Apollo 12

• 1. The Navy Crew And The Moon

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  the 14th of November 1969 marked the start of a six-day journey for three men from the United States Navy. Commander Charles Pete Conrad was thirty-nine years old when he launched from Kennedy Space Center in Florida. He had earned an aeronautical engineering degree from Princeton University in 1953 before becoming a naval aviator. His crewmate Richard Dick Gordon was forty and held a chemistry degree from the University of Washington. They both completed test pilot school at Patuxent River Naval Air Station. Lunar Module Pilot Alan Bean was thirty-seven and graduated from the University of Texas with an engineering degree in 1955. All three were commanders in the Navy when they flew this mission. Conrad had previously flown on Gemini 5 and commanded Gemini 11. Gordon flew alongside Conrad on that same Gemini 11 flight. Bean first entered space as part of this Apollo 12 crew after serving as a backup for Apollo 9 earlier in 1969. The original Lunar Module pilot assigned to work with Conrad was Clifton C. Williams Jr. Williams died in October 1967 when his T-38 jet crashed near Tallahassee. Conrad asked for Bean again after Williams death and Deke Slayton finally agreed. Bean had been unavailable due to an assignment to the Apollo Applications Program. The backup crew included David R Scott Alfred M Worden and James B Irwin who later became the crew of Apollo 15.

• 2. Pinpointing The Surveyor Probe

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  NASA planners chose a landing site in the Ocean of Storms based on scientific goals rather than safety margins alone. The target was a crater where the Surveyor 3 robotic probe had landed on the 20th of April 1967. Engineers at the Manned Spaceflight Center in Houston argued for a landing close enough to allow astronauts to cut parts from it for return to Earth. Apollo Program Manager Samuel Phillips designated what became known as Surveyor crater as the landing site on the 25th of July 1969. This decision went against the unanimous opposition of members of two site selection boards. Some NASA administrators feared Apollo 12 would land far enough away that the astronauts could not reach the probe. They worried the agency would be embarrassed if they failed to perform a precision landing. Ewen Whitaker helped locate Surveyor 3 by studying images from the probe and comparing them with photographs of thousands of similar craters under a microscope. He identified two rocks near Surveyor 3 that led to the identification of the probes location. Conrad trained to expect a pattern of craters known as the Snowman to be visible when the craft underwent pitchover. He was astonished to see the Snowman right where it should be during the descent. He took over manual control and planned to land the LM in an area near the Surveyor crater dubbed Pete's Parking Lot. The final touchdown occurred at 110:32:36.2 UTC on the 19th of November 1969 just 180 meters from the Surveyor probe.

• 3. Lightning Strikes And System Recovery

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  A rainy day at Kennedy Space Center brought strong winds of up to forty miles per hour during ascent. Lightning struck the Saturn V rocket thirty-six point five seconds after lift-off triggered by the vehicle itself. The static discharge caused a voltage transient that knocked all three fuel cells offline. A second strike at fifty-two seconds knocked out the eight-ball attitude indicator. The telemetry stream at Mission Control became garbled but the Saturn V continued to fly normally. The strikes had not affected the Saturn V instrument unit guidance system which functioned independently from the Command Module. The astronauts unexpectedly found a board red with caution and warning lights yet could not tell exactly what was wrong. John Aaron Electrical Environmental and Consumables Manager in Mission Control remembered the telemetry failure pattern from an earlier test. He knew how to fix it because he recalled a power loss causing a malfunction in the CSM signal conditioning electronics. Aaron made a call saying Flight EECOM Try SCE to Aux to switch the SCE to a backup power supply. Bean who as LMP was the spacecraft's engineer knew where to find it and threw the switch. Afterward the telemetry came back online revealing no significant malfunctions. Bean put the fuel cells back online and the mission continued. Once in Earth parking orbit the crew carefully checked out their spacecraft before re-igniting the S-IVB third stage for trans-lunar injection. The lightning strikes caused no serious permanent damage.

• 4. Two Moonwalks And Sample Collection

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  Conrad stepped onto the lunar surface first and said Whoopie Man that may have been a small one for Neil but that's a long one for me. This remark was part of a bet with reporter Oriana Fallaci regarding whether NASA instructed Neil Armstrong on his first words. Conrad later said he was never able to collect the money from her. Bean carried a color television camera to the place near the LM where it was to be set up. He inadvertently pointed it directly into the Sun destroying the Secondary Electron Conduction tube. Television coverage of this mission terminated almost immediately after the accident. The first EVA lasted three hours fifty-six minutes and three seconds while they deployed the Apollo Lunar Surface Experiments Package. Bean had trouble extracting the RTG's plutonium fuel element from its protective cask. The astronauts resorted to using a hammer to hit the cask and dislodge the fuel element. They secured a core tube full of lunar material and collected other samples during the first walk. Four possible geologic traverses had been planned based on variable landing points. Scientists in Houston combined two of the traverses into one that Conrad and Bean could follow from their landing point. The resultant traverse resembled a rough circle. Their first stop was Head crater some 180 meters from the LM. Bean noticed that Conrad's footprints showed lighter material underneath indicating the presence of ejecta from Copernicus crater. The second EVA lasted three hours forty-nine minutes fifteen seconds during which they traveled 450 meters. They went as far as 720 meters from the LM and collected 34 kilograms of samples.

• 5. Seismic Instruments And Solar Wind

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  The Apollo Lunar Surface Experiments Package included a Passive Seismic Experiment designed to measure moonquakes and other movements in the Moon's crust. It would be calibrated by the nearby planned impact of the ascent stage of Apollo 12's LM. This object of known mass and velocity hitting the Moon at a known location projected to be equivalent to the explosive force of one ton of TNT. A Lunar Surface Magnetometer measured the magnetic field at the Moon's surface while a Lunar Atmosphere Detector intended to measure density and temperature of the thin lunar atmosphere. A Dust Detector used to measure accumulation of lunar dust on the equipment completed the suite of instruments. The experiments were powered by SNAP-27 a radioisotope thermoelectric generator developed by the Atomic Energy Commission. Containing plutonium the RTG flown on Apollo 12 was the first use of atomic energy on a crewed NASA spacecraft. The plutonium core was brought from Earth in a cask attached to an LM landing leg. The ALSEP experiments left on the Moon by Apollo 12 were connected to a Central Station containing a transmitter receiver timer data processor and equipment for power distribution. The LAD returned only a small amount of useful data due to failure of its power supply soon after activation. The LSM was deactivated on the 14th of June 1974 as was the other LSM deployed on the Moon from Apollo 15. All powered ALSEP experiments that remained active were deactivated on the 30th of September 1977 principally because of budgetary constraints.

• 6. Return Journey And Ocean Recovery

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  LM Intrepid lifted off from the Moon at mission time 143:03:47.78 or 14:25:47 UTC on the 20th of November 1969. After several maneuvers CSM and LM docked three and a half hours later. At 147:59:31.6 the LM ascent stage was jettisoned and shortly thereafter the CSM maneuvered away. Under control from Earth the LM's remaining propellant was depleted in a burn that caused it to impact the Moon 1,800 meters from the Apollo 12 landing point. The seismometer the astronauts had left on the lunar surface registered the resulting vibrations for more than an hour. A final television broadcast occurred with the astronauts answering questions submitted by the media. One event was the photography of a solar eclipse that occurred when the Earth came between the spacecraft and the Sun. Bean described it as the most spectacular sight of the mission. Yankee Clipper returned to Earth on the 24th of November 1969 splashing down in the South Pacific Ocean southeast of Samoa at 244:36:25. The landing was hard resulting in a camera becoming dislodged and striking Bean in the forehead. After recovery they entered the Mobile Quarantine Facility while lunar samples and Surveyor parts were sent ahead by air to the Lunar Receiving Laboratory in Houston. Once the Hornet docked in Hawaii the MQF was offloaded and flown to Ellington Air Force Base near Houston on November 29. From there it was taken to the LRL where the astronauts remained until released from quarantine on December 10.

• 7. Legacy And Modern Reconnaissance

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  Conrad urged his crewmates to join him in the Skylab program seeing in it the best chance of flying in space again. Bean did so while Conrad commanded Skylab 2 and Bean commanded Skylab 3. Gordon though still hoped to walk on the Moon and remained with the Apollo program serving as backup commander of Apollo 15. He was the likely commander of Apollo 18 but that mission was canceled and he did not fly in space again. The Apollo 12 command module Yankee Clipper was displayed at the Paris Air Show and then placed at NASA's Langley Research Center in Hampton Virginia. Ownership transferred to the Smithsonian in July 1971. It is now on display at the Virginia Air and Space Center in Hampton. In 2009 the Lunar Reconnaissance Orbiter photographed the Apollo 12 landing site where the descent stage ALSEP Surveyor 3 spacecraft and astronaut footpaths remain. In 2011 the LRO returned to the landing site at a lower altitude to take higher resolution photographs. The ascent stage of LM Intrepid impacted the Moon the 20th of November 1969 at 22:17:17.7 UT. Mission Control had remotely fired the service module's thrusters after jettison hoping to have it skip off the atmosphere and enter a high-apogee orbit. The S-IVB is in a solar orbit that is sometimes affected by the Earth.