Written by Kushal Byatnal on November 22, 2012 in Astronomy
Launched on November 14, 1969, Apollo 12 was the second manned flight to land on the moon. Mission Commander Charles Conrad and Lunar Module Pilot Alan Bean descended onto the lunar surface, while Command Module Pilot Richard Gordon remained in lunar orbit.
During the launch process, a discharge of lighting rocketed through the spacecraft and caused malfunctioning instruments, communications failure, and interrupted data readings. It was expected that the mission was to be aborted. However, Flight Controller John Aaron realized that he had seen this problem a year ago during a test run. When he had first encountered the problem, Aaron had taken the initiative and traced the problem back to the SCE (Signal Conditioning Equipment) system.
Apollo 12 during launch
Now when the problem arose during the real deal, he gave the command “Flight, try SCE to Aux”. Most of his colleagues at Mission Control had no idea what he was talking about – even the flight director asked Aaron to repeat the command. Even Conrad, who was aboard the spacecraft, said “What the hell is that?” Fortunately for the team, Alan Bean was able to draw upon his memory from a year ago when he had to locate the SCE switch during a simulated failure. He flipped the switch to auxiliary and the crisis was averted.
Initially, it was feared that the lighting discharge might have caused the command module’s parachute system to prematurely deploy. If this was the case, the crew would slam into the Pacific Ocean during re-entry and be killed on impact. However, Mission Control realized that there was no way to determine the status of the parachutes. As a result, this fact was kept hidden from the astronauts – rest assured, the parachutes did function normally upon re-entry.
The Lunar Module descending onto the Moon
***Fun Fact: After separation from the lunar module, the third stage of the Apollo 12 Saturn V rocket was supposed to be in solar orbit. This would be done by firing the propulsion system and then using the Moon’s gravity to sling-shot it orbit around the Sun. However, a slight miscalculation resulted in the object never achieving enough speed to escape the gravity of the Earth. It remained orbiting the Earth for nearly 2 years before escaping in 1971.
It returned to Earth’s orbit in 2002 and was discovered by amateur astronomer Bill Yeung. NASA was initially surprised by this finding because the possibility of it being an asteroid was ruled out. The only other explanation proposed was that it could have been a part of a spacecraft recently launched. Yet, NASA found that no recently launched spacecraft matched its orbit. By back-tracing its orbit, they found that it was in-fact the third stage of the Apollo 12 Saturn V rocket that had returned after nearly 31 years of orbiting the Sun.
The object left Earth’s orbit in 2003 and is expected to return in 2032.**
One of the goals of the Apollo 12 mission was to bring back the camera used on the Surveyor 3 rover sent in 1967. When the camera was analyzed on Earth, it was found that the bacterium Streptococcus mitis was found living on its surface. It was thought that the camera had not been properly sterilized two years ago (when the rover was first sent to the moon), and that the bacteria had survived on the lunar surface. Another possibility is that the camera was contaminated when it was analyzed back on Earth. There are strong arguments on both sides.
***Fun Fact: Bacteria being launched into space would have to endure radiation exposure, the vacuum of space, temperatures only 20 degrees above absolute zero, and no nutrient/water source. If the Surveyor 3 bacteria did indeed survive, they had to resist these conditions for over 2 years.***
Astronaut Alan Bean with Surveyor 3
One side reports that the proper precautionary measures were not taken upon the camera’s return. The other side claim that an analysis found only individual bacteria from one species – far from the characteristics of contamination (millions of bacteria from multiple species). Regardless of which side is correct, NASA used this incident to take strong measures in the future to prevent the accidental contamination of any potential life-harboring locations within our solar system.
For example, the most extreme case can be seen with the Galileo Spacecraft sent to Jupiter in 1989. Upon completing its data tests in 2003, NASA programmed the spacecraft to violently crash into Jupiter to avoid contaminating any of the surrounding moons with terrestrial bacteria. The impact speed of the spacecraft was over 173,000 km/h.
***Fun Fact: As a prank, the Apollo 12 backup crew managed to insert reduced-size photographs of Playboy playmates into lunar checklists. Astronauts Conrad and Bean discovered these while on the surface of the moon! Gordon, who remained in lunar orbit during the trip, found the November 1969 Playboy calendar hidden away in a locker. This calendar was put up for auction in 2011 for an estimated price between $12,000 and $16,000.
The backup crew who did this eventually went up into space themselves during the Apollo 15 mission.***
As you can tell, the Apollo 12 mission had a significant impact on space travel even today! The crew returned home during a solar eclipse and made it back safely, marking another major milestone for the human species.
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