As it descended, Eagle encountered issues not anticipated in simulations. Multiple alarms went off due to too many tasks being attempted at once by its computer system.
Armstrong and Aldrin spent 21 hours 38 minutes on the moon’s surface before returning to Collins in Columbia’s command module, using seismometers and laser reflectors to measure distances from Earth to Moon as well as collecting samples.
The Launch
2019 marked the 50th anniversary of Apollo 11’s landing, marking a pivotal event in human history: humans first setting foot on another planet for the first time ever! For those involved, this momentous occasion marked both personal and technological triumph.
Neil Armstrong, Buzz Aldrin and Michael Collins boarded NASA’s Saturn V rocket at Kennedy Space Center in Florida on July 16, 1969 for launch into lunar orbit on the afternoon of July 19. On the following day they commenced descent in Lunar Module Eagle; selecting an area in the Sea of Tranquility previously surveyed by Apollo 10 during its flight towards the Moon for their landing site selection.
Armstrong and Aldrin activated the lunar module descent engine for 756.3 seconds in order to start powered descent, with this action bringing them closer to the Moon at an approximate four foot per second rate.
Armstrong and Aldrin utilized scientific equipment on the lunar surface, such as a television camera, solar wind composition experiment, seismology instrument package, and Laser Ranging Retroreflector. They collected rock samples, took photographs of lunar terrain and their LM, collected data for transmission back to Earth and kept constant communication with Mission Control in Houston.
Before the lunar voyage began, several tragic events had rocked the United States. Space program oversight had come under intense scrutiny following three astronaut deaths during a manned Saturn rocket and spacecraft test at Cape Canaveral on January 27, 1967, just weeks prior to Apollo 11 being launched; at that same time racial unrest flared across the nation just prior to launch of Apollo 11. These incidents served as reminders of America’s challenges while heightening urgency to reach for the Moon.
The Flight
At an incredible achievement that transfixed millions of people worldwide. Today it can be easy to forget just how extraordinary and extraordinary this space machine was at the time; reading through mission transcripts makes one realize just how demanding and engrossing was the experience of flying it; astronauts had a full checklist to run before leaving Earth; they also needed to adapt their bodies to low gravity of Moon life while dealing with various technical issues such as power generation and navigation issues.
Once in lunar orbit, the crew began preparations for an EVA (extravehicular activity). This took several hours while Commander Armstrong and Lunar Module Pilot Aldrin rested for approximately 10 hours each night before commencing this endeavor.
As soon as the EVA began, its computers were distracted by one of many “1202” alarms; these errors in the computer program caused too many tasks to be processed simultaneously by the system. Although crew managed to work around these problems successfully, some tasks on EVA needed to be postponed until later dates.
Once they were prepared for their initial moonwalk, Armstrong took off on his iconic phrase: “That’s one small step for man, one giant leap for mankind!” They exited the Lunar Module at 2:56 PM and Armstrong quickly made history when he made history by proclaiming, “That’s one small step for man, one giant leap for mankind!”
The astronauts spent 2.5 hours exploring the Moon. They conducted science and engineering experiments, deployed science cameras, photographed their surroundings, read an inscription plaque on its surface, collected rock samples for later analysis back home on Earth, deployed seismometers to monitor moonquakes, as well as placing laser retroreflectors for precise measurements on the lunar surface.
Armstrong and Aldrin completed their two-hour, 31-minute lunar EVA without incident and returned to the LM for another three hours before firing their reentry engines and returning home safely. This EVA was their sole task before their journey home took place smoothly.
The Landing
As Armstrong and Aldrin made history on the Moon, all eyes turned their way. After exiting their lunar module (LM) and walking onto its surface, Armstrong radioed back to Mission Control: “That is one small step for man, one giant leap for mankind!”
Soon thereafter, astronaut Michael Collins boarded the Command Module (CM), which separated from the Lunar Module (LM) as planned and launched its descent engine to drop into an elliptical lunar orbit with an approximate low point around 15,000 feet below lunar surface.
Lunar orbit insertion was accomplished successfully, as Armstrong fired his second time to initiate powered descent towards the lunar surface. Neufeld describes this final two-hour period as being extremely “critical and dangerous”, forcing Armstrong to navigate his 32,000-pound LM through boulder-strewn lunar terrain and down to Site 2.
While waiting for their Earth Return Vehicle to dock with the CM, Armstrong and Aldrin completed an extravehicular activity lasting two hours and 31 minutes on the Moon. While retrieving scientific instruments – such as seismometers for monitoring moonquakes and laser retroreflectors to measure distance between Earth and Moon – Armstrong also set up an American flag and commemorative plaque, and briefly spoke with President Richard Nixon.
After performing a thorough check of Eagle, the astronauts prepared to exit. Armstrong made his historic journey onto the lunar surface at 9:56 p.m. — saying his famous words: “That’s one small step for man, one giant leap for mankind”. Aldrin soon joined him.
Armstrong had complete faith that their experience and the meticulous planning provided by NASA’s simulators would carry them through. Armstrong was right; they landed with less than 30 seconds of reserve fuel remaining. Once in their command module Eagle, Armstrong successfully utilized Eagle’s ascent engine and executed another daring maneuver: disengaging from it before jettisoning it back into Earth’s atmosphere.
The Return
At a time when many still saw the world as divided, Neil Armstrong and Buzz Aldrin’s triumphant return from space marked an inspiring moment of reconciliation and global unification. Their mission fulfilled President Kennedy’s 1961 goal of sending astronauts to the Moon before the end of the 1960s; it also laid the groundwork for five subsequent lunar landing missions and brought back substantial amounts of rock and soil that helped scientists understand our planet better.
Armstrong and Aldrin un-docked Eagle from Columbia at 1am local time on 20 July while still in lunar orbit, performing maneuvers to achieve an initial lunar orbit of 111 by 306 kilometers before firing up their descent engine for powered descent towards its surface.
At 02:56:15 UTC, they entered the Sea of Tranquility and initiated a two and half hour extravehicular activity (EVA), during which time they deployed science experiments, photographed their surroundings, displayed an American flag, read President Richard Nixon’s signature plaque and collected rock and soil samples for further analysis here on Earth. Furthermore, they provided verbal descriptions to geologists back on Earth while remaining in communication with mission control in Houston throughout this EVA.
Once their work was complete, the astronauts returned to Eagle and met Collins back at Columbia. Utilizing its service propulsion system, they lowered their lunar orbit until it passed just above it; then used fire it once more to initiate their long trip back toward Earth.
Reihm recognized this was an essential component of their mission; without it, they would never reach home. He felt confident in the spacesuits he designed; each had been tested, tweaked and tailored specifically for this momentous moment – should the astronauts hit hard on a Moon rock landing, tears wouldn’t pose too much of a problem he thought. Reihm would experience it all with pride as an engineer for himself as part of their success on their job – it was glorious yet frightening at the same time!