Tag Archives: Apollo 12

Apollo 12 was the sixth manned flight in the United States Apollo program and the second to land on the Moon. It was launched on November 14, 1969, from the Kennedy Space Center, Florida, four months after Apollo 11. Commander Charles “Pete” Conrad and Lunar Module Pilot Alan L. Bean performed just over one day and seven hours of lunar surface activity while Command Module Pilot Richard F. Gordon remained in lunar orbit.

Mission Objectives

Primary objectives included:

  1. Perform inspection, survey, and sampling in lunar mare area
  2. Deploy an Apollo Lunar Surface Experiment Package (ALSEP).
  3. Develop techniques for a point landing capability
  4. Develop the capability to work in the lunar environment
  5. Obtain photographs of candidate exploration sites

Secondary objective was to the retrieve portions of the Surveyor III spacecraft which had been exposed to the lunar environment since the unmanned spacecraft soft-landed on the inner slope of a crater on April 20, 1967.

The Apollo 12 mission landed on November 19, 1969, on an area of the Ocean of Storms (Latin Oceanus Procellarum) that had been visited earlier by several unmanned missions (Luna 5, Surveyor 3, and Ranger 7).

Alan Bean on the moon during the Apollo 12 mission
Image: AS12-49-7278 (19-20 Nov. 1969) — Astronaut Alan L. Bean holds a Special Environmental Sample Container filled with lunar soil collected during the extravehicular activity (EVA) in which astronauts Charles Conrad Jr., commander, and Bean, lunar module pilot, participated. Conrad, who took this picture, is reflected in Bean’s helmet visor. Conrad and Bean descended in the Apollo 12 Lunar Module (LM) to explore the lunar surface while astronaut Richard F. Gordon Jr., command module pilot, remained with the Command and Service Modules (CSM) in lunar orbit. This is a resized image. You can see the original image at NASA.gov

Three hours after the landing and before the first extravehicular activity or, EVA, began. Richard Gordon, orbiting 69 miles up in the Yankee Clipper, was able to see both the Intrepid and Surveyor through the use of a 28-power sextant telescope. Conrad opened Intrepid’s hatch at 115 hours, 10 minutes into the mission to begin the first lunar EVA for the Apollo 12 crew. In their first lunar exploration, Conrad spent three hours, 39 minutes outside Intrepid, and Bean logged two hours, 58 minutes on the lurain. During this EVA, Conrad collected lunar surface samples and deployed both the S-band communication antenna and the solar wind experiment. Bean was assigned to mount the TV camera on a tripod. In the process of doing so, it was inadvertently pointed into the sun and ceased to function. The ALSEP instrumentation and SNAP-27 RTG were deployed within an arc of 600 to 700 feet of the LM. The ALSEP functioned satisfactorily, except for two items in the package, and was expected to yield data for up to two years. Deployment of the ALSEP took about an hour to complete. Throughout this first EVA, Conrad and Bean also took photographs of the experiment equipment, the spacecraft, the lurain and of themselves. Before entering the Intrepid, Bean took a 16-inch-deep core sample of the lunar surface and was followed back into the LM by Conrad. The first EVA ended at 119 hours, five minutes into the mission. The crew then ate, recharged their backpacks, prepared for the second EVA the following day, and slept for about five hours.

On Nov. 20, an hour and a half earlier than planned, the crew began the second EVA. Conrad left the Intrepid some 131 hours, 28 minutes into the mission. The second EVA included the collection of 70 pounds of rock and dirt samples, the retrieval of 10 to 15 pounds of randomly selected selenological samples, and further probing of two areas to retrieve lunar material from depths up to 32 inches below the surface. The crew retrieved the TV camera and stored it in the LM for the return to Earth. The most important part of this second EVA was a 5,200-foot traverse of the lurain, ranging up to 1,300 feet from Intrepid. Walking northwest to the site of the ALSEP deployment, Conrad and Bean then turned south to perform a selenological rock survey. They skirted the rim of Head Crater, walked further south past Bench Crater, west around Sharp Crater, and back east past Bench Crater again, south of Halo Crater. Eventually, they turned northeast, entering the 650-foot-wide Surveyor Crater to retrieve parts of Surveyor III, which was perched some 150 feet from the edge at the southern quadrant.

During the exploration, the astronauts discussed their findings by voice communication with geologists in Houston, who provided advice about which samples to retrieve. Surveyor was extensively photographed before parts were retrieved. The 17-pound TV camera was severed from its mount so that extensive studies could be performed on Earth of its gears, motors, optics, metals, and lubricants. This would help determine the long-term effects of exposure to the elements. Similarly, the Surveyor’s motorized scoop, and pieces of TV cable, aluminum tubing and glass were gathered. Scientists on Earth were particularly interested in the cable because biological organisms had been trapped within it, and they wanted to know if any had survived.

Conrad and Bean then walked north, climbed up a slope of about 14 degrees into Block Crater located on the rim of Surveyor Crater. They then turned west back to Intrepid, gathering surface samples as they went. They returned to the spacecraft at 134 hours, 49 minutes into the mission. Bean re-entered the LM at about 135 hours, 10 minutes, and Conrad followed at 135 hours, 22 minutes. The second EVA lasted three hours, 48 minutes. The crew removed their pressurized suits and jettisoned them on the moon before eating a meal.

Approximately six hours later on the same day, after a total of 31.6 hours on the moon, the LM ascent stage fired for about seven minutes, putting Intrepid into an initial orbit of 10 by 54 miles for rendezvous and docking with the Yankee Clipper. About three and a half hours later, the rendezvous and docking maneuvers were televised to Earth by Gordon.

Following transfer to the CSM, the ascent stage jettisoned and deorbited to impact the moon. This provided predictable impact data for the ALSEP seismometer. Although planned to impact about six miles from the ALSEP, it landed about 40 miles away. The combined length and severity of the seismic disturbance set up by the impact, estimated to equal that of one ton of TNT. To the surprise of seismologists, strong signals lasted for more than a half hour, and weaker signals ceased about an hour later. The effects were studied, as was the data received from other experiments left on the moon.

A heavy schedule of photographing future landing sites on the lunar surface occurred from the CSM, preceded by a change of plane maneuver 3.8 degrees to the north, on the 39th lunar revolution. The maneuver was performed by a 19-second burn of the service propulsion system, or SPS. Earlier, while the Yankee Clipper was in its 27th and 28th revolutions, Gordon conducted the multi-spectral photographic survey of the lunar surface. During the 45th revolution and the 89th hour of the mission, the SPS ignited to put Apollo 12 into a trans-Earth trajectory. The trajectory occurred 172 hours, 27 minutes into the mission Nov. 21.

The return flight was uneventful. A midcourse correction maneuver occurred Nov. 22, when Apollo 12 was about 208,000 miles from Earth. On Nov. 23, when the spacecraft was 108,000 miles from Earth, the crew held a televised news conference, followed by sleep. A second scheduled midcourse correction maneuver was not needed. On Nov. 24, following the same nominal re-entry procedure scheduled for Apollo 11, Apollo 12 ended its 10-day flight by splashing down in the Pacific Ocean at 15 degrees, 46.6 minutes south latitude, and 165 degrees, 9 minutes west. Splashdown occurred about three miles from the target area, and three miles south of and within sight of the recovery ship USS Hornet. The splashdown occurred about 400 miles southeast of American Samoa, after a flight of 244 hours, 36 minutes, 25 seconds – just 62 seconds longer than planned.

Sources

Why NASA Launches Rockets From Cape Canaveral, Florida?

Have you ever wondered why NASA chose Cape Canaveral to launch rockets? NASA’s most important rocket launches including the Mercury program, Project Gemini, the Moon Missions, and Space Shuttle lifted off from the Kennedy Space Center in Cape Canaveral, Florida.

In fact, at the first look, Florida doesn’t look like a convenient place for rocket launches: the southeasternmost state gets hit by lightning more than anywhere in the United States. And getting hit by lightning is a very bad thing during a rocket launch Notes 1. What’s more, monster hurricanes frequently hit Florida (almost every year).

So, why NASA chose Cape Canaveral?

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Alan Bean, the fourth person to walk on the Moon has died

Alan Bean, the fourth person to walk on the Moon has died today (May 26, 2018). He was the fourth person to walk on the Moon: in November 1969, he spent 10+ hours on the lunar surface during Apollo 12 mission, the sixth manned flight in the United States Apollo program and the second to land on the Moon.

Born March 15, 1932, in Wheeler, Texas, Bean received a Bachelor of Science degree in aeronautical engineering from the University of Texas in 1955. He attended the Navy Test Pilot School and accumulated more than 5,500 hours of flying time in 27 different types of aircraft. He was selected to become an astronaut by NASA in 1963 as part of Astronaut Group 3.

Continue reading Alan Bean, the fourth person to walk on the Moon has died