Mark Armstrong and Rick Armstrong said that First Man was the most accurate portrayal of their father Neil Armstrong and their mother Janet Armstrong.

In the breakfast scene just before Apollo 11 launched, NASA sketch artist Paul Calle was played by his own son Chris Calle.

Apollo astronauts were considered government employees, with most at the rank of captain. Regardless of their substantial education, the average yearly income of these astronauts in the 1960s was $17,000 (~$112,000 in 2019 money) solely based on military rank. They also were not paid any hazard pay. Additionally the astronauts were paid per-diem of $8 extra a day (~$56 in 2019 money) for each day they spent in the spacecraft. However their per-diem was "pre-deduction", and they were deducted for living expenses when aboard the spacecraft, as food and a bed was provided for them.

The "1201" and "1202" alarms that sounded during the lunar descent was an indication that the computer was receiving more data than it could process. The procedure to fix this was to cycle the switch, which essentially ended the bottleneck. This was not the last time this error had been encountered in an Apollo flight. When Apollo XII was struck by lightning during its launch, it also triggered a 1202.

On July 16th, 2019, which was the fiftieth anniversary of the Apollo 11 launch, CBS rebroadcast the entire original four-hour news broadcast of Walter Cronkite as he covered the launch in real time. Running from 6:00 a.m. to 10:00 a.m. (CDT), the timing of the rebroadcast was accurate down to the second, and included all the television commercials as well (for sponsors Western Electric, Kellogg's Corn Flakes, and Maxim freeze-dried coffee), which were very few in number. As described by Walter Cronkite some twenty minutes after the launch, during the last few seconds of ignition every news teletype machine from AP, UPI, Reuters, and other non-Soviet news agencies fell completely silent, as the operators had paused to watch the launch on television. For the most part, the world fell silent for the first time in its history because of a single event. He also reported that Soviet television did not cover the launch and it did not receive detailed coverage by the Soviet press.

Common errors were avoided in this film: Earth and the moon are always lit by the sun at the same angle, no clouds appear at high altitudes, the paradoxical nature of accelerating and braking rockets in orbit, no obtrusive lights hidden inside astronaut helmets to show their faces, and no ambient sound in the vacuum of space.

Actor Ryan Gosling first discovered Neil Armstrong's love of the theremin during his background research with Armstrong's family and friends. He brought it to Damien Chazelle and Justin Hurwitz's attention, who later chose to include the strange instrument in the score.

Apollo 11 was not the first Apollo flight to be capable of landing on the moon. Apollo 10, which is referred to in this film, performed a dress rehearsal, with the LEM dropping to an altitude of only 8.4 nautical miles above the lunar surface. If, against mission directives, they had mutinied and carried out the landing, it would not have been an eagle that landed on the moon but a beagle, as the Apollo 10 LEM had been given the name of Peanuts character Snoopy. In May of 2019 astronomers spotted "Snoopy", which has remained in solar orbit since May of 1969.

Buzz Aldrin mentions his Personal Preference Kit (PPK), which was a small pouch in which the astronauts could choose to carry personal items along on the trip. Along with other items, Buzz Aldrin included a small silver cup, a communion wafer, and a small container of communion wine, which he used for a formal personal ceremony when on the moon.

A prominent character in this film is Donald K. Slayton aka Deke Slayton. He was one of the original Mercury astronauts but was grounded due to heart palpitations. Choosing to stay with NASA, he became its first Chief of the Astronaut Office and the Director of Flight Crew Operations. His persistence would eventually pay off, as he was declared healthy in 1971 and finally went into space in the joint American/Soviet Apollo Soyuz flight in 1975, some 14 years after the first manned Mercury mission.

Director Damien Chazelle was particularly concerned with making his film as authentic as possible. This care for detail was maintained until it came to the reproduction of the space capsules. He and chief designer Nathan Crowley agreed that no ship would be enlarged by more than ten percent, even if it sacrificed the comfort of the actors. This also caused complications for framing. The solution was to create a decor that fit in several detachable parts. In fact, the technicians had to break the seats in two to be able to integrate the cameras with the capsule.

The filmmakers used the original blueprints of Neil Armstrong's house to replicate the look of his house in the film.

The Adler Planetarium in Chicago gifted Ryan Gosling certificates for two stars named after his daughters in the constellations of their birth signs, as a thank you for his work on the film.

The original music composed by Justin Hurwitz featured various instruments, including theremin (which Hurwitz learned to play; his performance is in the final score) and a Moog synthesizer, along with an Echoplex tape-based delay unit, which give the score its uniqueness. The Echoplex, which features a sliding playback head that can shift the delay (echo) of the signal sent to the recording head, is used to create single or multiple repeats from information temporarily recorded on a tape loop, which was used for a number of pop recordings in the seventies. Hurwitz also rerecorded a string orchestra being played back through a Leslie rotor cabinet to create special sound effects.

William Safire, one of Nixon's presidential speechwriters, had prepared a statement to be delivered by the president in the event the Apollo 11 mission had failed. NASA White House Liason, astronaut Frank Borman, suggested to Safire that the president should be prepared to address a catastrophic mishap with the mission. Since the most dangerous parts of the mission were the landing and take-off, a mishap most likely meant the astronauts would either crash on the moon or be unable to depart; in either case left stranded there. Safire wrote a short speech titled "In the event of moon disaster" for such a contingency, but did not deliver it to Nixon. After the success of the mission, Safire quietly entered the speech into the presidential records where it remained until it was de-classified and released to the public in 1999. The first line of the speech reads: "Fate has ordained that the men who went to the moon to explore in peace will stay on the moon to rest in peace."

When Neil talks about taking his daughter to Saskatchewan to try to have her treated by the man who developed the technology, he is referring to Dr. Harold E. Johns, who developed Cobalt-60 radiation treatments at the University of Saskatchewan in Saskatoon, Saskatchewan, Canada.

Damien Chazelle's first choice to play the role of Neil Armstrong was Ryan Gosling. Gosling was even rumored to be attached to the project during its development stage, but nothing was officially confirmed. It was not until after Gosling did La La Land (2016) with Chazelle that Gosling would officially sign on to do the project.

To prepare for his role, Ryan Gosling unearthed Lunar Rhapsody, a piece for theremin that Neil Armstrong loved and listened to during the Apollo 11 mission, as well as Egelloc, a musical he had written while at college.

James R. Hansen, biographer of Neil Armstrong, co-produced the film. It is thanks to him that the project was able to succeed. Indeed, the astronaut had full confidence in the writer, who became his friend over the years. "For Neil, as long as you followed Jim's path, there was no problem in making this movie," said producer Wyck Godfrey, who had the chance to meet Armstrong before his death on August 25, 2012. After his death, it was essential to have the support of his family. His sons met screenwriter Josh Singer and director Damien Chazelle and were convinced by their concern for accuracy and authenticity.

After separation from the Agena there is a report of a rate approaching 270. This refers to how many degrees they were tumbling per second, which at 270º meant three quarters of a revolution per second. Their tumble peaked at 296º at which time Armstrong fired a burst from the descent retros and managed to get things under control. Aside from other things, mission rules dictated an abort if the retros were used. After one more orbit, Gemini 8 landed near Japan with astronauts and spacecraft intact. It was later determined that built-up static caused maneuvering rocket number 8 to fire even when turned off. As a result, McDonell Douglas changed their procedures and NASA implemented new emergency procedures. It should be noted that the rate of spin depicted in the film was exaggerated. As for the Agena (designated "GATV-5003"), it was in good shape and NASA was able to control it from the ground. During the Gemini X mission, Armstrong's future Apollo II crewmate Michael Collins retrieved the Agena's meteorite collection tray. NASA continued performing many test procedures and maneuvers with the Agena until its fuel and batteries eventually ran out.

James R. Hansen, the author of First Man: The Life of Neil Armstrong (Simon and Schuster, 2005, 2012), is a two-time nominee for the Pulitzer Prize in History. His 1995 book Spaceflight Revolution: NASA Langley Research Center from Sputnik to Apollo was nominated for the Pulitzer by the National Aeronautics and Space Administration, the only time NASA ever nominated a book for the prize.

The film is based on James R. Hansen's book "The First Man: Discovering Neil Armstrong" (Robert Laffont Editions). After writing a thesis in the history of science and technology at the University of Ohio and spending more than twenty years writing and teaching on the themes of history and space, Hansen decided to start writing his first biography. In 2000, he contacted Neil Armstrong who, reluctant to give interviews, declined the proposal. In the end, it took Hansen two years to convince Armstrong, with the support of his family.

Although it is not shown in the film, the spacecraft was set to slowly rotate as it traveled. This is because the difference between sun and shade in space at this distance ranges from 260º F (127º C) to -280º F (-173º C) and it was necessary that the spacecraft maintain as even an exterior temperature as was practical.

The opening scene shows Armstrong's infamous mishap when flying the X-15 supersonic vehicle, but merges this with a later incident involving Chuck Yeager for economy. Armstrong was flying in a T-33 with Yeager, testing X-15 landing sites when the T-33 became stuck on one lake bed, stranding Armstrong and Yeager in the desert. These early incidents in Armstrong's career became part of the test pilot lore, although Yeager supposedly found the T-33 fiasco hilarious and enjoyed ribbing the younger pilot about it.

Clint Eastwood was originally going to direct the movie.

While Neil Armstrong was the LEM "commander" and Buzz Aldrin the "pilot," Armstrong was the one at the controls of the LEM. Aldrin's designation as pilot meant that he was in charge of monitoring the systems and passing along information to Armstrong, much as how a pilot at an ocean harbor guides the captain of a ship to maneuver the ship into port.

During the Apollo 11 Eagle landing sequence, the actual historic recordings of CAPCOM Charles Duke (Charles "Charlie" Duke) were used for the communications audio from Mission Control.

Damien Chazelle was approached to stage the film once Whiplash (2014) completed, while he had not yet realized La La Land (2016). The director wanted to approach this story as a thriller and make the public feel the dangers faced by the astronaut team.

The film was shipped to cinemas under the pseudonym "Sputnik."

Not content with training them at NASA, Damien Chazelle sent each of his actors YouTube videos of the person they embodied so they could learn to reproduce their phrasing and tics of language. In addition, the director provided a list of books and films to consult. Literary suggestions include titles such as 'Carrying the Fire' by Michael Collins, 'Deke!' by Deke Slayton and Michael Cassutt, and 'First Man' by James R. Hansen. On the movie side, there's For All Mankind (1989), Moonwalk One (1972) and Mission Control: The Unsung Heroes of Apollo (2017).

Ryan Gosling and director Damien Chazelle visited the Armstrong Air and Space museum in Neil Armstrong's hometown of Wapakoneta, Ohio to do research on Armstrong and the Gemini VIII mission.

The Apollo 11 crew eat steak and eggs before their launch. This has been the traditional launch day breakfast of NASA astronauts since 1961, when it was served to Alan Shepard for the first Project Mercury flight.

This was the first Universal Pictures film to use IMAX cameras.

All of the residential scenes were filmed in the "Saddle Creek" neighborhood in Roswell, Georgia in the United States. Neil Armstrong's house was built on a vacant lot in the subdivision, which was surrounded by 1960s/1970s-era homes.

During the final moments of the landing, the controllers were afraid that they would have to abort at the last instant, as the altitude was apparently too high and there did not appear to be enough fuel for a safe landing. This was because Armstrong had to fly over a boulder field and then over a crater. When they passed over the crater, which was deeper than the actual surface suddenly the ground radar jumped to show the desired low altitude, which was within mission limits, making the landing possible.

Sandgren and Chazelle used 16mm film for scenes on land and 35mm for scenes in space to create a feeling that you are really watching this movie in 1969

During the re-entry of Apollo 10, Walter Cronkite can be heard (in the actual broadcast tape) referring to its astronauts as "sailors of the sky" who "slipped the surly bonds of earth." The latter line is from the sonnet "High Flight" by John Gillespie Magee and was written during World War II. The line become world famous when President Ronald Reagan used it in his eulogy of the astronauts killed in the 1986 explosion of the space shuttle Challenger.

The film revived international interest in Neil Armstrong's first wife Janet Armstrong, who plays a central part in the film. She died a few months before the film's release.

The song "Whitey on the Moon" during the protest sequence is a cover of the famous song by singer/poet Gil Scott-Heron. It stands as a critique of the economic priorities of the Space Race for many of the economically and social disenfranchised at the time.

Pablo Schreiber played Jim Lovell, another pilot of the Gemini program and Apollo programs, a character that audiences had already met in Apollo 13 (1995), as portrayed by Tom Hanks.

This was the first film directed by Damien Chazelle where he did not write the script.

The lunar sequence was shot on 70mm IMAX cameras and would have expanded aspect ratio during select sequences exclusively in IMAX theaters before Universal decided not to make any 70mm IMAX prints for distribution.

At 2:10:51 the image with the quote "In the beginning God..." is the actual design of a 6 cent postage stamp issued by the US Postal Service to honor Apollo 8.

The tumble rate of the Gemini capsule, while extreme, never exceeded 296º per second. For dramatic purposes, the visuals in the film depict a rate of more than 500º, which would have resulted in the astronauts blacking out with loss of spacecraft and crew.

Segments from the last voice transmission from the space shuttle Challenger, sent just before it exploded during launch in 1986, were used in one of the trailers.

Alan Bean was the fourth man to walk on the moon and a technical advisor for this movie. He sadly died of a brief illness just after production had finished and before the movie was released.

The intermittent beeps heard during dialogue between Houston and the various spacecraft are known as "Quindar tones". They are remote control trigger tones which trigger the ground transmitters to send voice signal transmissions from CapCom at Mission Control Center to the spacecraft. When CapCom (the communications officer on the ground who speaks to the spacecraft, and who was always a fellow astronaut) presses his PTT (push-to-talk) button, it triggers a Quindar tone which signals the ground transmitters to broadcast the transmissions into space. When the CapCom presses his PTT button to start a transmission, an intro tone (a 2.525KHz sine wave with a length of 250ms) is generated and triggers the ground station transmitters to send. When he is finished talking and releases the button again, a slightly lower outro tone (a 2.475KHz sine wave, also 250ms) is generated to trigger the ground station transmitters to turn off.

The movie included an excerpt of an educational film about the planned lunar mission, as well as an end credit screen saying, "A Presentation of the National Aeronautics and Space Administration: Pelican Films Inc. HQ88."

American flag controversy: On August 31, 2018, it was reported that the film would not include a scene of Armstrong and Aldrin planting the American flag on the Moon. Florida Senator Marco Rubio described the omission as "total lunacy". Damien Chazelle responded with a statement, saying: "I show the American flag standing on the lunar surface, but the flag being physically planted into the surface is one of several moments (...) that I chose not to focus upon. To address the question of whether this was a political statement, the answer is 'no.' My goal with this movie was to share with audiences the unseen, unknown aspects of America's mission to the Moon." Following the film's below-expectations opening of $16 million, some analysts speculated that the flag controversy was, in part, to blame.

This was the first film directed by Damien Chazelle to not be music-based.

Moments before the Apollo launch, one can see Armstrong's hand being placed on a T-shaped handle. This was the handle that would trigger the escape rockets mounted in the tower attached to the nose of the capsule which, in case of emergency, was designed to pull the capsule free from the rocket, taking it safely away from the rest of the vehicle.

Of the three top billed stars, none is from the United States.

After extensive research on the history of NASA, Damien Chazelle initiated operations at the Kennedy Space Center in Cape Canaveral and Johnson Space Center in Houston. The same goes for the cast of astronauts who followed a training camp.

In addition to serving as a docking target, the Agena was used to test a number of functions and procedures. The Gemini 8 mission was to test the ability to control the Agena from the Gemini, which among other things included the task of firing the Agena's engine in order to boost itself and the docked craft to a higher orbit.

The film won an Academy Award for Best Visual Effects.

This was director Damien Chazelle and Justin Hurwitz's fourth collaboration together, with the first three being Guy and Madeline on a Park Bench (2009), Whiplash (2014) and La La Land (2016).

Of the 12 men who have walked on the moon throughout the Apollo program, only 2 were civilians: Neil Armstrong and Apollo 17's Harrison Schmidt. All others were active USN and USAF officers. Buzz Aldrin was a USAF Colonel, his highest rank before retiring from the Air Force in 1972. The highest military rank attained by Armstrong was as a LTJG in the USN before resigning his commission in 1960. Armstrong also holds the distinction of becoming the first American civilian in space when he commanded the Gemini 8 mission in 1966.

Actor Jason Clarke, who played Apollo 1 astronaut Edward H. White II (Ed White), was born on July 17, 1969, one day into the Apollo 11 mission.

Jon Bernthal was cast but dropped out due to scheduling conflicts. He was replaced by Christopher Abbott.

The film brought together several Academy Award winners: director Damien Chazelle, screenwriter Josh Singer (Spotlight (2015)), director of photography Linus Sandgren (La La Land (2016)), editor Tom Cross (Whiplash (2014)), composer Justin Hurwitz (La La Land (2016)) and producer Steven Spielberg.

In the film Apollo 13 (1995) there is mention of Mount Marilyn, which is a mountain that Apollo 8 astronaut named for his wife. Although it is not shown in this film, when the Apollo 11 LEM is coming in for its landing, it passes over Mount Marilyn.

The film premiered at the Venice Film Festival in August 2018.

The third consecutive film by Damien Chazelle to be Oscar-nominated. However, as of 2019, First Man has the lowest Oscar count of any of his films. It also marks the first time he was not personally nominated, nor any of his actors, nor many of his frequent collaborators (cinematographer Linus Sandgren, film editor Tom Cross, and composer Justin Hurwitz).

There are two deleted scenes in the film: ''Apollo 8 Launch'' and ''House Fire."

The film had a four-minute IMAX preview that played before Mission: Impossible - Fallout (2018). This was the second occasion where a Universal Pictures film had an IMAX preview after the 3-D re-release of Jurassic Park (1993), which had a four-minute preview that preceded Oz The Great and Powerful (2013).

This was Damien Chazelle's and Ryan Gosling's second collaboration, the first being La La Land (2016).

Jason Clarke appears in the film as Edward H. White II. Clarke had previously starred as Sen. Ted Kennedy in Chappaquiddick (2017), which chronicled the Chappaquiddick incident that happened around the same time as the Apollo 11 moon landing. In Chappaquiddick's opening scene, Senator Kennedy is seen talking about JFK's promise to send men to the moon. The scene is followed by shots of a Saturn V/Apollo launch.

Jason Clarke and Kyle Chandler also co-starred in Zero Dark Thirty (2012).

Leon Bridges has a small role in the film. Ryan Gosling hosted Saturday Night Live for the first time with Leon Bridges as the musical guest in 2015.

Anna Chazelle: Damien Chazelle's sister plays a White House staffer.

Some of the voices heard in the film are actual recordings from the space program. For example, when Apollo 11 lands on the moon, the reply from Houston is the original. It is the voice of astronaut Charles Duke, who had the job of communicating with Apollo 11 during the landing. Neil Armstrong says, "Houston, Tranquility Base here, the Eagle Has Landed," then Charlie Duke says, "Roger, Tranquility, we copy you on the ground. You've got a bunch of guys about to turn blue. We're breathing again. Thanks a lot."

Janet Armstrong really did drive down to Mission Control after they cut off her "squawk box" during the Gemini-Agena mishap.

As indicated in the film, the Apollo I fire was caused by abrasion of some of the Teflon insulation from a wire. Unlike what is shown, the spark actually happened in a location out of sight. Even though oxygen is not flammable, a 100% oxygen atmosphere makes combustion extremely easy, even making aluminum flammable. Also, a great deal of Velcro-lined various surfaces within the spacecraft, as it was useful for restraining pens and other small items in a zero-g environment, such as is seen on the egress wrench. When under extreme pressure and heat in an all-oxygen environment, Velcro can burst into flame. The combination of arcing circuit, heat, and pressure of the oxygen caused the materials inside the capsule to ignite. As for the hatch, due to the malfunctioning explosive hatch bolts in Gus Grissom's Mercury flight, the hatch for the Apollo I was designed to maintain pressure. In order to open it, Ed White had to reach a lever above his head and pump it several times, after which the hatch would pull inwards and then swing out, somewhat like the doors of an airliner. If not for the Mercury malfunction, the Apollo I hatch would have had explosive bolts, in which case it is possible that at least one of the crew might have survived. An embarrassing discovery in the aftermath was that of a wrench that had been misplaced during capsule assembly and was found behind a sealed panel. While the wrench had nothing to do with the fire, it indicated a degree of carelessness in the assembly of the spacecraft.

The exact personal items that Neil Armstrong took on the Apollo 11 mission - his Personal Preference Kit or PPK - have never been disclosed by NASA, and Armstrong provided only a few remarks on the subject. (Parts of the Wright Flyer, donated by and returned to the US Air Force Museum; his fraternity pin; and "some Apollo 11 medallions, some jewelry for my wife and mother [a pin for each], and some things for other people".) Janet Armstrong does not believe that he carried any items for his sons. The book and the film speculate about what remaining items there might have been, however any such information will likely continue to be private.

Damien Chazelle keeps up his signature style of closing a movie with lead actors tangibly looking at each other without speaking. Both of his previous movies, Whiplash (2014) and La La Land (2016), had similar endings.

Neil Armstrong's famous quote as he stepped on the moon is the subject of historical controversy. The movie quotes accurately what was heard on Earth and in all recordings: "That's one small step for man, one giant leap for mankind." Armstrong later revealed that he intended to say "... one small step for [A] man ..." and that he thought he did, but all efforts to extract this from the recording, even with electronics, have been inconclusive.

The Apollo I astronauts survived the fire for only 17 seconds.

The depiction of the astronauts' quarantine in the finale is accurate. Most of their time was spent in the spacious and private Lunar Receiving Laboratory, not the infamously cramped trailer they used to get there. However, the face-to-face meeting with Janet Armstrong did not occur.

Contrary to popular belief and its depiction in many feature films, oxygen is not flammable. Instead, it acts as an oxidizer and causes other materials to burn, especially in high concentrations, such as inside the Apollo 1 capsule. Fire requires three elements: heat, fuel, and oxygen. The electrical short provided the heat. The aluminum, velcro, and other materials provided the fuel. The oxygen caused the heat to interact with the fuel.

When the film premiered at the Venice Film Festival, it faced controversy for not featuring the iconic planting of the American flag on the moon during the Lunar sequence. Ryan Gosling defended the omission, saying, "It transcended countries and borders...I think this was widely regarded in the end as a human achievement [and] that's how we chose to view it. I also think Neil was extremely humble, as were many of these astronauts, and time and time again he deferred the focus from himself to the 400,000 people who made the mission possible. I might have cognitive bias, [but] I don't think that Neil viewed himself as an American hero. From my interviews with his family and people that knew him, it was quite the opposite. And we wanted the film to reflect Neil." The biography upon which the film is based recounts the astronauts' struggles with the malfunctioning flagpole, which "nearly turned into a public relations disaster," in some detail.

On February 28, 1966, Elliot See, a former Navy aviator, was piloting a T-38 trainer with his Gemini crewmate Charlie Bassett. Accompanied by their Gemini backup crew, Gene Cernan and Tom Stafford, in a second T-38, they were flying from Ellington AFB to Lambert Field in St. Louis, where the four would spend a month with the Gemini simulator. Visibility was poor, requiring an instrument approach, and both planes overshot their landings. Stafford followed procedure for a missed landing but See, despite the conditions, thought that he could see the facility well enough to make a second attempt manually. As later stated by Cernan, See tended to be more tentative in his flying, which was problematic with the T-38, which did not perform well at low speeds. On this second attempt, See undershot the landing. At the last minute, he hit his afterburners and tried to turn but he did not have the initial speed required. The plane crashed into McDonnell Aircraft Building 101, where the Gemini 6 was built, some 500 feet from the spacecraft itself. Both See and Basett were killed instantly, with See being found in his ejection seat in a nearby parking lot, not having cleared the aircraft. See and Basset were the second and third such fatalities. Fellow third-group astronaut Ted Freeman had died on October 1, 1963 as the result of a goose striking his T-38 under foggy conditions. In order to avoid housing, Freeman turned and ejected horizontally due to being oriented nose-down. He was flying the exact opposite route of See and Basset, attempting a landing at Ellington while returning from simulator training in St. Louis.