Apollo Program
Duration	1961–1972
Goal	"landing a man on the Moon and returning him safely to the Earth"
Tasks	Manned landing on the Moon, Scientific studies relating to the Lunar geology
Losses	Apollo 1, cabin fire, loss of crew during launch rehearsal Apollo 6 (partial failure), engine cutoffs during ascent kept mission from accomplishing assigned goals Apollo 13 (partial failure), crippled spacecraft unable to land on the Moon as planned
Organization	NASA
Spacecraft	Apollo CSM Lunar Module
Launcher	Saturn IB Saturn V
Legacy	First manned landing on another celestial body
Apollo 11 astronaut Buzz Aldrin, second person to walk on the Moon, July 21, 1969

The Apollo program was the spaceflight effort carried out by the United States' National Aeronautics and Space Administration (NASA), that landed the first humans on Earth's Moon. Conceived during the Presidency of Dwight D. Eisenhower, Apollo began in earnest after President John F. Kennedy 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.^[1][2]

Kennedy's goal was accomplished with the Apollo 11 mission when astronauts Neil Armstrong and Buzz Aldrin landed their Lunar Module (LM) on the Moon on July 20, 1969 and walked on its surface while Michael Collins remained in lunar orbit in the command spacecraft, and all three landed safely on Earth on July 24. Five subsequent Apollo missions also landed astronauts on the Moon, the last in December 1972. In these six spaceflights, 12 men walked on the Moon.^[3]

Apollo ran from 1961 to 1972, following the Mercury and Gemini programs. It used Saturn family rockets as launch vehicles. Apollo / Saturn vehicles were also used for an Apollo Applications program which consisted of three Skylab space station missions in 1973–74, and a joint U.S.–Soviet mission in 1975.

Apollo was successful despite two major setbacks: the 1967 Apollo 1 cabin fire that killed the entire crew during a pre-launch test; and an in-flight failure on the 1970 Apollo 13 flight which disabled the command spacecraft's propulsion and life support, forcing the crew to use the Lunar Module 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; Apollo 8 was the first manned spacecraft to orbit another celestial body, while Apollo 17 marked the last moonwalk and the last manned mission beyond low Earth orbit. The program spurred advances in many areas of technology incidental to rocketry and manned spaceflight, including avionics, telecommunications, and computers. Apollo also sparked interest in many fields of engineering 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 in Washington, DC, Kennedy Space Center Visitor Complex in Florida, Space Center Houston in Texas, and the U.S. Space and Rocket Center in Alabama. The Apollo 13 Command Module is housed at the Kansas Cosmosphere and Space Center in Hutchinson, Kansas.

Background[link]

The Apollo program was conceived early in 1960, during the Eisenhower 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, music, and the sun by NASA manager Abe Silverstein, who later said that "I was naming the spacecraft like I'd name my baby."^[4] 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."^[5] While NASA went ahead with planning for Apollo, funding for the program was far from certain given Eisenhower's ambivalent attitude to manned spaceflight.^[6]

President Kennedy addresses Congress, 1961, proposing to put a man on the Moon before the end of the decade

In November 1960, John F. Kennedy was elected president after a campaign that promised American superiority over the Soviet Union in the fields of space exploration and missile defense. Using space exploration as a symbol of national prestige, he warned of a "missile gap" between the two nations, pledging to make the U.S. not "first but, first and, first if, but first period."^[7] 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.^[8] 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.^[9]

On April 12, 1961, Soviet cosmonaut Yuri Gagarin 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.^[10] Kennedy, however, was circumspect in his response to the news, refusing to make a commitment on America's response to the Soviets.^[11]

On April 20, Kennedy sent a memo to Vice President Lyndon B. Johnson, asking Johnson to look into the status of America's space program, and into programs that could offer NASA the opportunity to catch up.^[12] 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."^[13] 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.^[13]

On May 25, 1961, Kennedy announced his support for the Apollo program during a special address to a joint session of Congress:

I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the Moon and returning him safely to the Earth. No single space project in this period will be more impressive to mankind, or more important in the long-range exploration of space; and none will be so difficult or expensive to accomplish.^[1]

President Kennedy speaks at Rice University (17 min, 47 sec)

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.^[2] Kennedy even came close to agreeing to a joint US-USSR moon mission, to eliminate duplication of effort.^[14]

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.^[15]

President Kennedy delivers a speech at Rice University on the American space program, September 12, 1962.

It also required the conversion of the Space Task Group, which had been directing the nation's manned space program from NASA's Langley Research Center, 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. In September 1962, by which time two Project Mercury 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:

"But why, some say, the moon? Why choose this as our goal? And they may well ask, why climb the highest mountain? Why, 35 years ago, fly the Atlantic? ...

We choose to go to the Moon. We choose to go to the Moon in this decade and do the other things, not because they are easy, but because they are hard; because that goal will serve to organize and measure the best of our energies and skills; because that challenge is one that we are willing to accept, one we are unwilling to postpone, and one we intend to win ...

Many years ago the great British explorer George Mallory, who was to die on Mount Everest, was asked why did he want to climb it. He said, 'Because it is there.' Well, space is there, and we're going to climb it, and the Moon and the planets are there, and new hopes for knowledge and peace are there. And, therefore, as we set sail we ask God's blessing on the most hazardous and dangerous and greatest adventure on which man has ever embarked."

—^[16]

Choosing a mission mode[link]

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:

Early Apollo configuration for Direct Ascent and Earth Orbit Rendezvous, 1961

• Direct Ascent: 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 (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 (LOR): One Saturn V would launch a spacecraft that was composed of modular parts. A command module would remain in orbit around the Moon, while a lunar excursion module 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.

An early model of the pre-LOR concept, c. 1962

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. However, dissenters including John Houbolt at Langley Research Center 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; 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.^[17]

Seamans' establishment of the Golovin committee in July 1961 represented a turning point in NASA's mission mode decision.^[18] 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 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.^[19] The engineers at Marshall Space Flight Center took longer to become convinced of its merits, but their conversion was announced by Wernher von Braun 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.^[20]

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 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[link]

Apollo CSM-LM, compared to scale with the smaller Gemini and Mercury spacecraft. Their Saturn, Titan and Atlas launch vehicles are also compared, in a smaller scale.

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, a circumlunar flight, 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[link]

Apollo 15 CSM in lunar orbit

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, a docking tunnel, guidance and navigation systems and the Apollo Guidance Computer.

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, North American Aviation 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.^[21] They were strained even more a year later when a cabin fire killed the crew of Apollo 1 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."^[22] This eventually led to the removal of Storms as Command Module program manager.^[23]

Lunar Module[link]

Apollo 16 LM on the Moon

The Lunar Module (LM) (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.

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. 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.^[24] The first manned LM was not ready for its planned Earth orbit test in December 1968, but the program was kept on schedule by canceling a second manned Earth orbit LM flight.

Launch vehicles[link]

When the team of engineers led by Wernher von Braun began planning for the Apollo program, it was not yet clear how much payload capacity was required for a manned lunar landing. Sending the three-man Apollo Command Module directly to the lunar surface and back would require an extremely large launch vehicle, the Nova, which could send over 130,000 pounds (59,000 kg) to the Moon. NASA's decision to use the Lunar Orbit Rendezvous method eliminated the need for Nova and met the capability of the Saturn rocket family, so the Marshall Space Flight Center proceeded to develop the Saturn I, Saturn IB and Saturn V. While the Saturn V was less powerful than the Nova would have been, it still holds the record for largest payload capacity (260,000 lb/120,000 kg to LEO or (100,000 lb/45,000 kg to the Moon) of any rocket developed as of 2012. The closest comparable launch systems were the Energia (220,000 lb/100,000 kg to LEO) and the unsuccessful N1 (200,000 lb/91,000 kg to LEO), which the Soviet Union developed for manned lunar flight in competition with Apollo.

A Saturn IB rocket launches Apollo 7, October 11, 1968.

Saturn IB[link]

The Saturn IB was an upgraded version of the earlier Saturn I rocket.^[25] It consisted of:

• An S-IB first stage powered by eight H-1 engines burning RP-1 with liquid oxygen (LOX) oxidizer, to produce 1,600,000 pounds-force (7,100 kN) of thrust;
• An S-IVB-200 second stage, powered by one J-2 engine burning liquid hydrogen fuel with LOX, to produce 225,000 lbf (1,000 kN) of thrust; and
• An Instrument Unit 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.^[26] 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[link]

A Saturn V rocket launches Apollo 11 in 1969

The Saturn V was a three-stage rocket consisting of:

• An S-IC first stage, powered by five F-1 engines arranged in a cross pattern, burning RP-1 with LOX oxidizer to produce 7,500,000 lbf (33,000 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).^[27]
• An S-II 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).^[28]
• An S-IVB-500 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 maneuver taking the spacecraft into an extremely high orbit where it would be captured by the Moon's gravity.^[29]
• 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 and 6) were unmanned tests of the command and service modules, and the third was a manned flight, Apollo 9, testing the lunar module. Nine Saturn Vs launched manned Apollo missions to the Moon, including Apollo 11. It was also used for the unmanned launch of Skylab.

Missions[link]

Far side of the Moon by Apollo 16

Unmanned missions[link]

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 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 (CSM). Two pad abort tests of the launch escape system took place in 1963 and 1965 at the White Sands Missile Range.

Three unmanned tests of Apollo components with the Saturn IB (Apollo-Saturn, or AS) were officially designated (in their chronological order of launch) as AS-201, AS-203, and AS-202. According to original plan the first CSM manned orbital mission AS-204, called Apollo 1, should be after two unmanned suborbital flights of CSM (AS-201 and AS-202). Then AS-205 CSM manned orbital and AS-206 LM (the Apollo Lunar Module) unmanned flights followed by dual AS-278 mission of AS-207 CSM and AS-208 LM (started on Saturn IB separately for docking) were scheduled. Later AS-205 mission was canceled, AS-278 dual mission was reassigned as AS-258 and AS-278 CSM+LM common manned mission on Saturn V was planned.

Due to pre-launch fire of Apollo 1 and death of its crew, the manned missions were postponed and more unmanned missions were added for Apollo improvements. The only unmanned missions to be publicly designated as "Apollo" followed by a sequence number were Apollo 4, Apollo 5 and Apollo 6.^[30] The simple numbering was started at "4" to follow the three Apollo-Saturn IB flights (AS-201 to AS-202), though all subsequent flights kept the "AS" designations: AS-204 (redesigned from AS-206) and following for Saturn IB flights, and AS-501 and following for Saturn V flights.

Apollo launches, 1–6: unmanned, 7–17: manned (Click on image to read about mission)

Apollo 4 (AS-501) was the first unmanned test flight of the Saturn V launch vehicle, carrying a CSM. Launched on November 9, 1967, Apollo 4 exemplified George Mueller'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 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.^[31] 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.

Location of soft landings on the Moon. Dates in UTC.

Apollo 5 (AS-204) was the first unmanned test flight of 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 (AS-502) was the last unmanned Saturn V flight, launched on April 4, 1968. It carried a CSM and a LM 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 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[link]

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.

The first planned manned mission was an Earth orbital test of the Block I CSM launched with a Saturn IB was designated AS-204, or Apollo 1, originally planned for late in 1966, but plagued by delays until February 21, 1967. A second Block I CSM orbital flight, AS-205, was originally planned but canceled in late 1966. The next manned mission was planned as a dual launch of the Block II CSM (originally AS-207, then changed to AS-205) with AS-208 launching an unmanned LM to which the astronauts in the CSM would dock. This mission was first designated AS-258, and later as AS-278. This would be followed by the first manned launch of both spacecraft on a Saturn V in a high Earth orbital test.

These plans had to be revised after the January 27, 1967 fire which killed the Apollo 1 crew in a pre-launch test. Manned flight of the Block I CSM was canceled, and the program concentrated on unmanned testing of the Saturn V and LM while safety improvements were made to the Block II CSM which would be used exclusively in manned flight. The AS-278 mission was revised to use a Saturn V in a single launch instead of two Saturn IBs.

Apollo 7, 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 CSM as in former planned AS-204 Apollo 1 mission. It was the first manned launch of the Saturn IB launch vehicle and the first three-man American space mission.

Lunar Roving Vehicle used on Apollos 15–17

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 during Christmas. The original idea for this switch was the brainchild of George Low, 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 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. Soviets undertook partially successful unmanned Zond 5 and Zond 6 missions and could near December, 8 but have not decided to launch almost ready manned Zond mission before Apollo 8.^{[clarification needed]}

Plaque left on the Moon by Apollo 17

This was followed by the first orbital manned LM flight on Apollo 9 (as former planned AS-278 mission and with the original Apollo 8 crew), and the lunar "dress rehearsal" Apollo 10 which took the LM to within 50,000 feet (15 km) of the surface, but did not land. The first landing was achieved on Apollo 11 on July 20, 1969.

That's one small step for [a] man, one giant leap for mankind.

—Neil Armstrong, just after stepping onto the Moon's surface^[32]

Apollo 12 made a precision landing near the Surveyor 3 unmanned lunar probe, which had landed in April 1967. The Apollo 13 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 Rovers.

Apollo 17, 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[link]

Astronaut Group 3 – all ten surviving members flew in Apollo missions

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 1968 and December 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[link]

Mission rules specified that, in most circumstances, only one person in the Mission Control Center 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 and Gemini 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.

Samples returned[link]

The most famous of the Moon rocks recovered, the Genesis Rock, returned from Apollo 15.		Ferroan Anorthosite Moon rock, returned from Apollo 16.

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 in Houston. The only sources of Moon rocks on Earth are those collected from the Apollo program, the former Soviet Union's Luna missions, and lunar meteorites.

The rocks collected from the Moon are extremely old compared to rocks found on Earth, as measured by radiometric dating techniques. They range in age from about 3.2 billion years old for the basaltic samples derived from the lunar mare, to about 4.6 billion years for samples derived from the highlands crust.^[33] As such, they represent samples from a very early period in the development of the Solar System that is largely missing from Earth. One important rock found during the Apollo Program was the Genesis Rock, retrieved by astronauts James Irwin and David Scott during the Apollo 15 mission. This rock, called anorthosite, is composed almost exclusively of the calcium-rich feldspar mineral anorthite, and is believed to be representative of the highland crust. A geochemical component called KREEP 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).

Almost all the rocks show evidence for having been affected by impact processes. For instance, many samples appear to be pitted with micrometeoroid 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 brecciated as a result of being subjected to multiple impact events.

Analysis of composition of the lunar samples support the giant impact hypothesis, that the Moon was created through a "giant impact" of a large astronomical body with the Earth.^[34]

Program costs and cancellation[link]

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 judgment to change the estimate to $20 billion before giving it to Vice President Johnson.^[35]

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:^[36]

• 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.^[37] 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.^[38]

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 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 report, A Budgetary Analysis of NASA’s New Vision for Space, September 2004.^[35] The Space Review estimated in 2010 the cost of Apollo from 1959 to 1973 as $20.4 billion, or $109 billion in 2010 dollars. Each lunar landing thus cost $18 billion in 2010 dollars.^[39]

Canceled missions[link]

Originally three additional lunar landing missions had been planned, as Apollo 18 through Apollo 20. In light of the drastically shrinking NASA 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, 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, George C. Marshall Space Center in Huntsville, Alabama, Michoud Assembly Facility in New Orleans, Louisiana, and Lyndon B. Johnson Space Center in Houston, Texas.

Apollo Applications Program[link]

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, 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 space station and the Apollo–Soyuz Test Project.

Skylab's fuselage was constructed from the second stage of a Saturn IB, and the station was equipped with the Apollo Telescope Mount, 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 24, 1975. NASA's next manned mission would not be until STS-1 in 1981.

Recent observations[link]

“There the [Apollo 11] lunar module sits, parked just where it landed 40 years ago, as if it still really were 40 years ago and all the time since merely imaginary.” –The New York Times^[40]

In 2008, Japan Aerospace Exploration Agency's SELENE probe observed evidence of the halo surrounding the Apollo 15 lunar module blast crater while orbiting above the lunar surface.^[41] In 2009, NASA's robotic Lunar Reconnaissance Orbiter, while orbiting 50 kilometres (31 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.^[42][43]

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

[T]here’s something terribly wistful about these photographs of the Apollo landing sites. The detail is such that if Neil Armstrong were walking there now, we could make him out, make out his footsteps even, like the astronaut footpath clearly visible in the photos of the Apollo 14 site. Perhaps the wistfulness is caused by the sense of simple grandeur in those Apollo missions. Perhaps, too, it’s a reminder of the risk we all felt after the Eagle had landed – the possibility that it might be unable to lift off again and the astronauts would be stranded on the Moon. But it may also be that a photograph like this one is as close as we’re able to come to looking directly back into the human past.^[40]

Proposed future lunar landing missions, such as the Google Lunar X Prize, intended to record close-up images of the Apollo Lunar Modules and other artificial objects on the surface.^[44]

Legacy[link]

Science and engineering[link]

The Apollo program, specifically the lunar landings, has been called the greatest technological achievement in human history.^[45][46] The program stimulated many areas of technology. The flight computer design used in both the lunar and command modules was, along with the Minuteman Missile System, the driving force behind early research into integrated circuits. The fuel cell developed for this program was the first practical fuel cell. Computer-controlled machining (CNC) was pioneered in fabricating Apollo structural components.

Cultural impact[link]

"Everything that I ever knew – my life, my loved ones, the Navy – everything, the whole world was behind my thumb." –James Lovell

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, 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 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 moonwalk.^[47]

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 astronauts, is The Blue Marble (right). These photographs have also motivated some people toward environmentalism.^[48]

"We went to explore the Moon, and in fact discovered the Earth." –Eugene Cernan

Many astronauts and cosmonauts have commented on the profound effects that seeing Earth from space has had on them;^[49] the 24 astronauts who traveled to the Moon are the only humans to have observed Earth from beyond low Earth orbit, 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 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.^[50]

Apollo 11 broadcast data restoration project[link]

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.^[51] 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.^[52]

We're all saddened that they're not there. We all wish we had 20-20 hindsight. I don't think anyone in the NASA organization did anything wrong, I think it slipped through the cracks, and nobody's happy about it.

—Dick Nafzger, TV Specialist, NASA Goddard Space Flight Center^[52]

The Moon landing data was recorded by a special Apollo TV camera 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 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.^[52]

So I don't believe that the tapes exist today at all. It was a hard thing to accept. But there was just an overwhelming amount of evidence that led us to believe that they just don't exist anymore. And you have to accept reality.

—Stan Lebar, Lunar Camera Designer, Westinghouse Electric Corporation^[52]

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.^[53] The images were from tapes in Australia, the CBS News archive, and kinescope 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.^[53]

Documentaries[link]

Numerous documentary films cover the Apollo program and the space race, including:

• Moonwalk One (1970)
• For All Mankind (1989)
• Moon Shot (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 (2005)
• In the Shadow of the Moon (2007)
• When We Left Earth: The NASA Missions (miniseries) (2008)
• James May on the Moon (documentary commemorating 40 years since the landings) (2009)
• NASA's Story

See also[link]

	Spaceflight portal
	Moon portal

• Apollo 1 – unflown mission
• Apollo 11 flight to the Moon
• Apollo 18, Apollo 19, Apollo 20 – canceled missions
• Apollo TV camera
• AS-201, AS-202, AS-203, Apollo 4, Apollo 5, Apollo 6 – unmanned missions
• List of man-made objects on the Moon
• List of megaprojects
• Lockheed Propulsion Company
• Pad Abort Tests
• Soviet manned lunar programs
• Splashdown (spacecraft landing)

Notes[link]

References[link]

Further reading[link]

External links[link]

Wikimedia Commons has media related to: Apollo missions

• Official Apollo program web page
• Apollo photo gallery at NASA Human Spaceflight page (includes videos/animations)
• Audio recording and transcript of President John F. Kennedy, NASA administrator James Webb et al. discussing the Apollo agenda (White House Cabinet Room, November 21, 1962)
• U.S. Spaceflight History- Apollo Program
• Apollo Image Atlas almost 25,000 lunar images, Lunar and Planetary Institute
• Project Apollo at NASA History Division
• The Apollo Lunar Surface Journal
• How Apollo Has Influenced Society
• The Apollo Flight Journal
• Project Apollo Drawings and Technical Diagrams
• Apollo Program Summary Report (Technical)
• The Apollo Program (National Air and Space Museum)
• Apollo 35th Anniversary Interactive Feature (in Flash)
• Exploring the Moon: Apollo Missions
• Apollo Archive – large repository of information about the Apollo program.
• Apollo Flight Film Archive – repository of scanned Apollo flight film (in high resolution).
• NASA History Series Publications (many of which are on-line)
• Apollo's Contributions to Society
• The short film "Time of Apollo (1975)" is available for free download at the Internet Archive [more]

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Neil Armstrong
USAF / NASA Astronaut
Nationality	American
Status	Retired
Born	(1930-08-05) August 5, 1930 (age 81)[1] Wapakoneta, Ohio, U.S.
Previous occupation	Naval aviator, test pilot
Time in space	8 days, 14 hours, 12 minutes and 31 seconds
Selection	1958 Man In Space Soonest 1960 Dyna-Soar 1962 NASA Group 2
Total EVAs	1
Total EVA time	2 hours 31 minutes
Missions	Gemini 8, Apollo 11
Mission insignia
Awards

Neil Alden Armstrong (born August 5, 1930) 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.

Before becoming an astronaut, Armstrong was in the United States Navy and served in the Korean War. After the war, he served as a test pilot at the National Advisory Committee for Aeronautics (NACA) High-Speed Flight Station, now known as the Dryden Flight Research Center, where he flew over 900 flights in a variety of aircraft. As a research pilot, Armstrong served as project pilot on the F-100 Super Sabre A and C variants, F-101 Voodoo, and the Lockheed F-104A Starfighter. He also flew the Bell X-1B, Bell X-5, North American X-15, F-105 Thunderchief, F-106 Delta Dart, B-47 Stratojet, KC-135 Stratotanker, and was one of eight elite pilots involved in the paraglider research vehicle program (Paresev). He graduated from Purdue University and the University of Southern California.

A participant in the U.S. Air Force's Man In Space Soonest and X-20 Dyna-Soar human spaceflight programs, Armstrong joined the NASA Astronaut Corps in 1962. His first spaceflight was the NASA Gemini 8 mission in 1966, for which he was the command pilot, becoming one of the first U.S. civilians to fly in space.^{[citation needed]} On this mission, he performed the first manned docking of two spacecraft with pilot David Scott. Armstrong's second and last spaceflight was as mission commander of the Apollo 11 moon landing mission on July 20, 1969. On this mission, Armstrong and Buzz Aldrin descended to the lunar surface and spent 2½ hours exploring while Michael Collins remained in orbit in the Command Module. Armstrong was awarded the Presidential Medal of Freedom by Richard Nixon along with Collins and Aldrin, the Congressional Space Medal of Honor by President Jimmy Carter in 1978, and the Congressional Gold Medal in 2009.

Early years[link]

Neil Armstrong was born in Wapakoneta, Ohio, to Stephen Koenig Armstrong and Viola Louise Engel.^[2][3] He is of Scots-Irish and German descent, and had two younger siblings, June and Dean. Stephen Armstrong worked as an auditor^[4] for the Ohio state government, and the family moved around the state repeatedly in the 15 years following Armstrong's birth, living in 20 different towns. His love for flying grew during this time, having gotten off to an early start when his father took 2-year-old Neil to the Cleveland Air Races. On July 20, 1936, when he was 6, he experienced his first airplane flight in Warren, Ohio, when he and his father took a ride in a Ford Trimotor (aka the "Tin Goose").^[5] His father's last forced move was to Wapakoneta (Auglaize County) in 1944, where Neil attended Blume High School. Armstrong began taking flying lessons at the county airport, and was just 15 when he earned his flight certificate, before he had a driver's license. Armstrong was active in the Boy Scouts and he eventually earned the rank of Eagle Scout. As an adult, he was recognized by the Boy Scouts of America with their Distinguished Eagle Scout Award and Silver Buffalo Award.^[6] On July 18, 1969, while flying towards the Moon inside the Columbia, he greeted the Scouts: "I'd like to say hello to all my fellow scouts and scouters at Farragut State Park in Idaho having a National Jamboree there this week; and Apollo 11 would like to send them best wishes". Houston: "Thank you, Apollo 11. I'm sure that, if they didn't hear that, they'll get the word through the news. Certainly appreciate that."^[7]

In 1947, Armstrong began studying aerospace engineering at Purdue University, where he was a member of Phi Delta Theta^[8] and Kappa Kappa Psi.^[9] He was only the second person in his family to attend college, and was also accepted to the Massachusetts Institute of Technology (MIT), but the only engineer he knew (who had attended MIT) dissuaded him from attending, telling Armstrong that it was not necessary to go all the way to Cambridge, Massachusetts, for a good education.^[10] His college tuition was paid for under the Holloway Plan – successful applicants committed to two years of study, followed by three years of service in the United States Navy, then completion of the final two years of the degree. At Purdue, he earned average marks in his subjects, with a GPA that rose and fell during eight semesters. He was awarded a Bachelor of Science degree in aeronautical engineering from Purdue University in 1955, and, from the University of Southern California in 1970, a Master of Science degree in aerospace engineering.^[11] Armstrong holds honorary doctorates from a number of universities.^[12]

Navy service[link]

Armstrong's call-up from the Navy arrived on January 26, 1949, which required him to report to Naval Air Station Pensacola for flight training. This lasted almost 18 months, during which he qualified for carrier landing aboard the USS Cabot and USS Wright. On August 16, 1950, two weeks after his 20th birthday, Armstrong was informed by letter he was a fully qualified Naval Aviator.^[13]

His first assignment was to Fleet Aircraft Service Squadron 7 at NAS San Diego (now known as NAS North Island). Two months later he was assigned to Fighter Squadron 51 (VF-51), an all-jet squadron, and made his first flight in a jet, an F9F-2B Panther, on January 5, 1951. In June, he made his first jet carrier landing on the USS Essex and was promoted the same week from midshipman to ensign. By the end of the month, the Essex had set sail with VF-51 aboard, bound for Korea, where they would act as ground-attack aircraft.^[14]

Armstrong first saw action in the Korean War on August 29, 1951, as an escort for a photo reconnaissance plane over Songjin.^[15] On September 3, 1951, Armstrong flew armed reconnaissance over the primary transportation and storage facilities south of the village of Majon-ni, west of Wonsan; while he was making a low bombing run at about 350 mph (560 km/h), Armstrong's F9F Panther was hit by anti-aircraft fire. While trying to regain control, Armstrong collided with a pole at a height of about 20 feet (6.1 m), which sliced off an estimated three feet of the Panther's right wing.^[16] Armstrong was able to fly the plane back to friendly territory, but due to the loss of the aileron, ejection was his only safe option. He planned to eject over water and await rescue by navy helicopters, and therefore flew to an airfield near Pohang but instead of achieving the desired rescue from the water, his ejection seat was blown back over land.^[17] A jeep driven by a room-mate from flight school picked Armstrong up; it is unknown what happened to the wreckage of No. 125122 F9F-2.^[18]

Armstrong flew 78 missions over Korea for a total of 121 hours in the air, most of which were in January 1952. He received the Air Medal for 20 combat missions, a Gold Star for the next 20, and the Korean Service Medal and Engagement Star.^[19] Armstrong left the navy at the age of 22 on August 23, 1952, and became a Lieutenant, Junior Grade in the United States Naval Reserve. He resigned his commission in the Naval Reserve on October 21, 1960.^[20]

College years[link]

After his service with the Navy, Armstrong returned to Purdue, where his best grades came in the four semesters following his return from Korea. His final GPA was 4.8 out of 6.0.^[21] He pledged the Phi Delta Theta fraternity after his return, where he wrote and co-directed their musical as part of the all-student revue, was also a member of Kappa Kappa Psi National Honorary Band Fraternity, and a baritone player in the Purdue All-American Marching Band. Armstrong graduated with a bachelor's degree in aeronautical engineering in 1955.^[20]

While at Purdue, he met Janet Elizabeth Shearon, who was majoring in home economics. According to the two there was no real courtship, and neither can remember the exact circumstances of their engagement, except that it occurred while Armstrong was working at the NACA's Lewis Flight Propulsion Laboratory. They were married on January 28, 1956 at the Congregational Church in Wilmette, Illinois. When he moved to Edwards Air Force Base, he lived in the bachelor quarters of the base, while Janet lived in the Westwood district of Los Angeles. After one semester, they moved into a house in Antelope Valley. Janet never finished her degree, a fact she regretted later in life.^[22]

The couple had three children together – Eric, Karen, and Mark.^[23] In June 1961, Karen was diagnosed with a malignant tumor of the middle part of her brain stem; X-ray treatment slowed its growth but her health deteriorated to the point where she could no longer walk or talk. Karen died of pneumonia, related to her weakened health, on January 28, 1962.^[24]

Armstrong later completed his master of science degree in aeronautical engineering at the University of Southern California.^[1]

Test pilot[link]

A portrait of Armstrong taken November 20, 1956 while he was a test pilot at the NACA High-Speed Flight Station at Edwards Air Force Base, California.

Following his graduation from Purdue, Armstrong decided to become an experimental research test pilot. He applied at the National Advisory Committee for Aeronautics High-Speed Flight Station at Edwards Air Force Base; although they had no open positions they did forward his application to the Lewis Flight Propulsion Laboratory in Cleveland, Ohio, where Armstrong began working at Lewis Field in March 1955.^[25] Armstrong's stint at Cleveland lasted a couple of months, and by July 1955, he had returned to Edwards AFB for his new job.^[26]

On his first day at Edwards, Armstrong was tasked his first assignments, which were to pilot chase planes during releases of experimental aircraft from modified bombers. He also flew the modified bombers, and on one of these missions had his first flight incident at Edwards. Armstrong was in the right-hand seat of a B-29 Superfortress on March 22, 1956,^[27] which was to air-drop a Douglas Skyrocket D-558-2. Armstrong sat the right-hand seat pilot while the left-hand seat commander, Stan Butchart, flew the B-29.^[28]

As they ascended to 30,000 ft (9 km), the number four engine stopped and the propeller began windmilling (rotating freely) in the airstream. Hitting the switch that would stop the propeller spinning, Butchart found the propeller slowed but then started spinning again, this time even faster than the other engines; if it spun too fast, it would break apart. Their aircraft needed to hold an airspeed of 210 mph (338 km/h) to launch its Skyrocket payload, and the B-29 could not land with the Skyrocket still attached to its belly. Armstrong and Butchart brought the aircraft into a nose-down alignment to increase speed, then launched the Skyrocket. At the very instant of launch, the number four engine propeller disintegrated. Pieces of it careened through part of the number three engine and hit the number two engine. Butchart and Armstrong were forced to shut down the number three engine, due to damage, and the number one engine, due to the torque it created. They made a slow, circling descent from 30,000 ft (9,000 m) using only the number two engine, and landed safely.^[29]

Armstrong's first flight in a rocket plane was on August 15, 1957, in the Bell X-1B, to an altitude of 11.4 miles (18.3 km). The nose landing gear broke on landing, which had happened on about a dozen previous flights of the Bell X-1B due to the aircraft's design.^[30] He later flew the North American X-15; Armstrong would fly the aircraft seven times before September 1962, and during his penultimate X-15 flight, he reached an altitude of 207,500 feet (63.2 km).^[30]

Armstrong was involved in several incidents that went down in Edwards folklore and/or were chronicled in the memoirs of colleagues. The first was an X-15 flight on April 20, 1962, when Armstrong tested a self-adjusting control system. He flew to a height of 207,000 ft (63 km), (the highest he flew before Gemini 8), but he held the aircraft nose up too long during descent, and the X-15 bounced off the atmosphere back up to 140,000 ft (43 km). At that altitude, the atmosphere is so thin that aerodynamic surfaces have almost no effect. He flew past the landing field at Mach 3 (2,000 mph, or 3,200 km/h), over 100,000 ft (30.5 km) altitude, and ended up 40 miles (64 km) south of Edwards (legend has it that he flew as far as the Rose Bowl). After sufficient descent, he turned back toward the landing area, and barely managed to land without striking Joshua trees at the south end. It was the longest X-15 flight in both time and distance of the ground track.^[31]

Four days later, Armstrong was involved in a second incident, when he flew for the only time with Chuck Yeager. Their job, flying a T-33 Shooting Star, was to evaluate Smith Ranch Dry Lake for use as an emergency landing site for the X-15. In his autobiography, Yeager wrote that he knew the lake bed was unsuitable for landings after recent rains, but Armstrong insisted on flying out anyway. As they attempted a touch-and-go, the wheels became stuck and they had to wait for rescue. Armstrong tells a different version of events, where Yeager never tried to talk him out of it and they made a first successful landing on the east side of the lake. Then Yeager told him to try again, this time a bit slower. On the second landing they became stuck and according to Armstrong, Yeager was in fits of laughter.^[32]

Armstrong stands next to the X-15 ship#1 after a research flight.

Many of the test pilots at Edwards praised Armstrong's engineering ability. Milt Thompson said he was "the most technically capable of the early X-15 pilots." Bill Dana said Armstrong "had a mind that absorbed things like a sponge." Those who flew for the Air Force tended to have a different opinion, especially people like Chuck Yeager and Pete Knight who did not have engineering degrees. Knight said that pilot-engineers flew in a way that was "more mechanical than it is flying," and gave this as the reason why some pilot-engineers got into trouble: their flying skills did not come naturally.^[33]

On May 21, 1962, Armstrong was involved in what Edwards' folklore called the "Nellis Affair". He was sent in an F-104 Starfighter to inspect Delamar Lake, again for emergency landings. He misjudged his altitude, and also did not realize that the landing gear had not fully extended. As he touched down, the landing gear began to retract. Armstrong applied full power to abort the landing, but the ventral fin and landing gear door struck the ground, which damaged the radio and released hydraulic fluid. Without radio communication, Armstrong flew to Nellis Air Force Base, past the control tower, and waggled his wings, the signal for a no-radio approach. The loss of hydraulic fluid caused the tail-hook to release, and upon landing he caught the arresting wire attached to an anchor chain, and careened along the runway dragging the chain. It took thirty minutes to clear the runway and rig an arresting cable. Armstrong telephoned Edwards and asked for someone to collect him. Milt Thompson was sent in an F-104B, the only two-seater available, but a plane Thompson had never flown. With great difficulty, Thompson made it to Nellis, but a strong crosswind caused a hard landing and the left main tire suffered a blowout. The runway was again closed to clear it, and Bill Dana was sent to Nellis in a T-33 Shooting Star, but he almost landed long — and the Nellis base operations office decided that it would be best to find the three NASA pilots ground transport back to Edwards, to avoid any further problems.^[34]

Armstrong made seven flights in the X-15. He reached a top altitude of 207,500 ft (63.2 km) in the X-15-3,^[35] and a top speed of Mach 5.74 (4,000 mph or 6,615 km/h) in the X-15-1; he left the Dryden Flight Research Center with a total of 2,400 flying hours.^[36] Over his career, he has flown more than 200 different models of aircraft.^[11]

Astronaut career[link]

Armstrong in an early Gemini spacesuit

There was no defining moment in Armstrong's decision to become an astronaut. In 1958, he was selected for the U.S. Air Force's Man In Space Soonest program. In November 1960 Armstrong was chosen as part of the pilot consultant group for the X-20 Dyna-Soar, a military space plane, and on March 15, 1962 he was named as one of six pilot-engineers who would fly the space plane when it got off the design board.^[37]

In the months after the announcement that applications were being sought for the second group of NASA astronauts, he became more and more excited about the prospects both of the Apollo program and of investigating a new aeronautical environment. Armstrong's astronaut application had arrived about a week past the June 1, 1962 deadline, but Dick Day, with whom Armstrong had worked closely at Edwards, worked at the Manned Spacecraft Center, saw the late arrival of the application, and slipped it into the pile before anyone noticed.^[38] At Brooks City-Base at the end of June he underwent a medical exam that many of the applicants described as painful and at times seemingly pointless.^[39]

Deke Slayton called Armstrong on September 13, 1962 and asked if he was interested in joining the NASA Astronaut Corps as part of what the press dubbed "the New Nine"; without hesitation, Armstrong said yes. The selections were kept secret until three days later, although newspaper reports had been circulating since the middle of summer that year that he would be selected as the "first civilian astronaut".^[40] Armstrong was one of two civilian pilots selected for the second group, the other being Elliott See who, like Armstrong, was a naval aviator.^[41] Armstrong did not become the first civilian to fly in space, as the Russians had launched Vostok 6 on June 16, 1963 with Valentina Tereshkova, a textile worker and amateur parachutist, aboard.^[42]

Gemini program[link]

[edit] Gemini 8

The crew assignments for Gemini 8 were announced on September 20, 1965, with Armstrong as Command Pilot and David Scott as Pilot. Scott was the first member of the third group of astronauts to receive a prime crew assignment. The mission launched on March 16, 1966; it was to be the most complex yet, with a rendezvous and docking with the unmanned Agena target vehicle, the second American extra-vehicular activity by Scott. In total the mission was planned to last 75 hours and 55 orbits. After the Agena lifted off at 10 am EST, the Titan II carrying Armstrong and Scott ignited at 11:41:02 am EST, putting them into an orbit from where they would chase the Agena.^[43]

Recovery of the Gemini 8 spacecraft from the western Pacific Ocean

The rendezvous and first ever docking between two spacecraft was successfully completed after 6.5 hours in orbit.^[44] Contact with the crew was intermittent due to the lack of tracking stations covering their entire orbits. Out of contact with the ground, the docked spacecraft began to roll, which Armstrong attempted to correct with the Orbital Attitude and Maneuvering System (OAMS) of the Gemini spacecraft. Following the earlier advice of Mission Control, they undocked, but found that the roll increased dramatically to the point where they were turning about once per second, which meant the problem was in their Gemini's attitude control. Armstrong decided the only course of action was to engage the Reentry Control System (RCS) and turn off the OAMS. Mission rules dictated that once this system was turned on, the spacecraft would have to reenter at the next possible opportunity. It was later thought that damaged wiring made one of the thrusters become stuck on.^[45]

Throughout the astronaut office there were a few people, most notably Walter Cunningham, who publicly stated that Armstrong and Scott had ignored the malfunction procedures for such an incident, and that Armstrong could have salvaged the mission if he had turned on only one of the two RCS rings and saved the other for mission objectives. These criticisms were unfounded – no malfunction procedures were written and it was only possible to turn on both RCS rings, not one or the other. Gene Kranz wrote, "the crew reacted as they were trained, and they reacted wrong because we trained them wrong." The mission planners and controllers had failed to realize that when two spacecraft are docked together they must be considered to be one spacecraft.^[46]

Armstrong himself was depressed^[47] that the mission had been cut short, which cancelled most mission objectives and robbed Scott of his EVA.

[edit] Gemini 11

The last crew assignment for Armstrong during the Gemini program was as backup Command Pilot for Gemini 11, announced two days after the landing of Gemini 8. Having already trained for two flights, Armstrong was quite knowledgeable about the systems and was more in a teaching role^[48] for the rookie backup Pilot, William Anders. The launch was on September 12, 1966^[49] with Pete Conrad and Dick Gordon on board, who successfully completed the mission objectives, while Armstrong served as CAPCOM.

Following the flight, President Lyndon B. Johnson asked Armstrong and his wife to take part in a 24-day goodwill tour of South America.^[50] Also on the tour, which took in 11 countries and 14 major cities, were Dick Gordon, George Low, their wives, and other government officials. In Paraguay, Armstrong impressed dignitaries by greeting them in their local language, Guarani;^[51] in Brazil he talked about the exploits of the Brazilian-born Alberto Santos-Dumont, who was regarded as having beaten the Wright brothers with the first flying machine with his 14-bis.^[52]

Apollo program[link]

On January 27, 1967, the date of the Apollo 1 fire, Armstrong was in Washington, D.C. with Gordon Cooper, Dick Gordon, Jim Lovell and Scott Carpenter for the signing of the United Nations Outer Space Treaty. The astronauts chatted with the assembled dignitaries until 6:45 pm Carpenter went to the airport, and the others returned to the Georgetown Inn, where they each found messages to phone the Manned Spacecraft Center. They learned of the deaths of Gus Grissom, Ed White and Roger Chaffee during these telephone calls. Armstrong and the group spent the rest of the night drinking scotch and discussing what had happened.^[53]

On April 5, 1967, the same day the Apollo 1 investigation released its report on the fire, Armstrong assembled with 17 other astronauts for a meeting with Deke Slayton. The first thing Slayton said was, "The guys who are going to fly the first lunar missions are the guys in this room."^[54] According to Eugene Cernan, Armstrong showed no reaction to the statement. To Armstrong it came as no surprise – the room was full of veterans of Project Gemini, the only people who could fly the lunar missions. Slayton talked about the planned missions and named Armstrong to the backup crew for Apollo 9, which at that stage was planned to be a medium Earth orbit test of the Lunar Module-Command/Service Module combination. After design and manufacturing delays in the Lunar Module (LM), Apollo 9 and Apollo 8 swapped crews. Based on the normal crew rotation scheme, Armstrong would command Apollo 11.^[55]

To attempt to give the astronauts experience with how the LM would fly on its final landing descent, NASA commissioned Bell Aircraft to build two Lunar Landing Research Vehicles, later augmented with three Lunar Landing Training Vehicles (LLTV). Nicknamed the "Flying Bedsteads", they simulated the Moon's one-sixth of Earth's gravity by using a turbofan engine to support the remaining five-sixths of the craft's weight. On May 6, 1968, about 100 feet (30m) above the ground, Armstrong's controls started to degrade and the LLTV began banking.^[56] He ejected safely (later analysis would suggest if he had ejected 0.5 seconds later, his parachute would not have opened in time). His only injury was from biting his tongue. Even though he was nearly killed on one, Armstrong maintains that without the LLRV and LLTV, the lunar landings would not have been successful as they gave commanders valuable experience in the behavior of lunar landing craft.^[57]

Apollo 11[link]

The Apollo 11 crew portrait. Left to right are Armstrong, Michael Collins, and Buzz Aldrin.

After Armstrong served as backup commander for Apollo 8, Slayton offered him the post of commander of Apollo 11 on December 23, 1968, as 8 orbited the Moon.^[58] In a meeting that was not made public until the publication of Armstrong's biography in 2005, Slayton told him that although the planned crew was Armstrong as commander, lunar module pilot Buzz Aldrin and command module pilot Michael Collins, he was offering the chance to replace Aldrin with Jim Lovell. After thinking it over for a day, Armstrong told Slayton he would stick with Aldrin, as he had no difficulty working with him and thought Lovell deserved his own command. Replacing Aldrin with Lovell would have made Lovell the Lunar Module Pilot, unofficially the lowest ranked member, and Armstrong could not justify placing Lovell, the commander of Gemini 12, in the number 3 position of the crew.^[59]

A March 1969 meeting between Slayton, George Low, Bob Gilruth, and Chris Kraft determined that Armstrong would be the first person on the Moon, in some part because NASA management saw Armstrong as a person who did not have a large ego.^[60] A press conference held on April 14, 1969 gave the design of the LM cabin as the reason for Armstrong being first; the hatch opened inwards and to the right, making it difficult for the lunar module pilot, on the right-hand side, to egress first. Slayton added, "Secondly, just on a pure protocol basis, I figured the commander ought to be the first guy out. . . . I changed it as soon as I found they had the time line that showed that. Bob Gilruth approved my decision."^[61] At the time of their meeting, the four men did not know about the hatch issue. The first knowledge of the meeting outside the small group came when Kraft wrote his 2001 autobiography.^[62]

On July 16, 1969, Armstrong received a crescent moon carved out of Styrofoam from the pad leader, Guenter Wendt, who described it as a key to the Moon. In return, Armstrong gave Wendt a ticket for a "space taxi" "good between two planets".^[63]

Voyage to the Moon[link]

Aldrin took this picture of Armstrong in the cabin after the completion of the EVA.

During the Apollo 11 launch, Armstrong's heart reached a top rate of 110 beats per minute.^[64] He found the first stage to be the loudest – much noisier than the Gemini 8 Titan II launch – and the Apollo CSM was relatively roomy compared to the confinement of the Gemini capsule. This ability to move around was suspected to be the cause of space sickness that had hit members of previous crews, but none of the Apollo 11 crew suffered from it; Armstrong was especially happy, as he had been prone to motion sickness as a child and could experience nausea after doing long periods of aerobatics.^[65]

The objective of Apollo 11 was to land safely rather than to touch down with precision on a particular spot. Three minutes into the lunar descent burn Armstrong noted that craters were passing about two seconds too early, which meant the Eagle would probably touch down beyond the planned landing zone by several miles.^[66] As the Eagle's landing radar acquired the surface, several computer error alarms appeared. The first was a code 1202 alarm, and even with their extensive training Armstrong or Aldrin were not aware of what this code meant. However, they promptly received word from CAPCOM in Houston that the alarms were not a concern; the 1202 and 1201 alarms were caused by an executive overflow in the lunar module computer. As described by Buzz Aldrin in the documentary In the Shadow of the Moon, the overflow condition was caused by his own counter-checklist choice of leaving the docking radar on during the landing process, so the computer had to process unnecessary radar data and did not have enough time to execute all tasks, dropping lower-priority ones. Aldrin stated that he did so with the objective of facilitating re-docking with the CM should an abort become necessary, not realizing that it would cause the overflow condition.^{[citation needed]}

When Armstrong noticed they were heading towards a landing area which he believed was unsafe, he took over manual control of the LM, and attempted to find an area which seemed safer, which took longer than expected, and longer than most simulations had taken.^[67] For this reason, there was concern from mission control that the LM was running low on fuel.^[68] Upon landing, Aldrin and Armstrong believed they had about 40 seconds worth of fuel to left, which included the 20 seconds worth of fuel which had to be saved in the event of an abort.^[69] During training, Armstrong had landed the LLTV with less than 15 seconds left on several occasions, and he was also confident the LM could survive a straight-down fall from 50 feet (15 m) if needed. Analysis after the mission showed that at touchdown there were 45 to 50 seconds of propellant burn time left.^[70]

The landing on the surface of the moon occurred at 20:17:39 UTC on July 20, 1969.^[71] When a sensor attached to the legs of the still hovering Lunar Module made lunar contact, a panel light inside the LM lit up and Aldrin called out, "Contact light." As the LM settled on the surface Aldrin then said, "Okay. Engine stop," and Armstrong said, "Shutdown." The first words Armstrong intentionally spoke to Mission Control and the world from the lunar surface were, "Houston, Tranquility Base here. The Eagle has landed." Aldrin and Armstrong celebrated with a brisk handshake and pat on the back before quickly returning to the checklist of tasks needed to ready the lunar module for liftoff from the Moon should an emergency unfold during the first moments on the lunar surface.^[72][73][74] During the critical landing, the only message from Houston was "30 seconds", meaning the amount of fuel left. When Armstrong had confirmed touch down, Houston expressed their worries during the manual landing as "You got a bunch of guys about to turn blue. We're breathing again".^[69]

First Moon walk[link]

	"That's one small step for [a] man, one giant leap for mankind"
Problems listening to this file? See media help.

Although the official NASA flight plan called for a crew rest period before extra-vehicular activity, Armstrong requested that the EVA be moved to earlier in the evening, Houston time. Once Armstrong and Aldrin were ready to go outside, Eagle was depressurized, the hatch was opened and Armstrong made his way down the ladder first.

Armstrong describes the lunar surface.

At the bottom of the ladder, Armstrong said "I'm going to step off the LEM now" (referring to the Apollo Lunar Module). He then turned and set his left boot on the surface at 2:56 UTC July 21, 1969,^[75] then spoke the famous words "That's one small step for [a] man, one giant leap for mankind."^[76]

Armstrong had decided on this statement following a train of thought that he had had after launch and during the hours after landing.^[77] Armstrong said later that he accidentally dropped the "a", from his remark, rendering the phrase a contradiction (as man in such use is synonymous with mankind).^[76] Armstrong later said he "would hope that history would grant me leeway for dropping the syllable and understand that it was certainly intended, even if it was not said – although it might actually have been".^[78]

It has since been claimed that acoustic analysis of the recording reveals the presence of the missing "a";^[76][79] Peter Shann Ford, an Australia-based computer programmer, conducted a digital audio analysis and claims that Armstrong did, in fact, say "a man", but the "a" was inaudible due to the limitations of communications technology of the time.^[76][80][81] Ford and James R. Hansen, Armstrong's authorized biographer, presented these findings to Armstrong and NASA representatives, who conducted their own analysis.^[82] The article by Ford, however, is published on Ford's own web site rather than in a peer-reviewed scientific journal, and linguists David Beaver and Mark Liberman at Language Log were skeptical of Ford's claims.^[83] Armstrong has expressed his preference that written quotations include the "a" in parentheses.^[84]

When Armstrong made his proclamation, Voice of America was rebroadcast live via the BBC and many other stations worldwide. The estimated global audience at that moment was 450 million listeners,^[85] out of a then estimated world population of 3.631 billion people.^[86]

Armstrong prepares to take the first step on the Moon.

About 20 minutes after the first step, Aldrin joined Armstrong on the surface and became the second human to set foot on the Moon, and the duo began their tasks of investigating how easily a person could operate on the lunar surface. Early on they also unveiled a plaque commemorating their flight, and also planted the flag of the United States. The flag used on this mission had a metal rod to hold it horizontal from its pole. Since the rod did not fully extend, and the flag was tightly folded and packed during the journey, the flag ended up with a slightly wavy appearance, as if there were a breeze.^[87] Shortly after the flag planting, President Richard Nixon spoke to them by a telephone call from his office. The President spoke for about a minute, after which Armstrong responded for about thirty seconds.^[88]

In the entire Apollo 11 photographic record, there are only five images of Armstrong partly shown or reflected. The mission was planned to the minute, with the majority of photographic tasks to be performed by Armstrong with their single Hasselblad camera.^[89]

After helping to set up the Early Apollo Scientific Experiment Package, Armstrong went for a walk to what is now known as East Crater, 65 yards (59 m) east of the LM, the greatest distance traveled from the LM on the mission. Armstrong's final task was to leave a small package of memorial items to deceased Soviet cosmonauts Yuri Gagarin and Vladimir Komarov, and Apollo 1 astronauts Gus Grissom, Ed White and Roger Chaffee. The time spent on EVA during Apollo 11 was about two-and-a-half hours, the shortest of any of the six Apollo lunar landing missions;^[90] each of the subsequent five landings were allotted gradually longer periods for EVA activities – the crew of Apollo 17, by comparison, spent over 22 hours exploring the lunar surface.^[90]

Return to Earth[link]

The Apollo 11 crew and President Richard Nixon

After they re-entered the LM, the hatch was closed and sealed. While preparing for the liftoff from the lunar surface, Armstrong and Aldrin discovered that in their bulky spacesuits, they had broken the ignition switch for the ascent engine; using part of a pen, they pushed the circuit breaker in to activate the launch sequence,^[91] and Aldrin still possesses the pen which they used to do this. The lunar module then continued to its rendezvous and docked with Columbia, the command and service module. The three astronauts returned to Earth and splashed down in the Pacific ocean, to be picked up by the USS Hornet (CV-12).^[92]

After being released from an 18-day quarantine to ensure that they had not picked up any infections or diseases from the Moon, the crew were feted across the United States and around the world as part of a 45-day "Giant Leap" tour. Armstrong then took part in Bob Hope's 1969 USO show, primarily to Vietnam.^[93] In May 1970, Armstrong traveled to the Soviet Union to present a talk at the 13th annual conference of the International Committee on Space Research; after arriving in Leningrad from Poland, he traveled to Moscow where he met Premier Alexei Kosygin. He was the first westerner to see the supersonic Tupolev Tu-144 and was given a tour of the Yuri Gagarin Cosmonauts Training Center, which Armstrong described as "a bit Victorian in nature".^[94] At the end of the day, he was surprised to view delayed video of the launch of Soyuz 9 – it had not occurred to Armstrong that the mission was taking place, even though Valentina Tereshkova had been his host and her husband, Andriyan Nikolayev, was on board.^[95]

Life after Apollo[link]

Teaching[link]

Neil Armstrong Hall of Engineering at Purdue University

Armstrong announced shortly after the Apollo 11 flight that he did not plan to fly in space again.^[96] He was appointed Deputy Associate Administrator for aeronautics for the Office of Advanced Research and Technology (DARPA), but served in this position for only a year, and resigned from it and NASA as a whole in 1971.^[97]

He accepted a teaching position in the Department of Aerospace Engineering at the University of Cincinnati,^[98] having decided on Cincinnati over other universities, including his alma mater, Purdue, because it had a small Aerospace department; he hoped that the faculty members would not be annoyed that he came straight into a professorship with only the USC master's degree.^[99] He began the work while stationed at Edwards years before, and finally completed it after Apollo 11 by presenting a report on various aspects of Apollo, instead of a thesis on simulation of hypersonic flight. The official job title he received at Cincinnati was University Professor of Aerospace Engineering. After teaching for eight years, he resigned in 1979 without explaining his reason of leaving.^[100]

NASA accident investigations[link]

Armstrong served on two spaceflight accident investigations. The first was in 1970, after Apollo 13, where as part of Edgar Cortwright's panel, he produced a detailed chronology of the flight. Armstrong personally opposed the report's recommendation to re-design the service module's oxygen tanks, the source of the explosion.^[101] In 1986 President Ronald Reagan appointed him to the Rogers Commission, which investigated the Space Shuttle Challenger disaster of that year. As vice-chairman, Armstrong was in charge of the operational side of the commission.^[102]