Apollo 11

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Apollo 11
Mission Insignia
Mission Statistics
Mission name: Apollo 11
Call sign: Command module:
Lunar module:
Number of
Launch: July 16, 1969
13:32:00 UTC
Kennedy Space Center, Florida
LC 39A
July 20, 1969
20:17:40 UTC
Sea of Tranquility
0° 40' 26.69" N,
23° 28' 22.69" E [1]
(based on the IAU
Mean Earth Polar Axis
coordinate system)
Lunar EVA
2 h 31 min 40 s
Lunar surface
21 h 36 min 20 s
Lunar sample
21.55 kg (47.5 lb)
Splashdown: July 24, 1969
16:50:35 UTC
Template:Coor dm
Time in
lunar orbit:
59 h 30 min 25.79 s
Mass: (see mission
Crew Picture

L-R: Armstrong, Collins, and Aldrin
Apollo 11 Crew

The Apollo 11 mission was the first manned lunar landing. It was the fifth manned mission in the Apollo program.

File:First step on moon.jpg
Neil Armstrong takes first step onto the Moon

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


Backup crew

Support crew

Mission highlights

The first Apollo landing site, in the southern Sea of Tranquility about 20 km (12 mi) southwest of the crater Sabine D, was selected in part because it had been characterized as relatively flat and smooth by the automated Ranger 8 and Surveyor 5 landers, as well as by Lunar Orbiter mapping spacecraft, and therefore unlikely to present major landing or Extra-vehicular activity (EVA) challenges. Armstrong bestowed the name "Tranquillity Base" on the landing site immediately after touchdown.

The Apollo 11 mission launched from the Kennedy Space Center on July 16, 1969. After one and a half Earth orbits the command/service module separated from the last remaining Saturn V stage, turned around, and docked its nose to the top of the lunar module still nestled in the Lunar Module Adaptor.

File:Apollo 11 bootprint.jpg
Buzz Aldrin bootprint. It was part of an experiment to test the properties of the lunar regolith

On July 20, 1969, while on the far side of the Moon, the lunar module, called Eagle, separated from the Command Module, named Columbia. Collins, now alone aboard Columbia, carefully inspected Eagle as it pirouetted before him. Soon after, Armstrong and Aldrin fired Eagle's engine and began their descent. They soon saw that they were "running long"; Eagle was 4 seconds further along its descent trajectory than planned, and would land miles west of the intended site. The LM navigation and guidance computer reported several "program alarms" as it guided the LM's descent. These alarms tore the crew's attention away from the scene outside as the descent proceeded. In NASA's Mission Control Center in Houston, Texas, a young controller named Steve Bales was able to tell the flight director that it was safe to continue the descent in spite of the alarms. Once they were able to return their attention to the view outside, the astronauts saw that their computer was guiding them toward a landing site full of large rocks scattered around a large crater. Armstrong took manual control of the lunar module at that point, and guided it to a landing at 4:17 p.m. Eastern Daylight Time on July 20 with less than 30 seconds' worth of fuel left. Although it is commonly said that the first words spoken on the Moon were Armstrong's announcement that "Houston, Tranquility Base here. The Eagle has landed", they were in fact "Contact Light" said, by Aldrin as the landing probes on the Lunar Module's feet touched the surface.

File:Aldrin Apollo 11.jpg
Buzz Aldrin poses on the Moon allowing Neil Armstrong to photograph both of them using the visor's reflection.

The program alarms were "executive overflows", indicating that the computer could not finish its work in the time allotted. The cause was later determined to be that the LM rendezvous radar was left on during the descent, causing the computer to spend unplanned time servicing the unused radar. Steve Bales received a Medal of Freedom for his "go" call under pressure.

At 2:56 UTC on July 21 (22:56 EDT July 20), six and a half hours after landing, Armstrong made his descent to the Moon surface and took his famous "one giant leap for mankind." Aldrin joined him, and the two spent two-and-a-half hours drilling core samples, photographing what they saw and collecting rocks.


They planned placement of the Early Apollo Scientific Experiment Package (EASEP) and the U.S. flag by studying their landing site through Eagle's twin triangular windows, which gave them a 60° field of view. Preparation required longer than the two hours scheduled. Armstrong had some initial difficulties squeezing through the hatch with his PLSS. According to veteran moonwalker John Young, a redesign of the LM to incorporate a smaller hatch was not followed by a redesign of the PLSS backpack, so some of the highest heart rates recorded from Apollo astronauts occurred during LM egress and ingress.

The Saturn V carrying Apollo 11 took several seconds to clear the tower on July 16, 1969.

The Remote Control Unit controls on Armstrong's chest prevented him from seeing his feet. While climbing down the nine-rung ladder, Armstrong pulled a D-ring to deploy the Modular Equipment Stowage Assembly (MESA) folded against Eagle's side and activate the TV camera. The first images used a Slow-scan television system and were picked up at Goldstone in the USA but with better fidelity by Honeysuckle Creek in Australia. Minutes later the TV was switched to normal television, and the feed was switched to the more sensitive radio telescope station at the Parkes Observatory in Australia. Despite some technical and weather difficulties, ghostly black and white images of the first lunar EVA were received and were immediately broadcast to at least 600 million people on Earth.

After describing the surface ("very fine grained... almost like a powder"), Armstrong stepped off Eagle's footpad and into history as the first human to set foot on another world. He reported that moving in the Moon's gravity, one-sixth of Earth's, was "perhaps even easier than the simulations."

In addition to fulfilling President John F. Kennedy's mandate to land a man on the Moon before the end of the 1960s, Apollo 11 was an engineering test of the Apollo system; therefore, Armstrong snapped photos of the LM so engineers would be able to judge its post-landing condition. He then collected a contingency soil sample using a sample bag on a stick. He folded the bag and tucked it into a pocket on his right thigh. He removed the TV camera from the MESA, made a panoramic sweep, and mounted it on a tripod 12 m (40 ft) from the LM. The TV camera cable remained partly coiled and presented a tripping hazard throughout the EVA.

Aldrin joined him on the surface and tested methods for moving around, including two-footed kangaroo hops. The PLSS backpack created a tendency to tip backwards, but neither astronaut had serious problems maintaining balance. Loping became the preferred method of movement. The astronauts reported that they needed to plan their movements six or seven steps ahead. The fine soil was quite slippery. Aldrin remarked that moving from sunlight into Eagle's shadow produced no temperature change inside the suit, though the helmet was warmer in sunlight, so he felt cooler in shadow.

File:Apollo 11 launch.jpg
A visible shockwave formed as the Saturn V encountered Maximum Dynamic Pressure (Max Q) at about 1 minute 20 seconds into the flight (altitude 12.5 km, 4 km downrange, velocity 1,600 km/h).

Together the astronauts planted the U.S. flag - the ground was too hard to permit them to insert the pole more than about 20 cm (8 in) - then took a phone call from President Richard Nixon.

The MESA failed to provide a stable work platform and was in shadow, slowing work somewhat. As they worked, the moonwalkers kicked up gray dust which soiled the outer part of their suits, the integrated thermal meteoroid garment.

They deployed the EASEP, which included a passive seismograph and a laser ranging retroreflector. Then Armstrong loped about 120 m (400 ft) from the LM to snap photos at the rim of East Crater while Aldrin collected two core tubes. He used the geological hammer to pound in the tubes - the only time the hammer was used on Apollo 11. The astronauts then collected rock samples using scoops and tongs on extension handles. Many of the surface activities took longer than expected, so they had to stop documented sample collection halfway through the allotted 34 min.

During this period Mission Control used a coded phrase to warn Armstrong that his metabolic rates were high and that he should slow down. He was moving rapidly from task to task as time ran out. Rates remained generally lower than expected for both astronauts throughout the walk, however, so Mission Control granted the astronauts a 15 minute extension.

Neil Armstrong works at the LM in one of the few photos taken of him from the lunar surface. NASA photo as11-40-5886

Aldrin entered Eagle first. With some difficulty the astronauts lifted film and two sample boxes containing more than 22 kg (48 lb) of lunar surface material to the LM hatch using a flat cable pulley device called the Lunar Equipment Conveyor. Armstrong then jumped to the ladder's third rung and climbed into the LM.

After transferring to LM life support, the explorers lightened the ascent stage for return to lunar orbit by tossing out their PLSS backpacks, lunar overshoes, one Hasselblad camera, and other equipment. Then they lifted off in Eagle's ascent stage to rejoin CMP Michael Collins aboard Columbia in lunar orbit. Eagle was jettisoned and left in lunar orbit. Later NASA reports mentioned that Eagle's orbit had decayed resulting in it impacting in an "uncertain location" on the lunar surface.

Photo of the actual plaque left on the moon (attached to the ladder of the LM Descent Stage).

After more than 2½ hours on the lunar surface, they returned to Collins on board Columbia, bringing 20.87 kilograms of lunar samples with them. The two Moon-walkers had left behind scientific instruments such as a retroreflector array used for the Lunar Laser Ranging Experiment. They also left an American flag and other mementos, including a plaque (mounted on the LM Descent Stage ladder) bearing two drawings of Earth (of the Western and Eastern Hemispheres), an inscription, and signatures of the astronauts and Richard Nixon. The inscription read:

Here Men From Planet Earth
First Set Foot Upon the Moon
July 1969 A.D.
We Came in Peace For All Mankind.
File:Apollo 11 crew in quarantine.jpg
The crew of Apollo 11 in quarantine after returing to earth, visited by Richard Nixon.

The astronauts returned to earth on July 24, welcomed as heroes. The splashdown point was Template:Coor dm, 2,660 km (1,440 nm) east of Wake Island, or 380 km (210 nm) south of Johnston Atoll, and 24 km (15 mi) from the recovery ship, USS Hornet.

The command module is displayed at the National Air and Space Museum, Washington, D.C.

Contingency television address

The National Archives in Washington, D.C. has a copy of the following contingency memo titled "In Event of Moon Disaster" and dated July 18, 1969, which was prepared by William Safire for President Nixon to read on television, in the event the Apollo 11 astronauts were stranded on the Moon.

"Fate has ordained that the men who went to the Moon to explore in peace will stay on the Moon to rest in peace. These brave men, Neil Armstrong and Edwin Aldrin, know that there is no hope for their recovery. But they also know that there is hope for mankind in their sacrifice.
These two men are laying down their lives in mankind's most noble goal: the search for truth and understanding. They will be mourned by their families and friends; they will be mourned by their nation; they will be mourned by the people of the world; they will be mourned by a Mother Earth that dared send two of her sons into the unknown.
In their exploration, they stirred the people of the world to feel as one; in their sacrifice, they bind more tightly the brotherhood of man. In ancient days, men looked at stars and saw their heroes in the constellations. In modern times, we do much the same, but our heroes are epic men of flesh and blood.
Others will follow, and surely find their way home. Man's search will not be denied. But these men were the first, and they will remain the foremost in our hearts.
File:Armstrong 16mm.jpg
Armstrong on lunar surface with gold visor raised. From 16 mm film (NASA).
For every human being who looks up at the Moon in the nights to come will know that there is some corner of another world that is forever mankind."

The last line of the statement is reminiscent of a Rupert Brooke poem called "The Soldier". The poem starts:

If I should die, think only this of me:
That there's some corner of a foreign field
That is forever England.

Following this address, radio communications with the moon would have been cut off, the astronauts left alone to die, while a clergyman was to commend their souls to "the deepest of the deep" in the fashion of a burial at sea.

Mission trivia and urban legends


  • Some internal NASA planning documents referred to the callsigns of the CSM and LM as "Snowcone" and "Haystack"; these were quietly changed before being announced to the press.
  • Shortly after landing, before preparations have begun for the EVA, Aldrin broadcast that -
This is the LM pilot. I'd like to take this opportunity to ask every person listening in, whoever and wherever they may be, to pause for a moment and contemplate the events of the past few hours and to give thanks in his or her own way.
He then took Holy Communion, privately. At this time, NASA was still fighting a lawsuit brought by Madalyn Murray O'Hair, who had objected to the Apollo 8 crew reading from the Book of Genesis, which demanded that their astronauts refrain from religious activities while in space. As such, Aldrin (an Episcopalian) chose to refrain from directly mentioning this. He had kept the plan quiet, not even mentioning it to his wife, and did not reveal it publicly for several years.
  • Several books indicate that early mission timelines had Buzz Aldrin, not Neil Armstrong, as the first man on the Moon. These books also indicate that Aldrin actively campaigned to be first out. However, the LM egress hatch, when opened, partially blocked the LM Pilot's way. This dictated that the Commander, rather than the LMP, would be the first to exit the LM and descend to the surface.
  • A replica of the footprint left by Neil Armstrong is located in Tranquility Park in Houston, Texas; the park was dedicated in 1979, a decade after the first moon landing.
  • The Australian movie, The Dish (2000), tells the (slightly fictionalised) story of how the images of the moon-walk were received by the radio telescope at Parkes, New South Wales.
  • According to the HBO mini-series From the Earth to the Moon, Michael Collins made the following suggestion as to what Armstrong should say upon stepping onto the lunar surface: "If you had any balls, you'd say 'Oh, my God, what is that thing?' then scream and cut your mic."


  • At some point while on the moon Armstrong supposedly said "Good luck Mr. Gorski". Some years later Gorski died, so he felt he could now explain this remark. As a boy, he heard a couple next door arguing, and the wife said: "Oral sex? Is it oral sex you want? You'll get oral sex when the kid next door walks on the moon, Mr. Gorski!" This story is untrue. [2]
  • Neil Armstrong apparently took tartan where no tartan had been worn before. A tiny swatch of the Clan Armstrong plaid was affixed to his suit when he walked on the Moon. Another item that Armstrong took with him was a special diamond-studded astronaut pin which was given to Deke Slayton by the widows of the Apollo 1 crew. The pin had been intended to be flown in Apollo 1, then given to Deke after the mission, but due to the disaster, the widows ended up giving the pin to him after the funerals. Deke gave the pin to Neil to leave at Tranquillity Base.
  • Two main conspiracy theories surround the mission.
    • Firstly that the landing was a hoax. This is generally discounted, although it has slowly grown in popularity, particularly since the release of the movie Capricorn One (1978), which portrays a NASA attempt to fake a landing on Mars.
    • Secondly, a less well known urban legend suggests that they were being 'watched' while on the Moon, and had seen alien vehicles there. This grew in popularity after the book Someone else is on our Moon was published.
  • According to another legend, a survey undertaken in the 1980s in Morocco revealed that a substantial percentage didn't think man had landed on the Moon. Not because of any hoax theory, but because they simply hadn't heard!

See also

External links


Template:Project Apollo

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