Just three years after the launch of Apollo 4, NASA was ready to launch what would become the most significant mission in the history of space exploration, Apollo 11. It would come to define John F Kennedy’s lost presidency and make household names of Buzz Aldrin and Neil Armstrong.
The three-man Apollo 11 crew was announced on November 20, 1967. Neil Armstrong secured the Commander’s seat while Jim Lovell and Buzz Aldrin would pilot the Command Module and Lunar Module respectively. However, Lovell would replace Michael Collins on the crew of Apollo 8 after the latter required surgery, with Collins then replacing Lovell on the crew of Apollo 11 as a result of NASA crew rotations. The substitution would also see Lovell securing a seat aboard the ill-fated Apollo 13 mission. This bizarre set of unrelated events would cement Lovell’s name into the history books as the only person to travel to the moon twice without ever setting foot on it.
The 110.6-meter (363-foot) Saturn V rocket carrying the three astronauts, Command/Service Module (CSM) and Lunar Module (LM) launched from Pad 39A at the Kennedy Space Center in Florida on July 16, 1969, at 13:32 UTC. People from around the country crowded highways and beaches near the launch site with millions more from around the world tuning into the televised broadcast. As the launch approached, excitement grew and as the countdown hit zero, the titanic rocket thundered upwards. Just twelve minutes and two stage separations later, the Saturn V upper stage carrying its precious payload entered into an orbit around Earth. Once in orbit, the Saturn V’s upper stage engine fired pushing the spacecraft into a trans-lunar injection completing the first major milestone of the mission.
Before settling down for their trip to the moon, the crew performed the transposition, docking, and extraction maneuver. The maneuver separated the CSM from the rocket’s upper stage, turned it around and docked it with the LM still attached to the upper stage. The now paired CSM and LM spacecraft were then separated from the spent upper stage which entered into a trajectory taking it past the moon. Aside from a minor velocity correction and a 36-minute televised broadcast, the crew spent much of the next two days busying themselves with spacecraft operations.
On July 19 at 17:21, the Apollo 11 spacecraft passed behind the Moon. The spacecraft fired its service propulsion engine and successfully entered into a lunar orbit. Before moving forward, the crew orbited the Moon thirty times studying their landing site in the southern Sea of Tranquility. The landing site had been scouted by the Ranger 8 and Surveyor 5 landers and was chosen because of its relatively flat surface. Late the next day on July 20, 1969, Neil Armstrong and Buzz Aldrin sealed themselves inside the LM, designated Eagle and separate from Collins who remained aboard the CMS. After a short visual inspection by Collins to ensure the LM had not been damaged, Armstrong and Aldrin began their descent.
Although the mission had, until that point proceeded without incident, the descent to the lunar surface would not be a smooth one. Soon after Armstrong and Aldrin began their descent, they realised that they were passing surface landmarks at least four seconds earlier than they should have been. This indicated that they would miss the landing zone by several kilometers and would like have to make adjustments closer to the ground. Then, at around 1,800 meters (6,000 feet) from the surface, the spacecraft’s guidance computer reported unexpected 1202 and 1201 errors. After referring the issue to NASA ground control (Houston), they were told to ignore it and continue with the descent. It was later found that a radar switch had been left in the wrong position due to an error in the checklist manual. The computer had, as a result, been flooded with more calculations than it could complete. Luckily, Apollo software engineers had programmed the guidance computer to ignore lower priority tasks when it was overloaded allowing it to focus on what was most important, landing safely. As they continued to descend, Armstrong released that they the flight computer was guiding the spacecraft towards a boulder-strewn area and took semi-automatic control with Aldrin supplying altitude and velocity data.
After an event-filled descent, the LM touched down on the surface of the moon at 20:17:40 UTC on Sunday, July 20 with barely 25 seconds of fuel remaining. As Aldrin and Armstrong went through shutdown procedures, Charles Duke (Houston CAPCOM for the landing phasing) acknowledge touchdown saying, “We copy you down, Eagle.” Moments later Armstrong responding with the now famous words, “Houston, Tranquility Base here. The Eagle has landed.”
Although originally scheduled for a 5-hour rest period, both astronauts reported they would not be able to sleep and began preparing for their EVA (extravehicular activity). At 02:51 UTC on July 21, Neil Armstrong exited the LM and began his descent down the ladder and onto the lunar surface. During the descent, he deployed the Modular Equipment Stowage Assembly (MESA) attached to the side of the LM and activated the TV camera that would capture the historic moment. At 02:56:15 UTC, he placed his left foot on the surface of the Moon and declared, “That’s one small step for [a] man, one giant leap for mankind.” Although most remember Armstrong’s declaration without the “a”, it was later discovered that radio static had drowned it out resulting in possibly one of the most famous misquotes of all time.
Once on the surface, Armstrong collected a contingency soil sample and secured it inside the pocket on his right thigh. It was a guarantee that should there be an emergency, they would still return with at least a small sample. Aldrin joined Armstrong on the surface twenty minutes later describing the landscape as, “Magnificent desolation.” During the 2 hours and 31 minutes that followed, the astronauts collected 21.55 kilograms (47.51) of soil and rock samples, took pictures and video, planted a flag, and placed the Early Apollo Scientific Experiment Package (EASEP). While on the surface, President Richard Nixon also spoke to the astronauts through a telephone-radio transmission. In addition to noting that the call was “the most historic phone call ever made form the White House”, Nixon conveyed his and the nation’s pride at their accomplishment and expressed that, “Because of what you have done, the heavens have become part of man’s world.”
Before sealing the hatch after returning from their EVA, Aldrin and Armstrong tossed out their PLSS backpacks, one Hasselblad camera and various other equipment that would no longer be necessary, lightning the spacecraft’s ascent stage. The pair then settled in for seven hours of rest.
Two hours before they were set to depart the lunar surface, Aldrin and Armstrong received their wakeup call from Houston. At 17:45 UTC on July 21, after a little more than 21 hours on the lunar surface, Eagle’s ascent stage lifted off to rejoin Collins aboard the CSM in orbit. During the ascent, Aldrin noted that the exhaust from the LM rocket had blown away the flag the astronauts had placed on the surface. Later Apollo missions would consequently plant their flags further away from their landing site.
Armstrong, Aldrin, and Collins returned safely to Earth splashing down in the Pacific Ocean at 16:51 UTC on July 24. The crew was recovered by Navy personnel and transported to the recovery vessel, the USS Hornet. Shortly afterward, they were ushered into quarantine. The Apollo 11 crew were one of only three crews (Apollo 12 and Apollo 14 being the others) to undergo quarantine. Following Apollo 14, it was determined that the moon was indeed barren of all life and that quarantine processes were not necessary.
The crew of Apollo 11 were welcomed back as heroes. On August 13, 1969, a parade was thrown in their honour and attended by President Nixon, Vice President Spiro T. Agnew, ambassadors from 83 nations, the Chief Justice and no fewer than 44 governors.
Apollo 11 was the culmination of not just the nine years of work that followed the creation of the Apollo programme, but the decades of research and experimentation that it proceeded. It is a symbol for what’s possible when scientists are given funding approaching that of a country’s generals. It has and will continue to inspire entrepreneurs, researchers, scientists, engineers, budding astronauts and even the odd writer. Although several lunar missions followed it, it is Apollo 11 and the brave men who conquered the unknown that we continue to celebrate almost 50 years later.
