Tuesday, September 25, 2007
Apollo 12 was the sixth manned mission in the Apollo program and the second to land on the Moon.
David Scott (flew on Gemini 8, Apollo 9, Apollo 15), commander
Alfred Worden (flew on Apollo 15), command module pilot
James Irwin (flew on Apollo 15), lunar module pilot Backup crew
Gerald Carr (flew on Skylab 4)
Edward Gibson (flew on Skylab 4)
Paul Weitz (flew on Skylab 2, STS-6) Support crew
Gerald Griffin, Gold team
Pete Frank, Orange team
Cliff Charlesworth, Green team
Milton Windler, Maroon team Flight directors
Landing Site: W 3.01239 S - 23.42157 W or 3° 0' 44.60" S - 23° 25' 17.65" W Mission parameters
Undocked: November 19, 1969 – 04:16:02 UTC
Redocked: November 20, 1969 – 17:58:20 UTC LM — CSM docking
Conrad — EVA 1
Stepped onto Moon: 11:44:22 UTC
LM ingress: 15:27:17 UTC
Bean — EVA 1
Stepped onto Moon: 12:13:50 UTC
LM ingress: 15:14:18 UTC EVA 1 start: November 19, 1969, 11:32:35 UTC
Duration: 3 hours, 56 minutes, 03 seconds EVA 1 end: November 19, 15:28:38 UTC
Conrad — EVA 2
Stepped onto Moon: 03:59:00 UTC
LM ingress: 07:42:00 UTC
Bean — EVA 2
Stepped onto Moon: 04:06:00 UTC
LM ingress: 07:30:00 UTC EVA 2 start: November 20, 1969, 03:54:45 UTC
Duration: 3 hours, 49 minutes, 15 seconds Quotations
Shortly after lift-off from Kennedy Space Center, the Saturn V rocket body was hit by a bolt of upper-atmosphere lightning. The CM's instruments momentarily went off-line and Mission Control lost the telemetry feeds from the spacecraft for several seconds. When ground control regained telemetry lock with the spacecraft, the feeds were garbled and reported incomplete and possibly inaccurate information. EECOM John Aaron thought that the garbled telemetry might be caused by a malfunction in the launch vehicle's Signal Conditioning Equipment (SCE), since the SCE converted raw instrument data into forms usable by spacecraft instrument displays and ground telemetry equipment (source), and it would have automatically gone off-line in response to the kind of disruption to the spacecraft's electrical systems that a lightning strike would cause (source).
With this in mind, Aaron suggested the crew "Try SCE to aux" – thereby forcing the SCE to switch over to its auxiliary power source and bringing the SCE back on-line. The command was a relatively obscure one and neither the Flight Director, CAPCOM, or Mission Commander Conrad could immediately recall how to implement it; however, lunar module pilot Al Bean remembered that the SCE switch was on his panel because of a training incident a year prior to launch where just such a failure had been simulated. Aaron's quick thinking and Bean's memory were able to salvage what otherwise would have been an aborted mission (at the time of the failure, the flight had just entered abort mode One Bravo). With telemetry restored, the crew proceeded to parking orbit and was able to fully restore and verify the functionality of their spacecraft before re-igniting the S-IVB third stage for trans-lunar injection.
The S-IVB was originally intended to be put into a solar orbit by venting the remaining propellant. However, an extra long burn of the ullage motors meant that venting the remaining propellant in the tank of the S-IVB did not give the rocket stage enough energy to escape the Earth-Moon system and instead the stage ended up in a semi-stable orbit around the Earth after passing by the Moon in November 18, 1969. It finally entered into solar orbit 1971, but returned to Earth orbit (briefly) 31 years later. It was discovered by amateur astronomer Bill Yeung and he gave it the temporary designation J002E3 before it was determined to be an artificial object.
The Apollo 12 mission landed on an area of the Ocean of Storms that had been visited earlier by several unmanned missions (Luna 5, Surveyor 3, and Ranger 7). The International Astronomical Union, recognizing this, christened this region Mare Cognitium (Known Sea). The landing site would thereafter be listed as Statio Cognitium on lunar maps (Conrad and Bean did not formally name their landing site, interestingly enough, though the intended touchdown point was nicknamed Pete's Parking Lot by Conrad).
The second lunar landing was an exercise in precision targeting. The descent was automatic, with only a few manual corrections by Conrad. Although Apollo 11 had made an almost embarrassingly imprecise landing well outside the designated target area, Apollo 12 succeeded, on November 19, in making a pin-point landing, within walking distance (less than 200 meters) of the Surveyor 3 probe, which had landed on the Moon in April 1967.
Conrad actually landed Intrepid 580 feet short of Pete's Parking Lot because the planned landing point looked rougher than anticipated during the final approach to touchdown. The planned landing point was a little under 1180 feet from Surveyor 3, a distance that was chosen to eliminate the possibility of lunar dust (being kicked up by Intrepid's descent engine during landing) from covering Surveyor 3. But the actual touchdown point — 600 feet from Surveyor 3 — did cause a thin film of dust to coat the probe, giving it a light tan hue.
To improve the quality of television pictures from the Moon, a color camera was carried on Apollo 12 (unlike the monochrome camera that was used on Apollo 11). Unfortunately, when Bean carried the camera to the place near the lunar module where it was to be set up, he inadvertently pointed it directly into the Sun, destroying the vidicon tube. Television coverage of this mission was thus terminated almost immediately.
Conrad and Bean removed pieces of the Surveyor 3, to be taken back to Earth for analysis, and took two Moon-walks lasting just under four hours each. It is widely claimed that a common bacterium, Streptococcus mitis, was found to have accidentally contaminated the spacecraft's camera prior to launch and survived dormant in this harsh environment for two and a half years . However, this claim is no longer taken seriously by NASA (see Myth of Streptococcus mitis on the moon).
Astronauts Conrad and Bean also collected rocks and set up equipment that took measurements of the Moon's seismicity, solar wind flux and magnetic field, and relayed the measurements to Earth. (By accident Bean left several rolls of exposed film on the lunar surface.) Meanwhile Gordon, on board the Yankee Clipper in lunar orbit, took multispectral photographs of the surface.
The lunar plaque attached to the descent stage of Intrepid is unique in that unlike the other lunar plaques, it (a) did not have a depiction of the Earth, and (b) it was textured differently (the other plaques had black lettering on polished stainless steel while the Apollo 12 plaque had the lettering in polished stainless steel while the background was brushed flat).
Intrepid's ascent stage was dropped (per normal procedures) after Conrad and Bean rejoined Gordon in orbit. It impacted the Moon on 20 November 1969 at 3.94 S, 21.20 W. The seismometers the astronauts had left on the lunar surface registered the vibrations for more than an hour.
The crew stayed an extra day in lunar orbit taking photographs, for a total lunar stay of thirty-one and a half hours.
Yankee Clipper landed on 24 November 1969, at 20:58 UTC (3:58pm EST, 10:58am HST), approximately 500 miles (800 km) east of American Samoa. During landing, a 16 mm camera dislodged from storage and struck Bean in the forehead, rendering him briefly unconscious. He suffered a mild concussion, and needed six stitches.
The Yankee Clipper is displayed at the Virginia Air and Space Center, Hampton, Virginia. Its recovery ship, the USS Hornet, is now open to the public as a museum in Alameda, California.
The Surveyor 3 camera retrieved by the Apollo 12 astronauts now resides in the Exploring the Planets gallery at the National Air and Space Museum.
Alan Bean smuggled a camera-shutter self-timer device on to the mission with the intent of taking a photograph with himself, Pete Conrad and the Surveyor 3 probe in the frame. As the timer was not part of their standard equipment, such an image would have thrown post-mission photo analysts into confusion over how the photo was taken. However, the self-timer was misplaced during the EVA and the plan was never executed.
The Apollo 12 backup crew managed to 'insert' into the astronaut's lunar checklist (attached to the wrists of Conrad's and Bean's spacesuits) reduced sized pictures of Playboy centerfolds, thus introducing pornography to the moon for the first time when Conrad and Bean were looking through the lists during their first EVA. A PDF with the photocopies of their cuff checklists on the Lunar Surface Journal website still have these photos.  The checklists also contained a page of pre-prepared complex geological terminology at the back, to be used for the confusion of the ground crew.
Another idea that did not materialize was that Conrad — who loved collecting baseball caps — had a giant one made that would fit over his space helmet. He wanted to wear it during his lunar EVAs, but there was no way that it could be smuggled on board Apollo 12 without its being discovered. Attempted Stunts
The Apollo 12 mission patch shows the crew's Navy background. It features a clipper ship arriving at the moon. The ship trails fire and flies the flag of the United States. The mission name APOLLO XII and the crew names are on a wide gold border, with a small blue trim. Blue and gold are traditionally Navy colors. The patch has four stars on it — one each for the three astronauts who flew the mission and one for Clifton Williams. Williams was killed on October 5, 1967, after a mechanical failure caused the controls of his T-38 trainer to stop responding. He had been assigned to the back-up crew for what would be the Apollo 9 mission and would have most likely been assigned as Lunar Module pilot for Apollo 12.
Depiction in fiction
List of spacewalks
List of artificial objects on the Moon
Posted by gigihong07 at 10:25 AM