neil armstrong trip to moon

Neil Armstrong: First man on the moon

A brief biography of Neil Armstrong.

Early career and NASA work

Apollo 11 and the first moonwalk, after apollo 11, and armstrong's death, armstrong's legacy, additional resources, bibliography.

Neil Armstrong was a NASA astronaut and aeronautical engineer. He famously became the first person to walk on the moon on July 20, 1969 during Apollo 11 . Armstrong also flew on NASA's Gemini 8 mission in 1966. 

He retired from NASA in 1971 and remained active in the aerospace community, although he chose to keep mostly out of the public spotlight. Armstrong died Aug. 25, 2012, at age 82.

Armstrong was famously reticent about his accomplishments, preferring to focus on the team that helped him get to the moon rather than his own first steps. "I guess we all like to be recognized not for one piece of fireworks, but for the ledger of our daily work," Armstrong said in an interview with CBS's "60 Minutes" program in 2005. 

In another interview, when asked what it feels like to have his footprints remain on the moon's surface for thousands of years, Armstrong said, "I kind of hope that somebody goes up there one of these days and cleans them up," The Independent reported.

Related: Apollo landers, Neil Armstrong’s bootprint and other human artifacts on moon officially protected by new US law

Armstrong was born in Wapakoneta, Ohio, on Aug. 5, 1930, to Stephen Koenig Armstrong and Viola Louise Engel. 

Neil was a naval aviator from 1949 to 1952 and served in the Korean War. He earned his bachelor of science degree in aeronautical engineering from Purdue University in 1955. (Many years later, after he became world-famous, he also received a master of science in aerospace engineering from the University of Southern California in 1970.) 

Armstrong became a test pilot for NASA (then known as NACA, the National Advisory Committee for Aeronautics) and flew the X-15, a rocket-powered, missile-shaped aircraft that tested the limits of high-altitude flight. During his long career as a pilot, Armstrong flew more than 200 different aircraft, from jets to gliders and even helicopters.

In 1962, Armstrong was selected to be part of NASA's second group of astronauts, who flew on the two-seat Gemini missions to test out space technology, and the three-seat Apollo missions that ultimately took 12 people to the surface of the moon. Armstrong's first flight was as command pilot of the Gemini 8 mission in March 1966 — the sixth crewed mission of that series. 

Armstrong and pilot David Scott completed the first orbital docking of two spacecraft, joining their Gemini 8 spacecraft to an uncrewed Agena target vehicle. However, the two-man crew experienced a serious problem when a thruster on the Gemini 8 spacecraft became stuck open. With the astronauts whipping around faster than one revolution per second, Armstrong managed to gain control again by using the re-entry system thrusters. The event was the first serious emergency in space and although the mission ultimately ended safely, the spacecraft was forced to splash down early because the re-entry system was already expended.

Armstrong also narrowly avoided a nasty accident in May 1968, this time within Earth's atmosphere , while flying the Lunar Landing Research Vehicle — a machine that could fly somewhat like a lunar module and simulate landings on the moon. Fuel for the attitude thrusters ran out and Armstrong was forced to eject just seconds before the vehicle crashed, NASA reported . Armstrong escaped unharmed.

The Apollo 11 crew members were announced to the public in January 1969. NASA's chief of the Astronaut Office, Donald Kent "Deke" Slayton, chose an all-veteran team of Neil Armstrong (Gemini 8), Edwin "Buzz" Aldrin (Gemini 12) and Michael Collins (Gemini 10), with Armstrong selected to command the mission. His responsibilities included landing on the moon alongside Aldrin, the pilot of the lunar module Eagle. Collins would remain in lunar orbit aboard the command module Columbia. (Collins was originally supposed to be backup pilot for Apollo 11, but his spot in the flight sequence was moved after required surgery on his back forced him off the prime crew for Apollo 8.)

As the lander approached the moon, Armstrong took over the controls when he saw that the computer was guiding them to a boulder-filled landing zone. At 4:14 p.m. EDT (2014 GMT), Armstrong and Aldrin landed on the moon, with only 25 seconds of fuel left. Armstrong radioed, "Houston, Tranquility Base here. The Eagle has landed." Capsule communicator and astronaut Charles Duke responded from Earth: "Roger … Tranquility, we copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot."

The schedule called for the astronauts to sleep before the first moonwalk, but they elected to go outside early because they felt they would not be able to sleep. In view of a black-and-white television camera transmitting his movements live to Earth, Armstrong descended Eagle's lander and touched his left foot upon the surface at 10:56 p.m. EDT July 20 (0256 GMT July 21). His first words were "That's one small step for a man, one giant leap for mankind." (The "a" was lost to radio static, but later analysis of the sound wave showed that Armstrong did say it.)

Armstrong and Aldrin together explored the surface during a moonwalk that lasted 2 hours and 36 minutes. They collected 48.5 pounds (22 kilograms) of material from the surface — including 50 moon rocks — as well as deploying experiments, planting the U.S. flag and taking a moment to speak with the U.S. president at the time, Richard Nixon. 

The Eagle's crew lifted off safely from the moon on July 21, docked with Columbia, and voyaged back to Earth for a successful ocean landing on July 24. The astronauts went into quarantine to mitigate the (unlikely) risk that they were carrying some sort of moon germs back with them, and then embarked on a world tour to celebrate the mission.

After his time as an astronaut, Armstrong was deputy associate administrator for aeronautics at NASA headquarters . He resigned from NASA in 1971. From 1971 to 1979, he was a professor of aerospace engineering at the University of Cincinnati. Then from 1982 to 1992, Armstrong was chairman of Computing Technologies for Aviation Inc. in Charlottesville, Virginia. Armstrong also participated in the Rogers Commission, which was a presidential commission tasked to look at the causes and events of the fatal Challenger shuttle explosion of Jan. 28, 1986, that killed seven astronauts. 

Armstrong chose to mostly stay out of the spotlight after leaving NASA, although he did reappear periodically for interviews or for anniversary events concerning Apollo 11. Although his public statements were few, he followed spaceflight news and occasionally made public comments on what was happening. He remained a vocal supporter of suborbital spaceflight. On the other hand, the former Apollo astronaut was publicly critical of plans to shift crewed spaceflight from NASA to private spacecraft.

On Aug. 7, 2012 — two days after Armstrong turned 82 years old — the famed moonwalker underwent coronary bypass surgery. Complications from the surgery resulted in his death on Aug. 25. 

"Neil was our loving husband, father, grandfather, brother and friend," his family wrote on the website neilarmstronginfo.com. "For those who may ask what they can do to honor Neil, we have a simple request," they added. "Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink."

Tributes poured in from many public figures, including President Barack Obama, Republican presidential candidate Mitt Romney, then-NASA administrator Charles Bolden, Apollo 11 crewmates Aldrin and Collins, and various space representatives in the public, private and nonprofit spheres. 

"Neil was among the greatest of American heroes — not just of his time, but of all time," Obama's statement read . "When he and his fellow crew members lifted off aboard Apollo 11 in 1969, they carried with them the aspirations of an entire nation. They set out to show the world that the American spirit can see beyond what seems unimaginable — that with enough drive and ingenuity, anything is possible."

A private memorial service for Armstrong was held Aug. 31, 2012, at the Camargo Club in Cincinnati. Two weeks later, a publicly televised memorial service was held at the National Cathedral in Washington, D.C. 

Armstrong was buried at sea Sept. 14, 2012, in a ceremony aboard the guided missile cruiser USS Philippine Sea. Armstrong's family was on board when the ship left port in Mayport, Florida, and they released his ashes somewhere in the Atlantic Ocean. Obama ordered flags around the United States to fly at half-staff on the day of the funeral.

In 2015, the Smithsonian Institution revealed that Armstrong had kept aside a cloth bag full of small parts from the lunar module Eagle, which lay undiscovered for decades until his widow, Carol, found it. While Armstrong made no mention of this bag in decades of interviews, the bag was discussed a few times during the mission. 

It is unknown how Armstrong ultimately gained possession of the bag, but it was common during the Apollo years for astronauts to retain souvenirs of their flights. (A month after Armstrong's death, Obama made legal a bill to allow Mercury, Gemini and Apollo astronauts to retain legal title to these mementos.) Former "Mythbusters" host Adam Savage subsequently created a carry bag based on the design of Armstrong's "purse"; the design was actually used in several Apollo missions before and after Apollo 11. 

On Jul. 21, 2009, Neil Armstrong, Michael Collins, and Buzz Aldrin attended the U.S House of Representatives Committee on Science and Technology tribute to the Apollo 11 Astronauts at the Cannon House Office Building on Capitol Hill. During the ceremony, the committee presented the astronauts with a copy of House Resolution 607 honoring their achievements and announced the passage of legislation awarding them and John Glenn the Congressional Gold Medal. 

In a 2013 BBC documentary, Armstrong's brother, Dean, said that he knew of the famous first words on the moon several months before Apollo 11 touched down. Dean reported that Armstrong passed him a handwritten note as the brothers played a late-night game of Risk, according to British newspaper the Telegraph. However, Dean's remarks contradicted many statements by Armstrong himself, who said that the words didn't come to him until he arrived on the moon. The other Apollo 11 astronauts have also backed up Armstrong's assertions.

In 2017, a rare gold lunar model was stolen from the Armstrong Air and Space Museum in Wapakoneta. "Entry to the museum was discovered and taken was a solid gold replica of the 1969 Lunar Excursion Module that landed on the moon," Russel Hunlock, Wapakoneta police chief, said in a release. "The piece is very rare as it was presented to Neil Armstrong in Paris, France, shortly after the moon landing." 

On Oct. 12, 2018, Universal Pictures released a Neil Armstrong biography based on James R. Hansen's book "First Man: The Life of Neil A. Armstrong." The movie starred Ryan Gosling as Armstrong. The movie was embroiled in political controversy because the filmmakers decided not to include a scene where Armstrong plants an American flag on the moon's surface, despite the fact that Armstrong did so in reality. Sen. Marco Rubio, a Republican from Florida, tweeted, "This is total lunacy. And a disservice at a time when our people need reminders of what we can achieve when we work together." 

At the Venice Film Festival Gosling defended the filmmaker's choice, reported The Telegraph , saying, "I think [the moon landing] was widely regarded in the end as a human achievement [and] that's how we chose to view it." 

On Aug. 11, 2021, NASA dedicated the Ohio test facility to Neil Armstrong . Armstrong had graciously declined the honor when he was originally asked, but on Wednesday (Aug. 11), nine years after Armstrong died and a week after what would have been his 91st birthday, a group of NASA officials and members of Congress gathered at a small dedication ceremony in Sandusky, Ohio. NASA’s Plum Brook Station is now known as The Neil A. Armstrong Test Facility. 

You can explore 50 Neil Armstrong facts with this article from  Facts.net  or read about Armstrong's life and dreams of space travel  in this book  by James R. Hansen. Discover more about Armstrong in  this informative article  published by the Air and Space Museum.

• Sylvia Doughty Fries “ NASA Engineers and the Age of Apollo ”, The NASA History Series. 
• Hansen, James R. “ First Man: The Life of Neil A. Armstrong ”. Simon and Schuster, 2012. 

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Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. She was contributing writer for Space.com for 10 years before joining full-time. Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, flying parabolic, working inside a spacesuit, and participating in a simulated Mars mission. Her latest book, " Why Am I Taller ?", is co-written with astronaut Dave Williams. Elizabeth holds a Ph.D. and M.Sc. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015; her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Mastodon: https://qoto.org/@howellspace

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On July 20, 1969, a human walked on the Moon for the first time.

Relive the full journey to and from the the Moon with the timeline below.

July 16, 1969 13:32:00 UTC (Universal Coordinated Time) 9:32 am ET (Eastern Time)

Liftoff! The Apollo 11 Spacecraft launched from Cape Kennedy.

Over a million spectators, including Vice President Spiro Agnew and former President Lyndon Johnson, have come to watch the lift off. 

Traveling to the Moon

From launch to landing, Armstrong, Aldrin, and Collins were on a three day journey to the Moon. One thing that was not widely publicized during the Apollo program was that the astronauts carried music with them into space. According to most accounts, the astronauts of Gemini and Apollo listened mainly to adult contemporary and country music. 

Neil Armstrong’s musical tastes were a bit more complex than his colleagues. He chose to bring something spacey onboard his space capsule: Theremin music. 

July 20, 1969 17:44 UTC 1:44 pm ET

The lunar module with Armstrong and Aldrin aboard was undocked from the command module. At 101:36 GET, the descent to the surface of the Moon began.

Michael Collins stayed aboard the Command Module Columbia , serving as a communications link and photographing the lunar surface.

More about Collins's journey to the far side of the Moon

July 20, 1969 20:17 UTC 4:17 pm ET

The Eagle Has Landed!

The lunar module touched down on the surface on the Moon.

July 21, 1969 2:51 UTC   July 20, 1969 10:51 pm ET

Neil Armstrong begins his descent from the lunar module and takes humankind’s first steps on the Moon, followed by Buzz Aldrin. 

July 20, 1969 2:56 UTC   July 21, 1969 10:56 pm ET

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

On the Moon, the astronauts carried out a planned series of experiments. Approximately two hours and fifteen minutes later, the astronauts prepared to reenter the lunar module. 

About the Experiments

July 21, 1969 17:54 UTC 1:54 pm ET

The ascent from the lunar surface began. At 21:35 UTC (5:35 pm ET) lunar module would rendezvous with the command and service modules, where Michael Collins would welcome back Aldrin and Armstrong. At 23:41 UTC (9:41 pm ET) Lunar Module  Eagle  was jettisoned into lunar orbit. 

What We Left Behind

July 22, 1969 4:55 UTC 11:55 pm ET

Apollo 11 left lunar orbit to return to Earth.

July 24, 1969 4:51 UTC 12:51 pm ET

Splashdown!

The astronauts returned to Earth. In case the Moon had any traces of biological pathogens, the astronauts had to stay in quarantine for 21 days. 

After 21 Days in Quarantine

The United States celebrated the returning heroes in the time-honored tradition reserved for such occasions: parades. The astronauts were lauded at parades across the nation, from New York, to Chicago, to their hometowns, and eventually partook in a world tour.

More About Welcoming the Astronauts Home

The Family That Knocked on Neil Armstrong's Door

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Apollo 11 Plus 45: How Neil Armstrong Got Ready for the Moon

Forty-five years ago today, Neil Armstrong and his crewmates Buzz Aldrin and Mike Collins sat in quarantine near their Saturn 5 rocket and Apollo spacecraft. They were waiting to be launched in less than 24 hours. Because of his coolness in tight spots, Armstrong had been selected to command what was arguably the 20th century’s most magnificent voyage: making the first landing on a place other than Earth.

I first met the small-town test pilot in 1962, when he was chosen to join NASA's second group of astronauts. I quickly learned he was a private person, never cashing in on his high-profile role. He simply did not consider himself anything special. But those around him did, when they were told that Armstrong was barely 21 years old when combat forced him to eject from his crippled jet fighter over Korea. His colleagues also paid notice a decade later, when he brought his X-15 rocket plane back home safely after what looked like certain failure.

The legend about Neil Armstrong’s coolness was firmly established during his first flight into space in 1966, when he fought a stuck control rocket on his Gemini 8 spacecraft to a standstill. His skill with flight controls cleared the way for him to fly the first emergency return from orbit. Two years later, his colleagues were stunned to see him miraculously eject less than three seconds before his moon-landing trainer, known as the "Flying Bedstead," crashed and burned.

Convinced that Armstrong was the coolest astronaut around, NASA's bosses assigned Neil to land America’s first spacecraft on the moon.

NBC News' Cape Canaveral correspondent, Jay Barbree, provides a day-by-day account of 1969's Apollo 11 moon mission.

IN MY BOOK, "Neil Armstrong: A Life of Flight," we find Armstrong and crew waiting in their prelaunch quarantine — a period of isolation designed to make sure they weren't exposed to some show-stopping germ.

Their bosses strolled in wearing hospital masks, and chief flight director Chris Kraft asked, "Have we missed anything, Neil?"

"Nothing, Chris," Neil assured him. "It's all been done. All that's left is the countdown."

Kraft appreciated the confidence coming from a man who wasn't known as a braggart. If there was anything that hadn't been done, not a member of the launch team could say what it was. Kraft knew the equipment was ready. He knew the ground crews, the flight controllers — yes, the astronauts were ... Apollo 11 was the most ready mission ever. He just wanted to find out whether Neil knew something he didn't.

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Then the Apollo program's manager, George Low, had a question. "When you step off the ladder, have you thought about what you're going to say, Neil?"

Neil took a measured moment. He was being questioned by the big boss, and tact was a must. The truth was, he'd been thinking about what he should say. It was also true he had not made a final decision. Neil had run his thoughts by his brother Dean and a couple of others close to him, and he told Apollo’s manager, "Sure, George, I've been thinking about it."

Neil added a smile and quickly directed the conversation onto another topic. "Please tell all the hands that touched Apollo 11, all who worked those long hours, we appreciate it. This launch belongs to each of them. Tell them they'll be riding with us all the way."

MEANWHILE, A CROWD was gathering on the beaches and roadways, congregating in any place that brought them within eyesight or earshot of America’s spaceport. They discovered that a clear view of Apollo 11's launch pad was at a premium. There wasn't a room for rent in central Florida. It had come down to private families renting sofas, cots, even hammocks to anyone who wanted to be there.

By the time morning came, the crowd had swelled to more than a million. About a thousand police officers, sheriff deputies, state troopers, Coast Guard and marine patrol officers struggled to keep the masses orderly.

For myself, I spent the three days and nights before Apollo 11's launch sleeping, bathing, shaving, changing clothes and eating in NBC News' studios overlooking the launch pad, taking notes on everything that did or did not happen. The setup kept me free from the unrelenting phones. Even then, I was writing Neil’s story.

• Read an Excerpt from 'Neil Armstrong: A Life of Flight'
• Neil Armstrong Book Gets Inside a Moonwalker's Mind
• Flash Interactive: Glory Days on the Final Frontier

This is the first installment of an eight-part series retracing the Apollo 11 mission to the moon, day by day. The account is based on material from Jay Barbree's newly published book, "Neil Armstrong: A Life of Flight." Check back with NBCNews.com on Wednesday for the story of Apollo 11's launch.

Barbree will discuss the Apollo legacy on "Virtually Speaking Science," an hourlong talk show that airs on Blog Talk Radio and in the Exploratorium's Second Life virtual auditorium . The show airs July 21 at 8 p.m. ET.

July 17, 2009

For Neil Armstrong, the First Moon Walker, It Was All about Landing the Eagle

Boulders, a crater, moon dust and an overworked computer all stood in the way of humankind's first lunar touchdown

By Andrew Chaikin

The Apollo 11 Lunar Module  Eagle in orbit.

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Editor's note (7/20/16): Neil Armstrong died on  August 25, 2012  at age 82.

"In my view, the emotional moment was the landing. That was human contact with the moon, the landing…. It was at the time when we landed that we were there, we were in the lunar environment, the lunar gravity. That, in my view, was…the emotional high. And the business of getting down the ladder to me was much less significant." Neil Armstrong's words to me, in a 1988 interview, came as a real surprise. Like most people, I think, I had expected that for Armstrong, the moment when he took humanity's first step onto another world would have been the ultimate high point of his Apollo 11 mission. As one of the 600 million people who witnessed history's first moon walk on live TV and radio, I remembered my own sense of awe seeing Armstrong's "one giant leap for mankind." And so, when I interviewed him as part of my research for my 1994 book, A Man on the Moon: The Voyages of the Apollo Astronauts , one of the questions I most wanted to ask was how he felt, taking that incredible step. What I hadn't fully realized was that for a test pilot like Armstrong, compared with landing on the moon, setting foot on it was no big deal. Of all the challenges Armstrong and his crew faced on Apollo 11, the landing itself was far and away the most difficult. Even if there were no malfunctions or other technical problems—an unlikely scenario—the descent would test the abilities of the entire Apollo team, Mission Control, as much as the astronauts themselves. In just 12 minutes, Armstrong and co-pilot Buzz Aldrin had to bring their lunar module Eagle from a height of 50,000 feet, orbiting at a speed of several thousand miles per hour, down to the surface in what amounted to a controlled fall. With no atmosphere, neither wings nor parachutes would have been useful; the only means of controlling the descent was by varying the thrust of Eagle 's descent rocket. Adjusting the lander's flight path was especially tricky; with the craft balanced on rocket thrust, changing direction required tilting the entire spacecraft slightly to one side. And as Armstrong and Aldrin were all too aware, there was only enough fuel for one landing attempt. No wonder that before he and his crewmates left for the moon, Armstrong privately concluded that they had a 90 percent chance of returning safely to Earth but only a 50–50 chance of pulling off a successful landing. And they almost didn't pull it off. The problems began soon after Armstrong and Aldrin began their descent on July 20, 1969. First it was trouble with communications with Earth. Then, alarm tones in the astronauts' headphones signaled something even more serious: the onboard computer, which was controlling the craft's speed and orientation, was becoming overloaded with tasks. Fortunately, experts in Mission Control soon found a way to work around the problem. But the alarms had diverted Armstrong's attention just at the time when he had planned to be watching for landmarks he'd memorized along Eagle 's descent path, and scouting for a good landing spot. By the time the computer trouble quieted down and Armstrong was able to look out the window again, he discovered he had a new problem: Under the control of the computer, the lander was heading directly for a football stadium–size crater. The surrounding area was strewn with boulders, some of which were as big as cars. For a moment—and only a moment—Armstrong was tempted by the idea of trying to set down just shy of those boulders, which he knew would be of great interest to scientists on Earth. But they were going too fast; there were just too many rocks. Armstrong took over from the computer, steering Eagle over the giant crater and the boulder field, and flew onward, hunting for safer ground. While Aldrin read off data on the craft's diminishing speed and altitude, Armstrong scanned the ground ahead. Everyone, in space and on Earth, was very aware that with each passing moment his fuel supply was dwindling. Finally, Armstrong had found a relatively smooth spot, and with just 100 feet  to go he brought Eagle into a final, vertical descent. Armstrong knew it was crucial to land without any sideways motion, lest they risk tipping over at touchdown. But now came one more problem: The blast of the descent rocket was kicking up moon dust , sending it rushing outward in all directions and wrapping the landscape in a fast-moving haze. Armstrong fixed his gaze on rocks sticking up through the blowing dust; using them as reference points, he guided Eagle slowly downward, about as fast as an elevator. Words of warning came from Earth: just 60 seconds of fuel left before he would have to abort the landing. In the back of his mind, Armstrong knew that once they got below 20 feet or so, even if the engine ran out of fuel, in the weaker lunar gravity they would just fall the rest of the way onto the surface and be okay. Now another call from Earth: 30 seconds of fuel left before a mandatory abort. And then, from Aldrin: "contact light." A blue light on the instrument panel signaled that one of three spindly probes at the end of Eagle 's landing legs had touched the surface. The craft settled onto the Sea of Tranquility so gently that neither man felt the impact. Armstrong shut down the engine—with about 20 seconds' worth of fuel remaining. Then all was still. Seven hours later he would emerge from Eagle, climb down its ladder, and take the momentous step the world was so excited about. But for Armstrong himself, the moment of triumph had already come. He keyed his mike and announced, "Houston, Tranquility Base here. The Eagle has landed."

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Apollo 11 mission overview.

Sarah A. Loff

“The Eagle has landed…”

Mission Objective The primary objective of Apollo 11 was to complete a national goal set by President John F. Kennedy on May 25, 1961: perform a crewed lunar landing and return to Earth.

Additional flight objectives included scientific exploration by the lunar module, or LM, crew; deployment of a television camera to transmit signals to Earth; and deployment of a solar wind composition experiment, seismic experiment package and a Laser Ranging Retroreflector. During the exploration, the two astronauts were to gather samples of lunar-surface materials for return to Earth. They also were to extensively photograph the lunar terrain, the deployed scientific equipment, the LM spacecraft, and each other, both with still and motion picture cameras. This was to be the last Apollo mission to fly a “free-return” trajectory, which would enable a return to Earth with no engine firing, providing a ready abort of the mission at any time prior to lunar orbit insertion.

Mission Highlights

Apollo 11 launched from Cape Kennedy on July 16, 1969, carrying Commander Neil Armstrong, Command Module Pilot Michael Collins and Lunar Module Pilot Edwin “Buzz” Aldrin into an initial Earth-orbit of 114 by 116 miles. An estimated 650 million people watched Armstrong’s televised image and heard his voice describe the event as he took “…one small step for a man, one giant leap for mankind” on July 20, 1969.

Two hours, 44 minutes and one-and-a-half revolutions after launch, the S-IVB stage reignited for a second burn of five minutes, 48 seconds, placing Apollo 11 into a translunar orbit. The command and service module, or CSM, Columbia separated from the stage, which included the spacecraft-lunar module adapter, or SLA, containing the lunar module, or LM, Eagle. After transposition and jettisoning of the SLA panels on the S-IVB stage, the CSM docked with the LM. The S-IVB stage separated and injected into heliocentric orbit four hours, 40 minutes into the flight.

The first color TV transmission to Earth from Apollo 11 occurred during the translunar coast of the CSM/LM. Later, on July 17, a three-second burn of the SPS was made to perform the second of four scheduled midcourse corrections programmed for the flight. The launch had been so successful that the other three were not needed.

On July 18, Armstrong and Aldrin put on their spacesuits and climbed through the docking tunnel from Columbia to Eagle to check out the LM, and to make the second TV transmission.

On July 19, after Apollo 11 had flown behind the moon out of contact with Earth, came the first lunar orbit insertion maneuver. At about 75 hours, 50 minutes into the flight, a retrograde firing of the SPS for 357.5 seconds placed the spacecraft into an initial, elliptical-lunar orbit of 69 by 190 miles. Later, a second burn of the SPS for 17 seconds placed the docked vehicles into a lunar orbit of 62 by 70.5 miles, which was calculated to change the orbit of the CSM piloted by Collins. The change happened because of lunar-gravity perturbations to the nominal 69 miles required for subsequent LM rendezvous and docking after completion of the lunar landing. Before this second SPS firing, another TV transmission was made, this time from the surface of the moon.

On July 20, Armstrong and Aldrin entered the LM again, made a final check, and at 100 hours, 12 minutes into the flight, the Eagle undocked and separated from Columbia for visual inspection. At 101 hours, 36 minutes, when the LM was behind the moon on its 13th orbit, the LM descent engine fired for 30 seconds to provide retrograde thrust and commence descent orbit insertion, changing to an orbit of 9 by 67 miles, on a trajectory that was virtually identical to that flown by Apollo 10. At 102 hours, 33 minutes, after Columbia and Eagle had reappeared from behind the moon and when the LM was about 300 miles uprange, powered descent initiation was performed with the descent engine firing for 756.3 seconds. After eight minutes, the LM was at “high gate” about 26,000 feet above the surface and about five miles from the landing site.

The descent engine continued to provide braking thrust until about 102 hours, 45 minutes into the mission. Partially piloted manually by Armstrong, the Eagle landed in the Sea of Tranquility in Site 2 at 0 degrees, 41 minutes, 15 seconds north latitude and 23 degrees, 26 minutes east longitude. This was about four miles downrange from the predicted touchdown point and occurred almost one-and-a-half minutes earlier than scheduled. It included a powered descent that ran a mere nominal 40 seconds longer than preflight planning due to translation maneuvers to avoid a crater during the final phase of landing. Attached to the descent stage was a commemorative plaque signed by President Richard M. Nixon and the three astronauts.

The flight plan called for the first EVA to begin after a four-hour rest period, but it was advanced to begin as soon as possible. Nonetheless, it was almost four hours later that Armstrong emerged from the Eagle and deployed the TV camera for the transmission of the event to Earth. At about 109 hours, 42 minutes after launch, Armstrong stepped onto the moon. About 20 minutes later, Aldrin followed him. The camera was then positioned on a tripod about 30 feet from the LM. Half an hour later, President Nixon spoke by telephone link with the astronauts.

Commemorative medallions bearing the names of the three Apollo 1 astronauts who lost their lives in a launch pad fire, and two cosmonauts who also died in accidents, were left on the moon’s surface. A one-and-a-half inch silicon disk, containing micro miniaturized goodwill messages from 73 countries, and the names of congressional and NASA leaders, also stayed behind.

During the EVA, in which they both ranged up to 300 feet from the Eagle, Aldrin deployed the Early Apollo Scientific Experiments Package, or EASEP, experiments, and Armstrong and Aldrin gathered and verbally reported on the lunar surface samples. After Aldrin had spent one hour, 33 minutes on the surface, he re-entered the LM, followed 41 minutes later by Armstrong. The entire EVA phase lasted more than two-and-a-half hours, ending at 111 hours, 39 minutes into the mission.

Armstrong and Aldrin spent 21 hours, 36 minutes on the moon’s surface. After a rest period that included seven hours of sleep, the ascent stage engine fired at 124 hours, 22 minutes. It was shut down 435 seconds later when the Eagle reached an initial orbit of 11 by 55 miles above the moon, and when Columbia was on its 25th revolution. As the ascent stage reached apolune at 125 hours, 19 minutes, the reaction control system, or RCS, fired so as to nearly circularize the Eagle orbit at about 56 miles, some 13 miles below and slightly behind Columbia. Subsequent firings of the LM RCS changed the orbit to 57 by 72 miles. Docking with Columbia occurred on the CSM’s 27th revolution at 128 hours, three minutes into the mission. Armstrong and Aldrin returned to the CSM with Collins. Four hours later, the LM jettisoned and remained in lunar orbit.

Trans-Earth injection of the CSM began July 21 as the SPS fired for two-and-a-half minutes when Columbia was behind the moon in its 59th hour of lunar orbit. Following this, the astronauts slept for about 10 hours. An 11.2 second firing of the SPS accomplished the only midcourse correction required on the return flight. The correction was made July 22 at about 150 hours, 30 minutes into the mission. Two more television transmissions were made during the trans-Earth coast.

Re-entry procedures were initiated July 24, 44 hours after leaving lunar orbit. The SM separated from the CM, which was re-oriented to a heat-shield-forward position. Parachute deployment occurred at 195 hours, 13 minutes. After a flight of 195 hours, 18 minutes, 35 seconds – about 36 minutes longer than planned – Apollo 11 splashed down in the Pacific Ocean, 13 miles from the recovery ship USS Hornet. Because of bad weather in the target area, the landing point was changed by about 250 miles. Apollo 11 landed 13 degrees, 19 minutes north latitude and 169 degrees, nine minutes west longitude July 24, 1969.

Crew Neil Armstrong, Commander Edwin E. “Buzz” Aldrin Jr., Lunar Module Pilot Michael Collins, Command Module Pilot

Backup Crew James A. Lovell, Commander Fred W. Haise Jr., Lunar Module Pilot William A. Anders, Command Module Pilot

Payload Columbia (CSM-107) Eagle (LM-5)

Prelaunch Milestones 11/21/68 – LM-5 integrated systems test 12/6/68 – CSM-107 integrated systems test 12/13/68 – LM-5 acceptance test 1/8/69 – LM-5 ascent stage delivered to Kennedy 1/12/69 – LM-5 descent stage delivered to Kennedy 1/18/69 – S-IVB ondock at Kennedy 1/23/69 – CSM ondock at Kennedy 1/29/69 – command and service module mated 2/6/69 – S-II ondock at Kennedy 2/20/69 – S-IC ondock at Kennedy 2/17/69 – combined CSM-107 systems tests 2/27/69 – S-IU ondock at Kennedy 3/24/69 – CSM-107 altitude testing 4/14/69 – rollover of CSM from the Operations and Checkout Building to the Vehicle Assembly Building 4/22/69 – integrated systems test 5/5/69 – CSM electrical mate to Saturn V 5/20/69 – rollout to Launch Pad 39A 6/1/69 – flight readiness test 6/26/69 – Countdown Demonstration Test

Launch July 16, 1969; 9:32 a.m. EDT Launch Pad 39A Saturn-V AS-506 High Bay 1 Mobile Launcher Platform-1 Firing Room 1

Orbit Altitude: 118.65 miles Inclination: 32.521 degrees Orbits: 30 revolutions Duration: eight days, three hours, 18 min, 35 seconds Distance: 953,054 miles Lunar Location: Sea of Tranquility Lunar Coordinates: .71 degrees north, 23.63 degrees east

Landing July 24, 1969; 12:50 p.m. EDT Pacific Ocean Recovery Ship: USS Hornet

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13.7 Cosmos & Culture

Dreams of travel to the moon, and beyond.

Marcelo Gleiser

Neil Armstrong stands next to his X-15 rocket plane at Edwards Air Force Base in California. NASA hide caption

Neil Armstrong stands next to his X-15 rocket plane at Edwards Air Force Base in California.

The recent passing of Neil Armstrong brings back vivid memories of being huddled with my cousins in front of a large b&w TV on July 20, 1969, incredulous eyes popping out of our heads.

The transformative power of this most amazing feat was such that, even in distant Rio de Janeiro to a 10-year-old boy, the image of an American astronaut actually walking on our natural satellite quickly acquired the power of a mythic vision. If Man could do this, if American science could do this, I wanted to do this too.

Given the realities of growing up in Brazil in the 1970s, it was to my imagination that I turned. I proceeded to learn the science of how to go to the moon and, no less importantly, dove into fictional tales of travel to its surface.

As space pioneer Robert H. Goddard said, "It is difficult to say what is impossible, for the dream of yesterday is the hope of today and the reality of tomorrow."

In perhaps no other area is science's debt to fiction as clear as in space exploration.

Looking at some of the first fictional narratives of travel to the moon, one is doubly struck by how freely the imagination runs in the absence of actual data, and by how remarkably difficult it is to transform imagination into reality. To dream of going to the moon and actually landing there are two very different things. Both should be celebrated as complementary aspects of our humanity, as dreamers and as inventors: every invention starts with a dream.

The first fictional tale of a trip to the Moon on record apparently belongs to the Roman rhetorician and satirist Lucian (c. 120 CE), who, in spite of being credited as Roman, was ethnically Assyrian and wrote in Greek. In a feat that inspired many of the first who wrote of imagined trips to other worlds, such as Johannes Kepler, Cyrano de Bergerac, Jonathan Swift and Voltaire, Lucian tells the story of how he, in the company of 50 other sailors, set off to the explore the oceans to see where they ended when:

"a sudden [and] most violent whirlwind arose and carried the ship above three thousand stadia, lifting it up above the water, from whence it did not let us down again into the seas but kept us suspended in mid air. In this manner we hung for seven days and nights, and on the eighth beheld a large tract of land, like an island, round, shining, and remarkably full of light ..." (Note: one stadium equals 607 feet.)

Once on the Moon, the explorers get embroiled in all sorts of adventures, including a war against the kingdom of the sun and its creatures which, in a tradition Lucian links to Homer and the monsters of his Ulysses , tend to be bizarre. War, it seems, is an inescapable condition of human-like creatures, a sort of incurable infirmity. Or, as Lucian wrote, "Well may they say war is the parent of all things."

I wonder what the stoic and quietly heroic Neil Armstrong made of stories such as Lucian's. Although he deemed himself "a white-socks, pocket-protector, nerdy engineer," he also had moments of deep inspiration, as in his statement to a 2001 NASA oral history project:

"Looking back, we were really very privileged to live in that thin slice of history where we changed how man looks at himself, and what he might become, and where he might go."

To this now grown-up boy, Armstrong remains a beacon of light in a world in dire need of such heroes.

You can keep up with more of what Marcelo is thinking on Facebook and Twitter @mgleiser .

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8 Little‑Known Facts About the Moon Landing

By: History.com Editors

Updated: July 17, 2024 | Original: July 20, 2019

It was a feat for the ages. Just seven years before, a young president had challenged the nation to land a man on the moon—not because it was “easy,” as John F. Kennedy said in 1962 , but because it was “hard.” By July 20, 1969, Neil Armstrong backed down a ladder and onto the moon’s surface.

Along the way to achieving JFK's vision, there was plenty of hard work, drama and surprise. Here are some lesser-known moments throughout the epic U.S. effort to reach the moon.

1. Moon dirt smells.

A big question facing the NASA team planning the Apollo 11 moon landing was what would the moon’s surface be like—would the lander’s legs touch down on firm ground, or sink into something soft? The surface turned out to be solid, but the real surprise was that the moon had a smell.

Moon soil is extremely clingy and hard to brush off, so when Armstrong and Aldrin returned to the lunar module and repressurized it, lunar dirt that had clung to the men’s suits entered the cabin and began to emit an odor. The astronauts reported that it had a burned smell like wet fireplace ashes, or like the air after a fireworks show.

Scientists would never get the chance to investigate just what the crew was smelling. While moon soil and rock samples were sent to labs in sealed containers, once they were opened back on Earth, the smell was gone. Somehow, as Charles Fishman, author of One Giant Leap , says, “The smell of the moon remained on the moon.”

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2. JFK was more focused on beating the Soviets than in space.

In public, President John F. Kennedy had boldly pledged that the United States would “set sail on this new sea because there is new knowledge to be gained, and new rights to be won, and they must be won and used for the progress of all people."

But secret tapes of Kennedy’s discussions would later reveal that in private, JFK was less interested in space exploration than in one-upping the Soviets.

In a 1962 meeting with advisors and NASA administrators , JFK confessed, "I'm not that interested in space." But he was interested in winning the Cold War . Just months after JFK’s inauguration, the Soviet Union had sent the first man into space. Kennedy asked his vice president, Lyndon B. Johnson, how the U.S. could score a win against the Soviets.

One of the best ways to show U.S. dominance, Johnson reported back, was by sending a manned mission to the moon. Johnson, in fact, had long been a space advocate, saying in 1958 , "Control of space is control of the world."

3. The Soviets covered up their efforts to get to the moon first.

It turns out that the United States wasn’t alone in wanting to demonstrate its dominance by landing humans on the moon. The Soviet Union was also gunning to accomplish the feat. But once U.S. astronauts got there first, the Soviets tried to keep their efforts on the down-low.

At first, “secrecy was necessary so that no one would overtake us,” wrote journalist Yaroslav Golovanov in the Soviet newspaper, Komsomolskaya Pravda . “But later, when they did overtake us, we had to maintain secrecy so that no one knew that we had been overtaken.”

4. Astronauts trained for microgravity by walking “sideways.”

How do you prepare to send someone to a place no one has ever gone before? For NASA in the 1960s, the answer was to create simulations that mimicked aspects of what astronauts could expect to encounter.

Armstrong and Aldrin rehearsed collecting samples on fake, indoor moonscapes. Armstrong practiced taking off and landing in the Lunar Landing Training Vehicle in Houston. And, to simulate walking in the moon’s lower-gravity atmosphere, astronauts were suspended sideways by straps and then walked along a tilted wall.

NASA and the U.S. Geological Survey even blasted out craters at Cinder Lake, Arizona to create a landscape that matched part of the moon’s surface—because, after all, practice makes perfect.

5. Civil rights activists got a front-row seat to the Apollo 11 launch.

Not everyone was gung-ho about the U.S. effort to land people on the moon. A few days before the scheduled launch of Apollo 11, a group of activists, led by civil rights leader Ralph Abernathy, arrived outside the gates of the Kennedy Space Center. They brought with them two mules and a wooden wagon to illustrate the contrast between the gleaming white Saturn V rocket and families who couldn’t afford food or a decent place to live.

Amid the heady build-up to the launch, the NASA administrator, Thomas Paine, came out to talk to the protestors, face-to-face. After Paine and Abernathy talked for a while under lightly falling rain, Paine said he hoped Abernathy would “hitch his wagons to our rocket, using the space program as a spur to the nation to tackle problems boldly in other areas, and using NASA’s space successes as a yardstick by which progress in other areas should be measured.”

Paine then arranged to have members of the group attend the next day’s launch from a VIP viewing area. Abernathy prayed for the safety of the astronauts and said he was as proud as anyone at the accomplishment.

6. Buzz Aldrin took holy communion on the moon.

When Apollo 11‘s Eagle lunar module landed on the moon on July 20, 1969, astronauts Neil Armstrong and Buzz Aldrin had to wait before venturing outside. Their mission ordered them to take a pause before the big event . 

So Aldrin used some of the time doing something unexpected, something no man had ever attempted before. Alone and overwhelmed by anticipation, he took part in the first Christian sacrament ever performed on the moon—a rite of Christian communion.

7. Scientists were worried about space germs infecting Earth.

After risking their lives for the advancement of humanity, Armstrong, Aldrin and Collins had the dubious pleasure of being stuck in planetary protection quarantine on their return. Since humans had never been to the moon before, NASA scientists couldn’t be sure that some deadly space-borne plague hadn’t hitched a ride on the astronauts.

As soon as their re-entry capsule splashed down in the Pacific Ocean on July 24, the trio was transferred to a mobile quarantine facility inside which they were transported to NASA Lunar Receiving Laboratory at Johnson Space Center where they had access to a larger quarantine facility until their release on August 10, 1969.

8. President Nixon was anxious the mission could fail.

While President Kennedy had rallied the nation to land a man on the moon, he was assassinated before he could see the Apollo mission achieve his vision. That nerve-racking honor fell to President Richard Nixon, who had been elected in 1968.

Watching Neil Armstrong and Buzz Aldrin take their first steps on the moon, Nixon’s anxiety reached a peak. If anything went wrong, he would have to manage America’s outrage over billions of tax dollars culminating in the death of two astronauts. 

His staff had prepared a statement to be read in the event the worst happened and organized a priest to commit their souls to the deep, much like a burial at sea.

Watching Apollo 11 live from the moon, the President could only hope he wouldn't have to read it.

He didn’t. The men who had traveled more than 200,000 miles to the moon and then stepped foot on an alien world had survived. And the United States would go on to complete six crewed missions that landed a total of 12 astronauts on the moon from 1969 to 1972.

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Space radiation: the Apollo crews were extremely lucky

Professor of Space Physics, Lancaster University

Disclosure statement

Jim Wild receives research funding from UK Research and Innovation, specifically the Natural Science Research Council and the Science and Technology Facilities Council.

Lancaster University provides funding as a founding partner of The Conversation UK.

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As the 50th anniversary of humankind’s first moon landing approaches, the conspiracy theories that claim the Apollo missions were a hoax refuse to die. One perennial anomaly pointed to by moon landing deniers is that the Apollo astronauts could never have survived their passage of two belts of intense radiation partly surrounding the Earth at heights of several thousand kilometres.

Although some fairly straightforward physics can dispense with the idea of a barrier of deadly radiation imprisoning us on our planet, like all good conspiracy theories it is built on a kernel of truth. There is potentially harmful radiation in space. So how did the astronauts survive it?

The term “radiation” is used to describe energy that is emitted in the form of electromagnetic waves and/or particles. Humans can perceive some forms of electromagnetic radiation: visible light can be seen and infrared radiation (heat) can be felt.

Meanwhile, other varieties of radiation such as radio waves, X-rays and gamma rays are not visible and require special equipment to be observed. Worryingly, when high energy (ionising) radiation encounters matter, it can cause changes at the atomic level, including in our bodies .

To the moon and beyond is a new podcast series from The Conversation marking the 50th anniversary of the moon landings. Listen and subscribe here .

There are a several sources of ionising radiation in space. The sun continuously pours out electromagnetic radiation across all wavelengths – especially as visible, infrared and ultraviolet radiation. Occasionally, enormous explosions on the solar surface known as solar flares release massive amounts of X-rays and gamma rays into space, as well as energetic electrons and protons (which make up the atomic nucleus along with neutrons). These events can pose a hazard to astronauts and their equipment even at distances as far from the sun as Earth, the moon and Mars.

Potentially dangerous radiation in space also originates from outside our solar system. Galactic cosmic rays are high energy, electrically charged atomic fragments that travel at nearly the speed of light and arrive from all directions in space.

On Earth, we are protected from most of this ionising radiation. The Earth’s strong magnetic field forms the magnetosphere , a protective bubble that diverts most dangerous radiation away, while the Earth’s thick atmosphere absorbs the rest.

But above the atmosphere, the magnetosphere traps energetic subatomic particles in two radiation regions. These “ Van Allen belts ” comprise an inner and outer torus of electrically charged particles.

Lucky escape

So how did NASA solve the problem of crossing the Van Allen belts? The short answer is they didn’t. To get to the moon, a spacecraft needs to be travelling quickly to climb far enough away from the Earth such that it can be captured by the moon’s gravity. The trans-lunar orbit that the Apollo spacecraft followed from the Earth to the moon took them through the inner and outer belts in just a few hours.

Although the aluminium skin of the Apollo spacecraft needed to be thin to be lightweight, it would have offered some protection. Models of the radiation belts developed in the run-up to the Apollo flights indicated that the passage through the radiation belts would not pose a significant threat to astronaut health. And, sure enough, documents from the period show that monitoring badges worn by the crews and analysed after the missions indicated that the astronauts typically received doses roughly less than that received during a standard CT scan of your chest.

But that is not the end of the story. To get to the moon and safely back home, the Apollo astronauts not only had to cross the Van Allen belts, but also the quarter of a million miles between the Earth and the moon – a flight that typically took around three days each way.

They also needed to operate safely while in orbit around the moon and on the lunar surface. During the Apollo missions, the spacecraft were outside the Earth’s protective magnetosphere for most of their flight. As such, they and their crews were vulnerable to unpredictable solar flares and events and the steady flux of galactic cosmic rays.

The crewed Apollo flights actually coincided with the height of a solar cycle , the periodic waxing and waning of activity that occurs every 11 years. Given that solar flares and solar energetic particle events are more common during times of heightened solar activity, this might seem like a cavalier approach to astronaut safety.

There is no doubt that the political imperative in the 1960s to put US astronauts on the moon “in this decade” was the primary driving factor in the mission timing, but there are counterintuitive benefits to spaceflight during solar activity maxima. The increased strength of the sun’s magnetic field that permeates the solar system acts like an umbrella – shielding the Earth, moon and planets from galactic cosmic rays and therefore lessening the impact on astronaut radiation doses.

MORE ON THE MOON AND BEYOND Join us as we delve into the last 50 years of space exploration and the 50 years to come. From Neil Armstrong’s historic first step onto the lunar surface to present-day plans to use the moon as a launchpad to Mars, hear from academic experts who’ve dedicated their lives to studying the wonders of space.

History tells us that the gamble of flying during the years of high solar activity during the Apollo era paid off. None of the Apollo flights were blasted by powerful solar flares or engulfed by clouds of solar energetic particles. But there could have been a different outcome.

On August 4, 1972 – mid-way between the safe return to Earth of the Apollo 16 crew and the launch of Apollo 17 – a solar energetic particle event was detected. Had this struck a crew en route to the moon, or working on the lunar surface, it is likely that the astronauts would have needed to make an emergency return to Earth for prompt and potentially life-saving medical treatment, all while suffering from acute radiation sickness.

Even now, forecasting “space weather” is a challenge. Astronauts working on board the International Space Station in low Earth orbit benefit from much of the protection offered by the Earth’s magnetosphere, but they can also take shelter in the best shielded areas of the station if required.

But for crews on future lunar missions, or beyond the moon to Mars, dealing with the space radiation risk remains a key challenge . When your flight lasts months rather than days, the odds of dodging space radiation bullets are simply not as favourable.

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