Apollo program test flights proved the safety of their launch vehicle and spacecraft to carry astronauts safely, and four crewed missions followed shortly afterwards.
Neil Armstrong made history when he stepped off of the Lunar Module ladder on July 20, 1969 before hundreds of millions of viewers. His mission was to land in Descartes Highlands and conduct three lunar surface EVAs.
Apollo 8
President Kennedy declared his desire for humans to step foot on the Moon, and Apollo’s aim was to fulfill it. Through its unmanned test missions (known as Little Joe and Saturn I series) it developed technology necessary for human spaceflight; while manned flights tested systems including propulsion and EVAs. Astronauts resided within a command module attached to a service module providing power and support services; after each mission had concluded they split off to allow Lunar Module landing on its intended destination on the moon surface.
The initial four-minute and two-second lunar orbit insertion burn successfully placed the crew into a 70 by 193 mile lunar orbit, providing them with their first glimpse of the far side of the Moon and producing a picture known as an “Earthrise.”
Apollo 9
Details: This mission marked the inaugural test flight of Apollo spacecraft in Earth orbit, utilizing astronauts Jim McDivitt and Rusty Schweickart who used their Command Module (CM) as their home while their Lunar Module (LM) allowed for travel towards the Moon.
The Lunar Module, manufactured by Grumman Aircraft (later to become Northrop Grumman following their merger with Rockwell in 1967) was intended to land two astronauts on the lunar surface before returning them back to CSM after several days on its surface. Unfortunately, during its docking maneuver on Apollo 13, glare from the Sun made it difficult to see its overhead rendezvous window, leading McDivitt to comment: ‘That wasn’t docking; that was an eye test”.
This mission achieved its primary goals, such as testing out the Portable Life Support System which later crew members would rely on when working on the Moon, and conducting the first live television broadcast from space.
Apollo 10
Once Apollo 4, 5, and 6 had successfully taken to space, NASA engineers needed to test their system against an actual lunar trajectory. Their initial 1967 test flight plan called for E and F missions that would demonstrate lunar module docking with and returning to CSMs within lunar orbit.
On December 21st 1968, astronauts Frank Borman, James Lovell and William Anders made history when they launched from low Earth orbit on an accelerated schedule. For 10 days they conducted tests of various systems while sending live TV broadcasts home. On Christmas Eve they read from the Bible before sending live Christmas wishes back home. On day 12, they initiated Lunar Orbit Insertion tests utilizing Lunar Module engine; firing for 59 meter per second positive delta-v to simulate lunar landing operations (LOI). This simulation replicated exactly what an actual lunar landing would do on surface!
Apollo 11
Apollo 11 was known as the Moon Landing Mission because astronauts Armstrong and Aldrin made history by landing on its surface for three days at Hadley-Apennine, performing an extended Lunar Module (LM) stay, the initial use of Lunar Roving Vehicle, as well as several scientific experiments.
After practicing on the far side of the Moon, astronauts successfully docked their LM Spider with Gumdrop for their return journey home to Earth. While in flight they conducted tests of Ascent engine of LM before firing Eagle’s descent engine to enter an orbit that passed directly overhead of Sea of Tranquility.
Apollo 12
NASA responded to Apollo 11’s successful landing by conducting several missions with hybrid Lunar Module-CSM spacecraft that used both types of landing systems to land humans on the Moon, Apollo 12 being one such mission.
Commander David Scott and Lunar Module Pilot James Irwin conducted 18 hours of lunar surface EVAs in Hadley-Apennine region using first lunar rover for sampling 169 pounds of samples.
The crew also used this mission as an opportunity to test its seismometers by sending its LM ascent stage crashing onto the lunar surface, providing scientists with access to its seismometers for scientific study. It was one of many experiments performed during this voyage and marked its debut with astronauts driving on lunar terrain using “moon buggies” – another key step toward making space travel more routine for future missions.
Apollo 13
The final Apollo mission, which launched November 14, 1969, was an abbreviated visit to the Moon. Astronauts Charles “Pete” Conrad and Alan Bean survived two lightning strikes during liftoff, landing perfectly at Taurus-Littrow Ocean of Storms with pinpoint accuracy. Their EVA was by far the longest of any mission as well as possibly being its most complex; heat flow tests were performed while Einstein’s theory of relativity predicted gravity waves that may have been measured during EVA time.
Jack Swigert heard a loud bang during a power system test of Odyssey and radioed back to Earth: “Houston, we have a problem here”. An oxygen tank had ruptured while traveling toward the Moon and crippled their craft; after which, they relocated into lunar module Aquarius before swinging around on an emergency return trajectory back home – leaving an unparalleled legacy behind them.
Apollo 14
Apollo 14 mission, conducted from 31 January to 9 February 1971, was the second manned flight to land in lunar highlands. Armstrong and Aldrin un-docked their lunar module (nicknamed Eagle) from their command module (CSM), then used a launch mechanism to drop it onto Moon surface.
The astronauts collected 382 kilograms of rocks and soil samples to bring back to Earth for further study by scientists, helping them understand how the Moon formed over 3.8 billion years ago, as well as demonstrating that Earth and Moon share chemical relationships.
Shepard made history when he became the oldest person ever to walk on the Moon over two EVA periods that totaled 4 hours, 49 minutes GET. Meanwhile, Roosa used an Advanced Lunar Science Experiment Package (ALSEP) while panoramic and mapping cameras provided coverage of more of the surface than previous missions had offered.
Apollo 15
Apollo 15’s crew became the first to spend three days exploring lunar surfaces, opening up more opportunities for surface exploration. They also made history as they used an extended lunar module (LM) for orbital science experiments and performed numerous orbital science tests during their mission.
Apollo astronauts brought back samples of lunar rock and regolith that have provided scientists with invaluable insights about our Moon. Furthermore, the samples have helped scientists gain a greater understanding of solar wind circulation patterns as well as other aspects of space travel.
Apollo 15 marked the debut of “J” missions, adding a scientific instrument module to the service module (SM) for systematic orbital remote sensing via panoramic and mapping cameras; x-ray and gamma-ray spectrometers to measure elemental composition; and laser altimeters for topography measurements. Astronauts Charles Conrad and Alan Bean used this lunar module (LM) for two extended EVAs as well as setting up and operating lunar surface scientific experiments.
Apollo 16
The final Apollo mission centered on Descartes region of lunar highlands. Lunar Module (LM) astronauts explored two geologic units while collecting samples of rock and regolith (the impact-generated layer that makes up its surface). Over half a century, scientists have used these samples to shed new light on Moon origin and evolution.
This was the inaugural Lunar Roving Vehicle mission and it successfully landed in Hadley-Apennine region of the Moon and collected additional samples over three days, led by John Young with Thomas “Ken” Mattingly and Charles Duke in LM; its launch took place April 16, 1972 by Saturn V rocket; its CSM separated in lunar orbit with each carrying its own name derived from cartoon character names.
Apollo 17
Alan Shepard and Buzz Aldrin’s final Apollo flight of the decade marked the first precise manned lunar landing ever, using both Lunar Roving Vehicle technology as well as featuring professional geologists aboard for analysis purposes.
The crew spent three days exploring craters on the Moon, conducting two EVAs to retrieve Surveyor 3 probe and deploy various experiments on its surface. Furthermore, they tested its thermal properties as well as tested thermal properties of lunar surface.
Apollo 15 and 16 astronauts utilized the Scientific Instrument Module (SIM bay) for systematic orbital remote sensing of large areas of the Moon’s surface. Their research helped refine a model for its formation while they discovered new lava flows and measured gravity waves.