first manned mission. It was also used in the manned missions for the Skylab program and the Apollo-Soyuz Test Project.

Saturn V


The Saturn V was a three-stage rocket consisting of:
  • An S-IC
    S-IC
    The S-IC was the first stage of the Saturn V rocket. The S-IC first stage was built by The Boeing Company. Like the first stages of most rockets, most of its mass of over two thousand metric tonnes at launch was propellant, in this case RP-1 rocket fuel and liquid oxygen oxidizer...

     first stage, powered by five F-1
    F-1 (rocket engine)
    The F-1 is a rocket engine developed by Rocketdyne and used in the Saturn V. Five F-1 engines were used in the S-IC first stage of each Saturn V, which served as the main launch vehicle in the Apollo program. The F-1 is still the most powerful single-chamber liquid-fueled rocket engine ever...

     engines arranged in a cross pattern, burning RP-1
    RP-1
    RP-1 is a highly refined form of kerosene outwardly similar to jet fuel, used as a rocket fuel. Although having a lower specific impulse than liquid hydrogen , RP-1 is cheaper, can be stored at room temperature, is far less of an explosive hazard and is far denser...

     with LOX
    Lox
    Lox is salmon fillet that has been cured. In its most popular form, it is thinly sliced—less than in thickness—and, typically, served on a bagel, often with cream cheese, onion, tomato, cucumber and capers...

     oxidizer to produce 7500000 lbf (33,361.7 kN) of thrust. They burned for 2.5 minutes, accelerating the spacecraft to a speed of approximately 6,000 miles per hour (2.68 km/s).
  • An S-II
    S-II
    The S-II was the second stage of the Saturn V rocket. It was built by North American Aviation. Using liquid hydrogen and liquid oxygen it had five J-2 engines in a cross pattern...

     second stage, powered by five of the J-2 engines used in the S-IVB. They burned for approximately six minutes, taking the spacecraft to a speed of 15,300 miles per hour (6.84 km/s) and an altitude of about 115 miles (185 km).
  • An S-IVB-500
    S-IVB
    The S-IVB was built by the Douglas Aircraft Company and served as the third stage on the Saturn V and second stage on the Saturn IB. It had one J-2 engine...

     third stage similar to the Saturn IB's second stage, with capability to restart the J-2 engine. The engine would burn for approximately two and a half minutes and shut down when a low-Earth parking orbit was achieved. After approximately two orbits to confirm the spacecraft was ready to commit to the lunar trip, the engine was restarted to make the translunar injection
    Trans Lunar Injection
    A Trans Lunar Injection is a propulsive maneuver used to set a spacecraft on a trajectory which will arrive at the Moon.Typical lunar transfer trajectories approximate Hohmann transfers, although low energy transfers have also been used in some cases, as with the Hiten probe...

     maneuver taking the spacecraft into an extremely high orbit where it would be captured by the Moon's gravity.
  • An instrument unit with a guidance system similar to that used on the Saturn IB.


Three Saturn V vehicles launched on Earth orbital flights. Two of the three (Apollo 4
Apollo 4
Apollo 4, , was the first unmanned test flight of the Saturn V launch vehicle, which was ultimately used by the Apollo program to send the first men to the Moon...

 and 6
Apollo 6
Apollo 6, launched on April 4, 1968, was the Apollo program's second and last A type mission—unmanned test flight of its Saturn V launch vehicle. It was intended to demonstrate full lunar injection capability of the Saturn V, and the capability of the Command Module's heat shield to withstand a...

) were unmanned tests of the command and service modules
Apollo Command/Service Module
The Command/Service Module was one of two spacecraft, along with the Lunar Module, used for the United States Apollo program which landed astronauts on the Moon. It was built for NASA by North American Aviation...

, and the third was a manned flight, Apollo 9
Apollo 9
Apollo 9, the third manned mission in the American Apollo space program, was the first flight of the Command/Service Module with the Lunar Module...

, testing the lunar module
Apollo Lunar Module
The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

. Nine Saturn Vs launched manned Apollo missions to the Moon, including Apollo 11
Apollo 11
In early 1969, Bill Anders accepted a job with the National Space Council effective in August 1969 and announced his retirement as an astronaut. At that point Ken Mattingly was moved from the support crew into parallel training with Anders as backup Command Module Pilot in case Apollo 11 was...

. It was also used for the unmanned launch of Skylab.

Missions

Unmanned missions

Apollo required more than six years of spacecraft and launch vehicle development and testing before the first manned missions could be flown. Test flights of the Saturn I
Saturn I
The Saturn I was the United States' first heavy-lift dedicated space launcher, a rocket designed specifically to launch large payloads into low Earth orbit. Most of the rocket's power came from a clustered lower stage consisting of tanks taken from older rocket designs and strapped together to make...

 launch vehicle began in October 1961 and lasted until September 1964. Three further Saturn I launches carried boilerplate models of the Apollo command/service module. Two pad abort test
Pad abort test
A pad abort test is a test of a launch escape system to determine how well the system could get the crew of a spacecraft to safety in an emergency on the launch pad.- Project Mercury :Section sources....

s of the launch escape system
Launch escape system
A Launch Escape System is a top-mounted rocket connected to the crew module of a crewed spacecraft and used to quickly separate the crew module from the rest of the rocket in case of emergency. Since the escape rockets are above the crew module, an LES typically uses separate nozzles which are...

 took place in 1963 and 1965 at the White Sands Missile Range
White Sands Missile Range
White Sands Missile Range is a rocket range of almost in parts of five counties in southern New Mexico. The largest military installation in the United States, WSMR includes the and the WSMR Otera Mesa bombing range...

. Three unmanned tests of Apollo components with the Saturn IB
Saturn IB
The Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration for use in the Apollo program...

 (Apollo-Saturn, or AS) were officially designated (in their chronological order of launch) as AS-201
AS-201
AS-201 , flown February 26, 1966, was the first unmanned test flight of an entire production Block I Apollo Command/Service Module and the Saturn IB launch vehicle. The spacecraft consisted of the second Block I command module and the first Block I service module...

, AS-203
AS-203
AS-203 was an unmanned flight of the Saturn IB rocket on July 5, 1966. It carried no Apollo Command/Service Module spacecraft, as its purpose was to verify the design of the S-IVB rocket stage restart capability that would later be used in the Apollo program to boost astronauts from Earth orbit to...

, and AS-202
AS-202
AS-202 was the second unmanned, suborbital test flight of a production Block I Apollo Command/Service Module launched with the Saturn IB launch vehicle. It launched August 25, 1966 and was the first flight which included the spacecraft Guidance and Navigation Control system and fuel cells...

.

The only unmanned missions to be publicly designated as "Apollo" followed by a sequence number were Apollo 4, Apollo 5 and Apollo 6. The simple numbering was started at "4" to follow the three Apollo-Saturn IB flights, though all subsequent flights kept the "AS" designations: AS-204 and following for Saturn IB flights, and AS-501 and following for Saturn V flights.

Apollo 4
Apollo 4
Apollo 4, , was the first unmanned test flight of the Saturn V launch vehicle, which was ultimately used by the Apollo program to send the first men to the Moon...

 was the first unmanned test flight of the Saturn V launch vehicle, carrying a Command/Service Module (CSM). Launched on November 9, 1967, Apollo 4 exemplified George Mueller
George Mueller (NASA)
George Mueller was Associate Administrator of the NASA Office of Manned Space Flight from September 1963 until December 1969...

's strategy of "all up" testing. Rather than being tested stage by stage, as most rockets were, the Saturn V would be flown for the first time as one unit. Walter Cronkite
Walter Cronkite
Walter Leland Cronkite, Jr. was an American broadcast journalist, best known as anchorman for the CBS Evening News for 19 years . During the heyday of CBS News in the 1960s and 1970s, he was often cited as "the most trusted man in America" after being so named in an opinion poll...

 covered the launch from a broadcast booth about 4 miles (6 km) from the launch site. The extreme noise and vibrations from the launch nearly shook the broadcast booth apart- ceiling tiles fell and windows shook. At one point, Cronkite was forced to dampen the booth's plate glass window to prevent it from shattering. This launch showed that additional protective measures were necessary to protect structures in the immediate vicinity. Future launches used a damping mechanism directly at the launchpad which proved effective in limiting the generated noise. The mission was a highly successful one, demonstrating the capability of the Command Module's heat shield to survive a trans-lunar return reentry by using the Service Module engine to ram it into the atmosphere at higher than the usual earth-orbital reentry speed.

Apollo 5
Apollo 5
Apollo 5 was the first unmanned flight of the Apollo Lunar Module, which would later carry astronauts to the lunar surface. It lifted off on January 22, 1968 with a Saturn IB rocket.-Objectives:...

 was the first unmanned test flight of the Lunar Module (LM) in Earth orbit, launched on January 22, 1968, by a Saturn IB. The critical LM engines were successfully tested (though a computer programming error cut one test firing short), including an in-flight test of the second stage engine in "abort mode," in which the ascent engine is fired simultaneously with the jettison of the descent stage. This capability was made available, only to be used in the event of a critical problem on the Moon landing, such as running out of descent fuel, but was never needed.

Apollo 6
Apollo 6
Apollo 6, launched on April 4, 1968, was the Apollo program's second and last A type mission—unmanned test flight of its Saturn V launch vehicle. It was intended to demonstrate full lunar injection capability of the Saturn V, and the capability of the Command Module's heat shield to withstand a...

 was the last unmanned Saturn V flight, launched on April 4, 1968. It carried a CSM and a Lunar Module Test Article near the mass of the Lunar Module for ballast. It was planned to achieve translunar injection, then after 5 minutes, use the Service Module engine to return the CM to Earth, thus demonstrating the Saturn V's ability to send the Apollo craft to the Moon, and a direct return-to-Earth abort capability. However, "pogo" vibrations
Pogo oscillation
Pogo oscillation is a potentially dangerous type of self-excited combustion oscillation in liquid fuel rocket engines. This oscillation results in variations of thrust from the engines, causing variations of acceleration on the rocket's structure, giving variations in fuel pressure and flow rate....

 caused premature shutdown of two second-stage engines, and failure of the third stage to re-light for the translunar injection. Instead, the Service Module engine was used as in Apollo 4 to raise the craft to a higher Earth orbit, and bring the CM back at a velocity midway between that of low Earth orbit and lunar return velocity. This mission was considered successful enough to launch men on the next Saturn V flight, since fixes for the vibration problem were identified.

Manned missions

The manned missions carried three astronauts, designated as Commander (CDR), Command Module Pilot (CMP), and Lunar Module Pilot (LMP). Besides exercising all crew command decisions, the Commander was the primary pilot of both spacecraft (when present) and was first to exit the LM on the surface of the Moon. The CMP functioned as navigator, usually performed the initial docking with the LM, and remained in the Command/Service Module when his companions flew the LM. The LMP functioned as engineering officer, monitoring the systems of both spacecraft. On a landing mission, he accompanied the Commander on the lunar surface. On the last flight, the LMP was a professional geologist, Dr. Harrison Schmitt
Harrison Schmitt
Harrison Hagan "Jack" Schmitt is an American geologist, a retired NASA astronaut, university professor, and a former U.S. senator from New Mexico....

.

Apollo 7
Apollo 7
Apollo 7 was the first manned mission in the American Apollo space program, and the first manned US space flight after a cabin fire killed the crew of what was to have been the first manned mission, AS-204 , during a launch pad test in 1967...

, launched on October 11, 1968, was the first manned mission in the program. It was an 11-day Earth-orbital flight intended to test the Command Module, redesigned following the Apollo 1 fire. It was the first manned launch of the Saturn IB launch vehicle and the first three-man American space mission.
Between December 21, 1968 and May 18, 1969, NASA planned to launch three manned test / practice missions using the Saturn V launch vehicle and the complete spacecraft including the LM. But by the summer of 1968 it became clear to program managers that a fully functional LM would not be available for the Apollo 8 launch. Rather than waste the Saturn V on another simple Earth-orbiting mission, they chose to send the crew planned to make the second orbital LM test in Apollo 9, to orbit the Moon in the CSM on Apollo 8
Apollo 8
Apollo 8, the second manned mission in the American Apollo space program, was the first human spaceflight to leave Earth orbit; the first to be captured by and escape from the gravitational field of another celestial body; and the first crewed voyage to return to Earth from another celestial...

 during Christmas. The original idea for this switch was the brainchild of George Low
George Low
George Michael Low, born George Wilhelm Low was a NASA administrator and 14th President of Rensselaer Polytechnic Institute. He was born near Vienna, Austria to Artur and Gertrude Burger Low, small business people in Austria...

, Manager of the Apollo Spacecraft Program Office. Although it has often been claimed that this change was made as a direct response to Soviet attempts to fly a piloted Zond
Zond program
Zond was the name given to two distinct series of Soviet unmanned space program undertaken from 1964 to 1970. The first series based on 3MV planetary probe was intended to gather information about nearby planets...

 spacecraft around the Moon, there is no evidence that this was the case. NASA officials were aware of the Soviet Zond flights, but the timing of the Zond missions does not correspond well with the extensive written record from NASA about the Apollo 8 decision. The Apollo 8 decision was primarily based upon the LM schedule, not fear of the Soviets beating the Americans to the Moon.

This was followed by the first orbital manned LM flight on Apollo 9
Apollo 9
Apollo 9, the third manned mission in the American Apollo space program, was the first flight of the Command/Service Module with the Lunar Module...

 (with the original Apollo 8 crew), and the lunar "dress rehearsal" Apollo 10
Apollo 10
Apollo 10 was the fourth manned mission in the American Apollo space program. It was an F type mission—its purpose was to be a "dry run" for the Apollo 11 mission, testing all of the procedures and components of a Moon landing without actually landing on the Moon itself. The mission included the...

 which took the LM to within 50000 feet (15.2 km) of the surface, but did not land.
The next two flights (11 and 12) included successful Moon landings. The Apollo 13
Apollo 13
Apollo 13 was the seventh manned mission in the American Apollo space program and the third intended to land on the Moon. The craft was launched on April 11, 1970, at 13:13 CST. The landing was aborted after an oxygen tank exploded two days later, crippling the service module upon which the Command...

 mission was aborted before the landing attempt, but the crew returned safely to Earth. The four subsequent Apollo missions (14 through 17) included successful Moon landings. The last three of these were J-class missions that included the use of Lunar Rover
Lunar rover
The Lunar Roving Vehicle or lunar rover was a battery-powered four-wheeled rover used on the Moon in the last three missions of the American Apollo program during 1971 and 1972...

s.

Apollo 17
Apollo 17
Apollo 17 was the eleventh and final manned mission in the American Apollo space program. Launched at 12:33 a.m. EST on December 7, 1972, with a three-member crew consisting of Commander Eugene Cernan, Command Module Pilot Ronald Evans, and Lunar Module Pilot Harrison Schmitt, Apollo 17 remains the...

, launched December 7, 1972, was the last Apollo mission to the Moon. Mission commander Eugene Cernan was the last person to leave the Moon's surface. The crew returned safely to Earth on December 19, 1972.

Astronauts

Forty-one astronauts were assigned to fly Apollo spacecraft; thirty-two of them were part of the Apollo program, with the rest not flying until the subsequent Skylab and Apollo-Soyuz programs. Twenty-four of the Apollo program astronauts left Earth’s orbit and flew around the Moon (Apollo 7 and Apollo 9 did not leave low Earth orbit).

Twelve of these astronauts walked on the Moon’s surface, and six of those drove a lunar rover on the Moon. While three astronauts flew to the Moon twice, none of them landed on the Moon more than once. The nine Apollo missions to the moon occurred between December of 1968 and December of 1972.

Apart from these twenty-four people who visited the Moon, no human being has gone beyond low Earth orbit. They have, therefore, been farther from the Earth than anyone else. They are also the only people to have directly viewed the far side of the Moon. The twelve who walked on the Moon are the only people ever to have set foot on an astronomical object other than the Earth.
Of the twenty-four lunar astronauts taking part in the Moon missions, two went on to command a Skylab mission, one commanded Apollo-Soyuz, one flew as commander for shuttle approach and landing tests and two went on to command orbital shuttle missions. A total of twenty-four Apollo-era astronauts (as well as pre-Apollo astronaut John Glenn) flew the space shuttle.

Capsule Communicator

Mission rules specified that, in most circumstances, only one person in the Mission Control Center
Mission Control Center
A mission control center is an entity that manages aerospace vehicle flights, usually from the point of lift-off until the landing or the end of the mission. A staff of flight controllers and other support personnel monitor all aspects of the mission using telemetry, and send commands to the...

 would communicate directly with the in-flight crew; this was to be another astronaut, who would be best able to understand the situation in the spacecraft and communicate with the crew in the clearest way. These individuals were designated Capsule Communicators or CAPCOMs, a term carried over from the Mercury
Project Mercury
In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

 and Gemini
Project Gemini
Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

 programs. They were usually chosen from the backup and support crews, and worked in shifts during long missions. The periodic beeps heard during communications with the astronauts are known as Quindar tones
Quindar tones
Quindar Tones, most often referred to as the "beeps" that were heard during the American Apollo space missions, were a means by which remote transmitters on Earth were turned on and off so that the Capsule communicator could communicate with the crews of the spacecraft...

.

Samples returned

The Apollo program returned 841.5 lb (381.7 kg) of rocks and other material from the Moon, much of which is stored at the Lunar Receiving Laboratory
Lunar Receiving Laboratory
The Lunar Receiving Laboratory was a facility at NASA's Lyndon B. Johnson Space Center that was constructed to quarantine astronauts and material brought back from the Moon during the Apollo program to mitigate the risk of back-contamination...

 in Houston. The only sources of Moon rocks on Earth are those collected from the Apollo program, the former Soviet Union's Luna missions
Luna programme
The Luna programme , occasionally called Lunik or Lunnik, was a series of robotic spacecraft missions sent to the Moon by the Soviet Union between 1959 and 1976. Fifteen were successful, each designed as either an orbiter or lander, and accomplished many firsts in space exploration...

, and lunar meteorites.

The rocks collected from the Moon are extremely old compared to rocks found on Earth, as measured by radiometric dating
Radiometric dating
Radiometric dating is a technique used to date materials such as rocks, usually based on a comparison between the observed abundance of a naturally occurring radioactive isotope and its decay products, using known decay rates...

 techniques. They range in age from about 3.2 billion years old for the basalt
Basalt
Basalt is a common extrusive volcanic rock. It is usually grey to black and fine-grained due to rapid cooling of lava at the surface of a planet. It may be porphyritic containing larger crystals in a fine matrix, or vesicular, or frothy scoria. Unweathered basalt is black or grey...

ic samples derived from the lunar mare
Lunar mare
The lunar maria are large, dark, basaltic plains on Earth's Moon, formed by ancient volcanic eruptions. They were dubbed maria, Latin for "seas", by early astronomers who mistook them for actual seas. They are less reflective than the "highlands" as a result of their iron-rich compositions, and...

, to about 4.6 billion years for samples derived from the highlands crust. As such, they represent samples from a very early period in the development of the Solar System
Solar System
The Solar System consists of the Sun and the astronomical objects gravitationally bound in orbit around it, all of which formed from the collapse of a giant molecular cloud approximately 4.6 billion years ago. The vast majority of the system's mass is in the Sun...

 that is largely missing from Earth. One important rock found during the Apollo Program was the Genesis Rock
Genesis Rock
The Genesis Rock is a sample of Moon retrieved by Apollo 15 astronauts James Irwin and David Scott in 1971 during their second lunar EVA.Chemical analysis of the Genesis Rock indicated it is an anorthosite, composed mostly of the plagioclase feldspar, anorthite. The rock was formed in the early...

, retrieved by astronauts James Irwin
James Irwin
James Benson Irwin was an American astronaut and engineer. He served as Lunar Module pilot for Apollo 15, the fourth human lunar landing; he was the eighth person to walk on the Moon.-Early life:...

 and David Scott
David Scott
David Randolph Scott is an American engineer, test pilot, retired U.S. Air Force officer, and former NASA astronaut and engineer, who was one of the third group of astronauts selected by NASA in October 1963...

 during the Apollo 15 mission. This rock, called anorthosite
Anorthosite
Anorthosite is a phaneritic, intrusive igneous rock characterized by a predominance of plagioclase feldspar , and a minimal mafic component...

, is composed almost exclusively of the calcium-rich feldspar mineral anorthite
Anorthite
Anorthite is the calcium endmember of plagioclase feldspar. Plagioclase is an abundant mineral in the Earth's crust. The formula of pure anorthite is CaAl2Si2O8.-Mineralogy :...

, and is believed to be representative of the highland crust. A geochemical component called KREEP
KREEP
KREEP, an acronym built from the letters K , REE and P , is a geochemical component of some lunar impact melt breccia and basalt rocks...

 was discovered that has no known terrestrial counterpart. Together, KREEP and the anorthositic samples have been used to infer that the outer portion of the Moon was once completely molten (see lunar magma ocean
Lunar magma ocean
According to the giant impact hypothesis a large amount of energy was liberated in the formation of the Moon and it is predicted that as a result a large portion of the Moon was once completely molten, forming a lunar magma ocean...

).

Almost all the rocks show evidence for having been affected by impact processes. For instance, many samples appear to be pitted with micrometeoroid
Micrometeoroid
A micrometeoroid is a tiny meteoroid; a small particle of rock in space, usually weighing less than a gram. A micrometeor or micrometeorite is such a particle that enters the Earth's atmosphere or falls to Earth.-Scientific interest:...

 impact craters, something which is never seen on earth due to its thick atmosphere. Additionally, many show signs of being subjected to high pressure shock waves that are generated during impact events. Some of the returned samples are of impact melt, referring to materials that are melted near an impact crater. Finally, all samples returned from the Moon are highly breccia
Breccia
Breccia is a rock composed of broken fragments of minerals or rock cemented together by a fine-grained matrix, that can be either similar to or different from the composition of the fragments....

ted as a result of being subjected to multiple impact events.

Analysis of composition of the lunar samples support the giant impact hypothesis
Giant impact hypothesis
The giant impact hypothesis states that the Moon was created out of the debris left over from a collision between the young Earth and a Mars-sized body. The colliding body is sometimes called Theia for the mythical Greek Titan who was the mother of Selene, the goddess of the moon.The giant impact...

, that the Moon was created through a "giant impact" of a large astronomical body with the Earth.

Program costs and cancellation

When President Kennedy first chartered the Moon landing program, a preliminary cost estimate of $7 billion was generated, but this proved an extremely unrealistic guess of what could not possibly be determined precisely, and James Webb used his administrator's judgement to change the estimate to $20 billion before giving it to Vice President Johnson.

Webb's estimate shocked many at the time (including the President), but ultimately proved to be reasonably accurate. In January 1969, NASA prepared an itemized estimate of the combined cost of the Mercury, Gemini and Apollo programs. The total for Apollo came to $23.9 billion, itemized as follows:
  • Apollo spacecraft: $7,945.0 million
  • Saturn I launch vehicles: $767.1 million
  • Saturn IB launch vehicles: $1,131.2 million
  • Saturn V launch vehicles: $6,871.1 million
  • Launch vehicle engine development: $854.2 million
  • Mission support: $1,432.3 million
  • Tracking and data acquisition: $664.1 million
  • Ground facilities: $1,830.3 million
  • Operation of installations: $2,420.6 million


The final cost of project Apollo was reported to Congress as $25.4 billion in 1973. It took up the majority of NASA's budget while it was being developed. For example, in 1966 it accounted for about 60 percent of NASA's total $5.2 billion budget.

In 2009, NASA held a symposium on project costs which presented an estimate of the Apollo program costs in 2005 dollars as roughly $170 billion. This included all research and development
Research and development
The phrase research and development , according to the Organization for Economic Co-operation and Development, refers to "creative work undertaken on a systematic basis in order to increase the stock of knowledge, including knowledge of man, culture and society, and the use of this stock of...

 costs; the procurement of 15 Saturn V rockets, 16 Command/Service Modules, 12 Lunar Modules, plus program support and management costs; construction expenses for facilities and their upgrading, and costs for flight operations. This was based on a Congressional Budget Office
Congressional Budget Office
The Congressional Budget Office is a federal agency within the legislative branch of the United States government that provides economic data to Congress....

 report, A Budgetary Analysis of NASA’s New Vision for Space, September 2004.

Canceled missions

Originally three additional lunar landing missions had been planned, as Apollo 18 through Apollo 20. In light of the drastically shrinking NASA
NASA
The National Aeronautics and Space Administration is the agency of the United States government that is responsible for the nation's civilian space program and for aeronautics and aerospace research...

 budget and the decision not to produce a second batch of Saturn Vs, these missions were canceled to make funds available for the development of the Space Shuttle
Space Shuttle
The Space Shuttle was a manned orbital rocket and spacecraft system operated by NASA on 135 missions from 1981 to 2011. The system combined rocket launch, orbital spacecraft, and re-entry spaceplane with modular add-ons...

, and to make their Apollo spacecraft and Saturn V launch vehicles available to the Skylab program. Only one of the remaining Saturn Vs was actually used to launch the Skylab orbital laboratory in 1973; the others became museum exhibits at the John F. Kennedy Space Center on Merritt Island, Florida
Florida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...

, George C. Marshall Space Center
Marshall Space Flight Center
The George C. Marshall Space Flight Center is the U.S. government's civilian rocketry and spacecraft propulsion research center. The largest center of NASA, MSFC's first mission was developing the Saturn launch vehicles for the Apollo moon program...

 in Huntsville
Huntsville, Alabama
Huntsville is a city located primarily in Madison County in the central part of the far northern region of the U.S. state of Alabama. Huntsville is the county seat of Madison County. The city extends west into neighboring Limestone County. Huntsville's population was 180,105 as of the 2010 Census....

, Alabama
Alabama
Alabama is a state located in the southeastern region of the United States. It is bordered by Tennessee to the north, Georgia to the east, Florida and the Gulf of Mexico to the south, and Mississippi to the west. Alabama ranks 30th in total land area and ranks second in the size of its inland...

, Michoud Assembly Facility
Michoud Assembly Facility
The Michoud Assembly Facility is an 832-acre site owned by NASA and located in New Orleans East, a large district within the city of New Orleans, Louisiana, United States. Organizationally, it is part of NASA's Marshall Space Flight Center...

 in New Orleans, Louisiana
Louisiana
Louisiana is a state located in the southern region of the United States of America. Its capital is Baton Rouge and largest city is New Orleans. Louisiana is the only state in the U.S. with political subdivisions termed parishes, which are local governments equivalent to counties...

, and Lyndon B. Johnson Space Center
Lyndon B. Johnson Space Center
The Lyndon B. Johnson Space Center is the National Aeronautics and Space Administration's center for human spaceflight training, research and flight control. The center consists of a complex of 100 buildings constructed on 1,620 acres in Houston, Texas, USA...

 in Houston, Texas
Texas
Texas is the second largest U.S. state by both area and population, and the largest state by area in the contiguous United States.The name, based on the Caddo word "Tejas" meaning "friends" or "allies", was applied by the Spanish to the Caddo themselves and to the region of their settlement in...

.

Apollo Applications Program

Following the success of the Apollo program, both NASA and its major contractors investigated several post-lunar applications for Apollo hardware. The Apollo Extension Series, later called the Apollo Applications Program
Apollo Applications program
The Apollo Applications Program was established by NASA headquarters in 1968 to develop science-based manned space missions using surplus material from the Apollo program...

, proposed up to 30 flights to Earth orbit. Many of these would use the space that the lunar module took up in the Saturn rocket to carry scientific equipment. Of all the plans, only two were implemented: the Skylab
Skylab
Skylab was a space station launched and operated by NASA, the space agency of the United States. Skylab orbited the Earth from 1973 to 1979, and included a workshop, a solar observatory, and other systems. It was launched unmanned by a modified Saturn V rocket, with a mass of...

 space station and the Apollo–Soyuz Test Project.

Skylab's fuselage was constructed from the second stage
S-IVB
The S-IVB was built by the Douglas Aircraft Company and served as the third stage on the Saturn V and second stage on the Saturn IB. It had one J-2 engine...

 of a Saturn IB, and the station was equipped with the Apollo Telescope Mount
Apollo Telescope Mount
The Apollo Telescope Mount, or ATM, is the name of a solar observatory that was attached to Skylab, the first US space station.The ATM was one of a number of projects that came out of the late 1960s Apollo Applications Program, which studied a wide variety of ways to use the infrastructure...

, itself based on a lunar module. The station's three crews were ferried into orbit atop Saturn IBs, riding in CSMs; the station itself had been launched with a modified Saturn V. Skylab's last crew departed the station on February 8, 1974, and the station itself re-entered the atmosphere in 1979, by which time it had become the oldest operational Apollo-Saturn component.

The Apollo-Soyuz Test Project involved a docking in Earth orbit between a CSM and a Soviet Soyuz spacecraft from July 15 to July 24, 1975. NASA's next manned mission would not be until STS-1
STS-1
STS-1 was the first orbital flight of NASA's Space Shuttle program. Space Shuttle Columbia launched on 12 April 1981, and returned to Earth on 14 April, having orbited the Earth 37 times during the 54.5-hour mission. It was the first American manned space flight since the Apollo-Soyuz Test Project...

 in 1981.

Recent observations

In 2008, Japan Aerospace Exploration Agency
Japan Aerospace Exploration Agency
The , or JAXA, is Japan's national aerospace agency. Through the merger of three previously independent organizations, JAXA was formed on October 1, 2003, as an Independent Administrative Institution administered by the Ministry of Education, Culture, Sports, Science and Technology and the...

's SELENE
SELENE
SELENE , better known in Japan by its nickname after the legendary Japanese moon princess, was the second Japanese lunar orbiter spacecraft. Produced by the Institute of Space and Astronautical Science and the National Space Development Agency , both now part of the Japan Aerospace Exploration...

 probe observed evidence of the halo surrounding the Apollo 15 lunar module blast crater while orbiting above the lunar surface. In 2009, NASA's robotic
Robotic spacecraft
A robotic spacecraft is a spacecraft with no humans on board, that is usually under telerobotic control. A robotic spacecraft designed to make scientific research measurements is often called a space probe. Many space missions are more suited to telerobotic rather than crewed operation, due to...

 Lunar Reconnaissance Orbiter
Lunar Reconnaissance Orbiter
The Lunar Precursor Robotic Program is a program of robotic spacecraft missions which NASA will use to prepare for future human spaceflight missions to the Moon. Two LPRP missions, the Lunar Reconnaissance Orbiter and the Lunar Crater Observation and Sensing Satellite , were launched in June 2009...

, while orbiting 50 kilometres (31.1 mi) above the moon, photographed the remnants of the Apollo program left on the lunar surface, and photographed each site where manned Apollo flights landed.

In a November 16, 2009 editorial, The New York Times opined:

Proposed future lunar landing missions, such as the Google Lunar X Prize
Google Lunar X Prize
The Google Lunar X PRIZE, abbreviated GLXP, sometimes referred to as Moon 2.0, is a space competition organized by the X Prize Foundation, and sponsored by Google. It was announced at the Wired Nextfest on 13 September 2007...

, intend to record close-up images of the Apollo Lunar Module
Apollo Lunar Module
The Apollo Lunar Module was the lander portion of the Apollo spacecraft built for the US Apollo program by Grumman to carry a crew of two from lunar orbit to the surface and back...

s and other artificial objects on the surface.

Science and engineering

The Apollo program, specifically the lunar landings, has been called the greatest technological achievement in human history. The program stimulated many areas of technology. The flight computer
Apollo Guidance Computer
The Apollo Guidance Computer provided onboard computation and control for guidance, navigation, and control of the Command Module and Lunar Module spacecraft of the Apollo program...

 design used in both the lunar and command modules was, along with the Minuteman Missile System
LGM-30 Minuteman
The LGM-30 Minuteman is a U.S. nuclear missile, a land-based intercontinental ballistic missile . As of 2010, the version LGM-30G Minuteman-III is the only land-based ICBM in service in the United States...

, the driving force behind early research into integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...

s. The fuel cell
Fuel cell
A fuel cell is a device that converts the chemical energy from a fuel into electricity through a chemical reaction with oxygen or another oxidizing agent. Hydrogen is the most common fuel, but hydrocarbons such as natural gas and alcohols like methanol are sometimes used...

 developed for this program was the first practical fuel cell. Computer-controlled machining (CNC
Numerical control
Numerical control refers to the automation of machine tools that are operated by abstractly programmed commands encoded on a storage medium, as opposed to controlled manually via handwheels or levers, or mechanically automated via cams alone...

) was pioneered in fabricating Apollo structural components.

Cultural impact

The crew of Apollo 8, the first manned spacecraft to orbit the Moon, sent televised pictures of the Earth and the Moon back to Earth (left), and read from the creation story in the Biblical book of Genesis, on Christmas Eve
Christmas Eve
Christmas Eve refers to the evening or entire day preceding Christmas Day, a widely celebrated festival commemorating the birth of Jesus of Nazareth that takes place on December 25...

, 1968, This was believed to be the most widely watched television broadcast until that time. The mission and Christmas provided an inspiring end to 1968, which had been a bad year for the U.S., marked by Vietnam War
Vietnam War
The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

 protests, race riots, and the assassinations of civil rights leader Martin Luther King and Senator Robert Kennedy.

An estimated one-fifth of the population of the world watched the live transmission of the first Apollo
Apollo 11
In early 1969, Bill Anders accepted a job with the National Space Council effective in August 1969 and announced his retirement as an astronaut. At that point Ken Mattingly was moved from the support crew into parallel training with Anders as backup Command Module Pilot in case Apollo 11 was...

 moonwalk.

One legacy of the Apollo program is the now-common view of Earth as a fragile, small planet, captured in photographs taken by the astronauts during the lunar missions. The most famous, taken by the Apollo 17
Apollo 17
Apollo 17 was the eleventh and final manned mission in the American Apollo space program. Launched at 12:33 a.m. EST on December 7, 1972, with a three-member crew consisting of Commander Eugene Cernan, Command Module Pilot Ronald Evans, and Lunar Module Pilot Harrison Schmitt, Apollo 17 remains the...

 astronauts, is The Blue Marble
The Blue Marble
The Blue Marble is a famous photograph of the Earth taken on December 7, 1972, by the crew of the Apollo 17 spacecraft at a distance of about ....

 (right). These photographs have also motivated some people toward environmentalism
Environmentalism
Environmentalism is a broad philosophy, ideology and social movement regarding concerns for environmental conservation and improvement of the health of the environment, particularly as the measure for this health seeks to incorporate the concerns of non-human elements...

.

Many astronauts and cosmonauts have commented on the profound effects that seeing Earth from space has had on them; the 24 astronauts who traveled to the Moon are the only humans to have observed Earth from beyond low Earth orbit
Low Earth orbit
A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...

, and have traveled farther from Earth than anyone else to date.

The program succeeded in accomplishing one of President Kennedy's goals, which was to take on the Soviet Union in the space race and beat it by accomplishing a singular and significant achievement and thereby showcase the superiority of the capitalistic, free-market system as represented by the US. The Economist
The Economist
The Economist is an English-language weekly news and international affairs publication owned by The Economist Newspaper Ltd. and edited in offices in the City of Westminster, London, England. Continuous publication began under founder James Wilson in September 1843...

 noted, however, the irony that in order to achieve the goal the Apollo program was successful by organizing tremendous public resources within a vast, centralized bureaucracy under government direction.

Apollo 11 broadcast data restoration project

As part of Apollo 11's 40th anniversary in 2009, NASA spearheaded an effort to digitally restore the existing videotapes of the mission's live televised moonwalk. After an exhaustive three-year search for missing tapes of the original video of the Apollo 11 moonwalk, NASA concluded the data tapes had more than likely been accidentally erased.
The Moon landing data was recorded by a special Apollo TV camera
Apollo TV camera
Television cameras used on the Apollo Project's missions varied in design, with image quality improving significantly with each design. A camera was carried in the Apollo Command Module...

 which recorded in a format incompatible with broadcast TV. This resulted in lunar footage that had to be converted for the live television broadcast and stored on magnetic telemetry tapes. During the following years, a magnetic tape shortage prompted NASA to remove massive numbers of magnetic tapes from the National Archives and Records Administration
National Archives and Records Administration
The National Archives and Records Administration is an independent agency of the United States government charged with preserving and documenting government and historical records and with increasing public access to those documents, which comprise the National Archives...

 to be recorded over with newer satellite data. Stan Lebar, who designed and built the lunar camera at Westinghouse Electric Corporation, also worked with Nafzger to try to locate the missing tapes.
With a budget of $230,000, the surviving original lunar broadcast data from Apollo 11 was compiled by Nafzger and assigned to Lowry Digital for restoration. The video was processed to remove random noise and camera shake without destroying historical legitimacy. The images were from tapes in Australia, the CBS News archive, and kinescope
Kinescope
Kinescope , shortened to kine , also known as telerecording in Britain, is a recording of a television program made by filming the picture from a video monitor...

 recordings made at Johnson Space Center. The restored video, remaining in black and white, contains conservative digital enhancements and did not include sound quality improvements.

Documentaries

Numerous documentary film
Documentary film
Documentary films constitute a broad category of nonfictional motion pictures intended to document some aspect of reality, primarily for the purposes of instruction or maintaining a historical record...

s cover the Apollo program and the space race, including:
  • Moonwalk One
    Moonwalk One
    Moonwalk One is a feature-length documentary film about the flight of Apollo 11, which landed the first humans on the moon. Besides portraying the massive technological achievement of that event, the film places it in some historical context, and tries to capture the mood and feel of the people on...

     (1970)
  • For All Mankind
    For All Mankind
    For All Mankind is a 1989 documentary film documenting the Apollo missions of NASA. It was directed by Al Reinert.Music for the film was originally composed in 1983 by Brian Eno and released as an album entitled Apollo: Atmospheres and Soundtracks...

     (1989)
  • Moon Shot
    Moon Shot
    Moon Shot: The Inside Story of America's Race to the Moon is a book written by Mercury Seven astronaut Alan Shepard, with NBC News correspondent Jay Barbree and Associated Press space writer Howard Benedict. Astronaut Donald K. "Deke" Slayton is also listed as an author, although he died before...

     (documentary commemorating 25 years since the landings) (1994)
  • From the Earth to the Moon (TV miniseries) (1998)
  • Moon from the BBC miniseries The Planets (1999)
  • Magnificent Desolation: Walking on the Moon 3D
    Magnificent Desolation: Walking on the Moon 3D
    Magnificent Desolation: Walking on the Moon 3D is a 2005 IMAX 3D documentary film about the first humans on the Moon, the twelve astronauts in the Apollo program.-Production:...

     (2005)
  • In the Shadow of the Moon
    In the Shadow of the Moon
    In the Shadow of the Moon is a 2006 British documentary film about the United States' manned missions to the Moon. It premiered at the 2007 Sundance Film Festival, where it won the World Cinema Audience Award. In March 2008, it was the first film to win the Sir Arthur Clarke Award for Best Film...

     (2007)
  • When We Left Earth: The NASA Missions
    When We Left Earth: The NASA Missions
    When We Left Earth: The NASA Missions or NASA's Greatest Missions: When We Left Earth in the UK is a Discovery Channel HD documentary miniseries consisting of six episodes documenting American human spaceflight, spanning from the first Mercury flights through the Gemini program to the Apollo moon...

     (miniseries) (2008)
  • James May on the Moon
    James May on the Moon
    James May on the Moon is a British documentary in which James May commemorates the 40th anniversary of the Apollo moon landings. It was first aired on BBC Two on 21 June 2009 and on 10 November 2009 on BBC America in the United States....

     (documentary commemorating 40 years since the landings) (2009)
  • NASA's Story
    NASA's Story
    NASA's Story is a documentary series by Dangerous Films for the BBC to commemorate 50 years since the formation of NASA. The series looks at NASA's early history, the triumphs and disasters, notably the Apollo 1 fire, through to the manned Moon missions and the Space Shuttle era...


See also

  • Apollo 1
    Apollo 1
    Apollo 1 was scheduled to be the first manned mission of the Apollo manned lunar landing program, with a target launch date of February 21, 1967. A cabin fire during a launch pad test on January 27 at Launch Pad 34 at Cape Canaveral killed all three crew members: Command Pilot Virgil "Gus"...

     - unflown mission
  • Apollo 11 flight to the Moon
  • Apollo 18
    Apollo 18
    Apollo 18 may refer to:* One of the canceled Apollo missions of the American Apollo lunar program* The officially unnumbered Apollo spacecraft used in the Apollo–Soyuz Test Project* Apollo 18 , a 1992 album by They Might Be Giants...

    , Apollo 19, Apollo 20 - canceled missions
  • Apollo TV camera
    Apollo TV camera
    Television cameras used on the Apollo Project's missions varied in design, with image quality improving significantly with each design. A camera was carried in the Apollo Command Module...

  • AS-201
    AS-201
    AS-201 , flown February 26, 1966, was the first unmanned test flight of an entire production Block I Apollo Command/Service Module and the Saturn IB launch vehicle. The spacecraft consisted of the second Block I command module and the first Block I service module...

    , AS-202
    AS-202
    AS-202 was the second unmanned, suborbital test flight of a production Block I Apollo Command/Service Module launched with the Saturn IB launch vehicle. It launched August 25, 1966 and was the first flight which included the spacecraft Guidance and Navigation Control system and fuel cells...

    , AS-203
    AS-203
    AS-203 was an unmanned flight of the Saturn IB rocket on July 5, 1966. It carried no Apollo Command/Service Module spacecraft, as its purpose was to verify the design of the S-IVB rocket stage restart capability that would later be used in the Apollo program to boost astronauts from Earth orbit to...

    , Apollo 4
    Apollo 4
    Apollo 4, , was the first unmanned test flight of the Saturn V launch vehicle, which was ultimately used by the Apollo program to send the first men to the Moon...

    , Apollo 5
    Apollo 5
    Apollo 5 was the first unmanned flight of the Apollo Lunar Module, which would later carry astronauts to the lunar surface. It lifted off on January 22, 1968 with a Saturn IB rocket.-Objectives:...

    , Apollo 6
    Apollo 6
    Apollo 6, launched on April 4, 1968, was the Apollo program's second and last A type mission—unmanned test flight of its Saturn V launch vehicle. It was intended to demonstrate full lunar injection capability of the Saturn V, and the capability of the Command Module's heat shield to withstand a...

     - unmanned missions
  • List of man-made objects on the Moon
  • List of megaprojects
  • Lockheed Propulsion Company
    Lockheed Propulsion Company
    The Lockheed Propulsion Company was a division of the Lockheed Aircraft Corporation located in the Mentone, California area northeast of Redlands, California, adjacent to the Santa Ana River, from 1961 to 1975...

  • Pad Abort Tests
    Pad Abort Test-1 (Apollo)
    Pad Abort Test 1 was the first abort test of the Apollo spacecraft on November 7, 1963.-Objectives:Pad Abort Test 1 was a mission to investigate the effects on the Apollo spacecraft during an abort from the pad. The launch escape system had to be capable of pulling the spacecraft away from a...

  • Soviet manned lunar programs
  • Splashdown (spacecraft landing)
    Splashdown (spacecraft landing)
    Splashdown is the method of landing a spacecraft by parachute in a body of water. It was used by American manned spacecraft prior to the Space Shuttle program. It is also possible for the Russian Soyuz spacecraft and Chinese Shenzhou spacecraft to land in water, though this is only a contingency...


Further reading

  • Chaikin, Andrew
    Andrew Chaikin
    Andrew Chaikin is an American author, speaker and space journalist. He currently lives in Vermont.He is the author of A Man on the Moon, a detailed description of the Apollo missions to the moon...

    . A Man on the Moon. ISBN 0-14-027201-1. Chaikin interviewed all the surviving astronauts and others who worked with the program.
  • Collins, Michael
    Michael Collins (astronaut)
    Michael Collins is a former American astronaut and test pilot. Selected as part of the third group of fourteen astronauts in 1963, he flew in space twice. His first spaceflight was Gemini 10, in which he and command pilot John Young performed two rendezvous with different spacecraft and Collins...

    . Carrying the Fire; an Astronaut's journeys. Astronaut Mike Collins autobiography of his experiences as an astronaut, including his flight aboard Apollo 11
  • Cooper, Henry S. F. Jr. Thirteen: The Flight That Failed. ISBN 0-8018-5097-5. Although this book focuses on Apollo 13, it provides a wealth of background information on Apollo technology and procedures.
  • French, Francis
    Francis French
    Francis French is a book and magazine author from Manchester, England, specializing in space flight history. He is a former director of events for Sally Ride Science, and a director at the San Diego Air & Space Museum....

     and Burgess, Colin
    Colin Burgess (author)
    Colin Burgess is an Australian author and historian, specializing in space flight and military history. He is a former customer service manager for Qantas Airways, and a regular contributor to the collectSPACE online community. He lives in New South Wales...

    , In the Shadow of the Moon
    In the Shadow of the Moon (book)
    In the Shadow of the Moon: A Challenging Journey to Tranquility is a 2007 non-fiction book by space historians Francis French and Colin Burgess...

    : A Challenging Journey to Tranquility, 1965-1969. ISBN 978-0-8032-1128-5. History of the Apollo program from Apollo 1-11, including many interviews with the Apollo astronauts.
  • Kranz, Gene
    Gene Kranz
    Kranz's book, titled Failure Is Not an Option, published five years after the movie, stated, "...a creed that we all lived by: "Failure is not an option."" . The book has three index references for the phrase, but none of those give any indication of the phrase being apocryphal...

    , Failure is Not an Option. Factual, from the standpoint of a flight controller during the Mercury
    Project Mercury
    In January 1960 NASA awarded Western Electric Company a contract for the Mercury tracking network. The value of the contract was over $33 million. Also in January, McDonnell delivered the first production-type Mercury spacecraft, less than a year after award of the formal contract. On February 12,...

    , Gemini
    Project Gemini
    Project Gemini was the second human spaceflight program of NASA, the civilian space agency of the United States government. Project Gemini was conducted between projects Mercury and Apollo, with ten manned flights occurring in 1965 and 1966....

    , and Apollo space programs. ISBN 0-7432-0079-9.
  • Lovell, Jim
    Jim Lovell
    James "Jim" Arthur Lovell, Jr., is a former NASA astronaut and a retired captain in the United States Navy, most famous as the commander of the Apollo 13 mission, which suffered a critical failure en route to the Moon but was brought back safely to Earth by the efforts of the crew and mission...

    ; Kluger, Jeffrey. Lost Moon: The perilous voyage of Apollo 13 aka Apollo 13: Lost Moon. ISBN 0-618-05665-3. Details the flight of Apollo 13.
  • Orloff, Richard W. SP-4029 Apollo by the Numbers: A Statistical Reference
  • Pellegrino, Charles R.; Stoff, Joshua. Chariots for Apollo: The Untold Story Behind the Race to the Moon. ISBN 0-380-80261-9. Tells Grumman's story of building the Lunar Modules.
  • Scott, David
    David Scott
    David Randolph Scott is an American engineer, test pilot, retired U.S. Air Force officer, and former NASA astronaut and engineer, who was one of the third group of astronauts selected by NASA in October 1963...

    , and Alexei Leonov. Two Sides of the Moon: The Story of the Cold War Space Race. New York: St. Martin's, 2006. (ISBN 0312308663)
  • Robert C. Seamans, Jr. Project Apollo: The Tough Decisions. ISBN 0-1607-4954-9. History of the manned space program from September 1, 1960 to January 5, 1968.
  • Slayton, Donald K.
    Deke Slayton
    Donald Kent Slayton , better known as Deke Slayton, was an American World War II pilot and later, one of the original NASA Mercury Seven astronauts....

    ; Cassutt, Michael. Deke! An Autobiography. ISBN 0-312-85918-X. Account of Deke Slayton's life as an astronaut and of his work as chief of the astronaut office, including selection of Apollo crews. From origin to November 7, 1962 November 8, 1962 - September 30, 1964 October 1, 1964 - January 20, 1966 January 21, 1966 - July 13, 1974
  • Wilhelms, Don E. To a Rocky Moon. ISBN 0-8165-1065-2. The history of lunar exploration from a geologist's point of view.


External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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