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An Apollo 1 mission patch was left on the Moon's surface after the first crewed lunar landing by Apollo11 crew members Neil Armstrong and Buzz Aldrin. The Apollo15 mission left on the surface of the Moon a tiny memorial statue, "Fallen Astronaut", along with a plaque containing the names of the Apollo1 astronauts, among others including Soviet cosmonauts, who perished in the pursuit of human space flight.
Launch Complex 34.
After the Apollo 1 fire, Launch Complex 34 was subsequently used only for the launch of Apollo7 and later dismantled down to the concrete launch pedestal, which remains at the site () along with a few other concrete and steel-reinforced structures. The pedestal bears two plaques commemorating the crew.
The "Ad Astra per aspera" plaque for "the crew of Apollo 1" is seen in the 1998 film "Armageddon".
The "Dedicated to the living memory of the crew of the Apollo 1" plaque is quoted at the end of Wayne Hale's Requiem for the NASA Space Shuttle program. Each year the families of the Apollo1 crew are invited to the site for a memorial, and the Kennedy Space Center Visitor Complex includes the site during the tour of the historic Cape Canaveral launch sites.
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In January 2005, three granite benches, built by a college classmate of one of the astronauts, were installed at the site on the southern edge of the launch pad. Each bears the name of one of the astronauts and his military service insignia.
Civic and other memorials.
Virgil Grissom Elementary School in Houston, Texas.
Remains of CM-012.
The Apollo 1 command module has never been on public display. After the accident, the spacecraft was removed and taken to Kennedy Space Center to facilitate the review board's disassembly in order to investigate the cause of the fire. When the investigation was complete, it was moved to the NASA Langley Research Center in Hampton, Virginia, and placed in a secured storage warehouse.
On February 17, 2007, the parts of CM-012 were moved approximately to a newer, environmentally controlled warehouse. Only a few weeks earlier, Gus Grissom's brother Lowell publicly suggested CM-012 be permanently entombed in the concrete remains of Launch Complex 34.
On January 27, 2017, the 50th anniversary of the fire, NASA put the hatch from Apollo1 on display at the Saturn V Rocket Center at Kennedy Space Center Visitors Complex. KSC's Visitor Complex also houses memorials that include parts of "Challenger" and "Columbia," located in the Space Shuttle "Atlantis" exhibit. "This is way, way, way long overdue. But we're excited about it," said Scott Grissom, Gus Grissom's older son.
References.
Notes
Citations
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Apollo 10
Apollo 10 (May 18–26, 1969) was the fourth human spaceflight in the United States' Apollo program and the second to orbit the Moon. NASA, the mission's operator, described it as a "dress rehearsal" for the first Moon landing (Apollo 11, two months later). It was designated an "F"mission, intended to test all spacecraft components and procedures short of actual descent and landing.
After the spacecraft reached lunar orbit, astronaut John Young remained in the Command and Service Module (CSM) while astronauts Thomas Stafford and Gene Cernan flew the Apollo Lunar Module (LM) to within (7.8 nautical miles; ) of the lunar surface, the point at which powered descent for landing would begin on a landing mission. After four orbits they rejoined Young in the CSM and, after the CSM completed its 31st orbit of the Moon, they returned safely to Earth.
While NASA had considered attempting the first crewed lunar landing on Apollo 10, mission planners ultimately decided that it would be prudent to have a practice flight to hone the procedures and techniques. The crew encountered some problems during the flight: pogo oscillations during the launch phase and a brief, uncontrolled tumble of the LM ascent stage in lunar orbit during its solo flight. However, the mission accomplished its major objectives. Stafford and Cernan observed and photographed Apollo 11's planned landing site in the Sea of Tranquility. Apollo 10 spent 61 hours and 37 minutes orbiting the Moon, for about eight hours of which Stafford and Cernan flew the LM apart from Young in the CSM, and about eight days total in space. Additionally, Apollo 10 set the record for the highest speed attained by a crewed vehicle: 39,897 kilometers per hour (11.08 kilometers per second or 24,791 miles per hour) on May 26, 1969, during the return from the Moon.
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The mission's call signs were the names of the "Peanuts" characters Charlie Brown for the CSM and Snoopy for the LM, who became Apollo 10's semi-official mascots. "Peanuts" creator Charles Schulz also drew mission-related artwork for NASA.
Framework.
Background.
By 1967, NASA had devised a list of mission types, designated by letters, that needed to be flown before a landing attempt, which would be the "G" mission. The early uncrewed flights were considered "A" or "B" missions, while Apollo 7, the crewed-flight test of the Command and Service Module (CSM), was the "C" mission. The first crewed orbital test of the Lunar Module (LM) was accomplished on Apollo 9, the "D" mission. Apollo 8, flown to the Moon's orbit without an LM, was considered a "C-prime" mission, but its success gave NASA the confidence to skip the "E" mission, which would have tested the full Apollo spacecraft in medium or high Earth orbit. Apollo 10, the dress rehearsal for the lunar landing, was to be the "F" mission.
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Crew and key Mission Control personnel.
On November 13, 1968, NASA announced the crew members of Apollo 10. Thomas P. Stafford, the commander, was 38 years old at the time of the mission. A 1952 graduate of the Naval Academy, he was commissioned in the Air Force. Selected for the second group of astronauts in 1962, he flew as pilot of Gemini 6A (1965) and command pilot of Gemini 9A (1966). John Young, the command module pilot, was 38 years old and a commander in the Navy at the time of Apollo 10. A 1952 graduate of Georgia Tech who entered the Navy after graduation and became a test pilot in 1959, he was selected as a Group 2 astronaut alongside Stafford. He flew in Gemini 3 with Gus Grissom in 1965, becoming the first American not of the Mercury Seven to fly in space. Young thereafter commanded Gemini 10 (1966), flying with Michael Collins. Gene Cernan, the lunar module pilot, was a commander in the Navy at the time of Apollo 10. A 1952 graduate of Purdue University, he entered the Navy after graduation. Selected for the third group of astronauts in 1963, Cernan flew with Stafford on Gemini 9A before his assignment to Apollo 10. With five prior flights among them, the Apollo 10 crew was the most experienced to reach space until the Space Shuttle era, and the first American space mission whose crew were all spaceflight veterans.
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The backup crew for Apollo 10 was Gordon Cooper as commander, Donn F. Eisele as command module pilot, and Edgar D. Mitchell as lunar module pilot. By the normal crew rotation in place during Apollo, Cooper, Eisele, and Mitchell would have flown on Apollo 13, but Cooper and Eisele never flew again. Deke Slayton, Director of Flight Crew Operations, felt that Cooper did not train as hard as he could have. Eisele was blackballed because of incidents during Apollo 7, which he had flown as CMP and which had seen conflict between the crew and ground controllers; he had also been involved in a messy divorce. Slayton only assigned the two as backups because he had few veteran astronauts available. Cooper and Eisele were replaced by Alan Shepard and Stuart Roosa respectively. Feeling they needed additional training time, George Mueller rejected the Apollo 13 crew. The crew was switched to Apollo 14, which saw Shepard and Mitchell walk on the Moon.
For projects Mercury and Gemini, a prime and a backup crew had been designated, but for Apollo, a third group of astronauts, known as the support crew, was also designated. Slayton created the support crews early in the Apollo program on the advice of McDivitt, who would lead Apollo 9. McDivitt believed that, with preparation going on in facilities across the U.S., meetings that needed a member of the flight crew would be missed. Support crew members were to assist as directed by the mission commander. Usually low in seniority, they assembled the mission's rules, flight plan, and checklists, and kept them updated. For Apollo 10, they were Joe Engle, James Irwin, and Charles Duke.
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Flight directors were Gerry Griffin, Glynn Lunney, Milt Windler, and Pete Frank. Flight directors during Apollo had a one-sentence job description: "The flight director may take any actions necessary for crew safety and mission success." CAPCOMs were Duke, Engle, Jack Lousma, and Bruce McCandless II.
Call signs and mission insignia.
The command module was given the call sign "Charlie Brown" and the lunar module the call sign "Snoopy". These were taken from the characters in the comic strip, "Peanuts", Charlie Brown, and Snoopy. These names were chosen by the astronauts with the approval of Charles Schulz, the strip's creator, who was uncertain it was a good idea, since Charlie Brown was always a failure. The choice of names was deemed undignified by some at NASA, as were the choices for Apollo 9's CM and LM ("Gumdrop" and "Spider"). Public relations chief Julian Scheer urged a change for the lunar landing mission. But for Apollo 10, according to Cernan, "The P.R.-types lost this one big-time, for everybody on the planet knew the klutzy kid and his adventuresome beagle, and the names were embraced in a public relations bonanza." Apollo 11's call signs were "Columbia" for the command module and "Eagle" for the lunar module.
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Snoopy, Charlie Brown's dog, was chosen for the call sign of the lunar module since it was to "snoop" around the landing site, with Charlie Brown given to the command module as Snoopy's companion. Snoopy had been associated for some time with the space program, with workers who performed in an outstanding manner awarded silver "Snoopy pins", and Snoopy posters were seen at NASA facilities, with the cartoon dog having traded in his World War I aviator's headgear for a space helmet. Stafford stated that, given the pins, "the choice of Snoopy [as call sign] was a way of acknowledging the contributions of the hundreds of thousands of people who got us there". The use of the dog was also appropriate since, in the comic strip, Snoopy had journeyed to the Moon the year before, thus defeating, according to Schulz, "the Americans, the Russians, and that stupid cat next door".
The shield-shaped mission insignia shows a large, three-dimensional Roman numeral X sitting on the Moon's surface, in Stafford's words, "to show that we had left our mark". Although it did not land on the Moon, the prominence of the number represents the contributions the mission made to the Apollo program. A CSM circles the Moon as an LM ascent stage flies up from its low pass over the lunar surface with its engine firing. The Earth is visible in the background. On the mission patch, a wide, light blue border carries the word APOLLO at the top and the crew names around the bottom. The patch is trimmed in gold. The insignia was designed by Allen Stevens of Rockwell International.
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Training and preparation.
Apollo 10, the "F" mission or dress rehearsal for the lunar landing, had as its primary objectives to demonstrate crew, space vehicle, and mission support facilities performance during a crewed mission to lunar orbit, and to evaluate the performance of the lunar module there. In addition, it was to attempt photography of Apollo Landing Site 2 (ALS-2) in the Sea of Tranquillity, the contemplated landing site for Apollo 11. According to Stafford, Our flight was to take the first lunar module to the moon. We would take the lunar module, go down to within about ten miles above the moon, nine miles above the mountains, radar map, photo map, pick out the first landing site, do the first rendezvous around the moon, pick out some future landing sites, and come home.
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The Apollo 10 astronauts undertook five hours of formal training for each hour of the mission's eight-day duration. This was in addition to the normal mission preparations such as technical briefings, pilot meetings, and study. They took part in the testing of the CSM at the Downey, California, facility of its manufacturer, North American Rockwell, and of the LM at Grumman in Bethpage, New York. They visited Cambridge, Massachusetts, for briefings on the Apollo Guidance Computer at the Massachusetts Institute of Technology Instrumentation Laboratory. They each spent more than 300 hours in simulators of the CM or LM at the Manned Spacecraft Center (MSC) in Houston and at Kennedy Space Center (KSC) in Florida. To train for the high-acceleration conditions they would experience in returning to Earth's atmosphere, they endured MSC's centrifuge.
Lunar landing capability.
While Apollo 10 was meant to follow the procedures of a lunar landing mission to the point of powered descent, Apollo 10's LM was not capable of landing and returning to lunar orbit. The ascent stage was loaded with the amount of fuel and oxidizer it would have had remaining if it had lifted off from the surface and reached the altitude at which the Apollo 10 ascent stage fired; this was only about half the total amount required for lift off and rendezvous with the CSM. The mission-loaded LM weighed , compared to for the Apollo 11 LM, which made the first landing. Additionally, the software necessary to guide the LM to a landing was not available at the time of Apollo 10.
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Craig Nelson wrote in his book "Rocket Men" that NASA took special precautions to ensure Stafford and Cernan would not attempt to make the first landing. Nelson quoted Cernan as saying "A lot of people thought about the kind of people we were: 'Don't give those guys an opportunity to land, 'cause they might!' So the ascent module, the part we lifted off the lunar surface with, was short-fueled. The fuel tanks weren't full. So had we literally tried to land on the Moon, we couldn't have gotten off." Mueller, NASA's Associate Administrator for Manned Space Flight, stated, There had been some speculation about whether or not the crew might have landed, having gotten so close. They might have wanted to, but it was impossible for that lunar module to land. It was an early design that was too heavy for a lunar landing, or, to be more precise, too heavy to be able to complete the ascent back to the command module. It was a test module, for the dress rehearsal only, and that was the way it was used.
Equipment.
The descent stage of the LM was delivered to KSC on October 11, 1968, and the ascent stage arrived five days later. They were mated on November 2. The Service Module (SM) and Command Module (CM) arrived on November 24 and were mated two days later. Portions of the Saturn V launch vehicle arrived during November and December 1968, and the complete launch vehicle was erected in the Vehicle Assembly Building (VAB) on December 30. After being tested in an altitude chamber, the CSM was placed atop the launch vehicle on February 6, 1969. The completed space vehicle was rolled out to Launch Complex 39B on March 11, 1969—the fact that it had been assembled in the VAB's High Bay 2 (the first time it had been used) required the crawler to exit the rear of the VAB before looping around the building and joining the main crawlerway, proceeding to the launch pad. This rollout, using Mobile Launch Platform-3 (MLP-3), happened eight days after the launch of Apollo 9, while that mission was still in orbit.
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The launch vehicle for Apollo 10 was a Saturn V, designated AS-505, the fifth flight-ready Saturn V to be launched and the third to take astronauts to orbit. The Saturn V differed from that used on Apollo 9 in having a lower dry weight (without propellant) in its first two stages, with a significant reduction to the interstage joining them. Although the S-IVB third stage was slightly heavier, all three stages could carry a greater weight of propellant, and the S-II second stage generated more thrust than that of Apollo 9.
The Apollo spacecraft for the Apollo 10 mission was composed of Command Module 106 (CM-106), Service Module 106 (SM-106, together with the CM known as CSM-106), Lunar Module 4 (LM-4), a spacecraft-lunar module adapter (SLA), numbered as SLA-13A, and a launch escape system. The SLA was a mating structure joining the Instrument Unit on the S-IVB stage of the Saturn V launch vehicle and the CSM, and acted as a housing for the LM, while the Launch Escape System (LES) contained rockets to propel the CM to safety if there was an aborted launch. At about 76.99 metric tons, Apollo 10 would be the heaviest spacecraft to reach orbit to that point.
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Mission highlights.
Launch and outbound trip.
Apollo 10 launched from KSC on May 18, 1969, at 16:49:00 UTC (12:49:00 EDT, local time at the launch site), at the start of a 4.5-hour launch window. The launch window was timed to secure optimal lighting conditions at Apollo Landing Site 2 at the time of the LM's closest approach to the site days later. The launch followed a countdown that had begun at 01:00:00 UTC on May 17. Because preparations for Apollo 11 had already started at LC-39A, Apollo 10 launched from LC-39B, becoming the only Apollo flight to launch from that pad and the only one to be controlled from its Firing Room 3.
Problems that arose during the countdown were dealt with during the built-in holds and did not delay the mission. On the day before launch, Cernan had been stopped for speeding while returning from a final visit with his wife and child. Lacking identification and under orders to tell no one who he was, Cernan later attested in his autobiography that he had feared being arrested. Launch pad leader Gunther Wendt, who had pulled over nearby after recognizing Cernan, explained the situation to the police officer, who then released Cernan despite the officer's skepticism that Cernan was an astronaut.
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The crew experienced a somewhat rough ride on the way to orbit due to pogo oscillations. About 12 minutes after liftoff, the spacecraft entered a low Earth orbit with a high point of (100.32 nautical miles; ) and a low point of (99.71 nautical miles; ). All appeared to be normal during the systems review period in Earth orbit, and the crew restarted the S-IVB third stage to achieve trans-lunar injection (TLI) and send them towards the Moon. The vehicle shook again while executing the TLI burn, causing Cernan to be concerned that they might have to abort. However, the TLI burn was completed without incident. Young then performed the transposition, docking, and extraction maneuver, separating the CSM from the S-IVB stage, turning around, and docking its nose to the top of the lunar module (LM), before separating from the S-IVB. Apollo 10 was the first mission to carry a color television camera inside the spacecraft, and mission controllers in Houston watched as Young performed the maneuver. Soon thereafter, the large television audience was treated to color views of the Earth. One problem that was encountered was that the mylar cover of the CM's hatch had pulled loose, spilling quantities of fiberglass insulation into the tunnel, and then into both the CM and LM. The S-IVB was fired by ground command and sent into solar orbit with a period of 344.88 days.
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The crew settled in for the voyage to the Moon. They had a light workload, and spent much of their time studying the flight plan or sleeping. They made five more television broadcasts back to Earth, and were informed that more than a billion people had watched some part of their activities. In June 1969, the crew would accept a special Emmy Award on behalf of the first four Apollo crews for their television broadcasts from space. One slight course correction was necessary; this occurred at 26:32:56.8 into the mission and lasted 7.1 seconds. This aligned Apollo 10 with the trajectory Apollo 11 was expected to take. One issue the crew encountered was bad-tasting food, as Stafford apparently used a double dose of chlorine in their drinking water, which had to be placed in their dehydrated food to reconstitute it.
Lunar orbit.
Arrival and initial operations.
At 75:55:54 into the mission, (95.1 nautical miles; ) above the far side of the Moon, the CSM's service propulsion system (SPS) engine was fired for 356.1 seconds to slow the spacecraft into a lunar orbit of (170 by 60.2 nautical miles; ). This was followed, after two orbits of the Moon, with a 13.9-second firing of the SPS to circularize the orbit to (61 by 59.2 nautical miles; ) at 80:25:08.1. Within the first couple of hours after the initial lunar orbit insertion burn and following the circularization burn, the crew turned to tracking planned landmarks on the surface below to record observations and take photographs. In addition to ALS-1, ALS-2, and ALS-3, the crew of Apollo 10 observed and photographed features on the near and far sides of the Moon, including the craters Coriolis, King, and Papaleksi. Shortly after the circularization burn, the crew partook in a scheduled half-hour color-television broadcast with descriptions and video transmissions of views of the lunar surface below.
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About an hour after the second burn, the LM crew of Stafford and Cernan entered the LM to check out its systems. They were met with a blizzard of fiberglass particles from the earlier problem, which they cleaned up with a vacuum cleaner as best they could. Stafford had to help Cernan remove smaller bits from his hair and eyebrows. Stafford later commented that Cernan looked like he just came out of a chicken coop, and that the particles made them itch and got into the air conditioning system, and they were scraping it off the filter screens for the rest of the mission. This was merely an annoyance, but the particles may have gotten into the docking ring joining the two craft and caused it to misalign slightly. Mission Control determined that this was still within safe limits.
The flight of "Snoopy".
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The next action was to prepare to separate the LM ascent stage from the descent stage, to jettison the descent stage, and fire the Ascent Propulsion System to return the ascent stage towards the CSM. As Stafford and Cernan prepared to do so, the LM began to gyrate out of control. Alarmed, Cernan exclaimed, "Son of a bitch!" into a hot mic being broadcast live, which, combined with other language used by the crew during the mission, generated some complaints back on Earth. Stafford discarded the descent stage about five seconds after the tumbling began and fought to regain control manually, suspecting that there might have been an "open thruster", or a thruster stuck firing. He did so in time to orient the spacecraft to rejoin "Charlie Brown". The problem was traced to a switch controlling the mode of the abort guidance system; it was to be moved as part of the procedure, but both of the crew members switched it, thus returning it to the original position. Had they fired "Snoopy" in the wrong direction, they might have missed the rendezvous with "Charlie Brown" or crashed into the Moon. Once Stafford had regained control of the LM ascent stage, which took about eight seconds, the pair fired the ascent engine at the lowest point of the LM's orbit, mimicking the orbital insertion maneuver after launch from the lunar surface in a later landing mission. "Snoopy" coasted on that trajectory for about an hour before firing the engine once more to further fine-tune its approach to "Charlie Brown".
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"Snoopy" rendezvoused with and re-docked with "Charlie Brown" at 106:22:02, just under eight hours after undocking. The docking was telecast live in color from the CSM. Once Cernan and Stafford had re-entered "Charlie Brown", "Snoopy" was sealed off and separated from "Charlie Brown." The rest of the LM's ascent-stage engine fuel was burned to send it on a trajectory past the Moon and into a heliocentric orbit.
It was the only Apollo LM to meet this fate. The Apollo 11 ascent stage would be left in lunar orbit to crash randomly, while ascent stages of later Apollo mission (12, 14, 15 and 17) were steered into the Moon to obtain readings from seismometers placed nearby on the surface, with two exceptions: Apollo 13's ascent stage, which the crew used as a "life boat" to get safely back to Earth before releasing it to burn up in Earth's atmosphere, and Apollo 16's, which NASA lost control of after jettison.
Return to Earth.
After ejecting the LM ascent stage, the crew slept and performed photography and observation of the lunar surface from orbit. Though the crew located 18 landmarks on the surface and took photographs of various surface features, crew fatigue necessitated the cancellation of two scheduled television broadcasts. Thereafter, the main Service Propulsion System engine of the CSM re-ignited for about 2.5 minutes to set Apollo 10 on a trajectory towards Earth, achieving such a trajectory at 137:39:13.7. As it departed lunar orbit, Apollo 10 had orbited the Moon 31 times over the span of about 61 hours and 37 minutes.
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During their journey back to Earth, the crew performed some observational activities which included star-Earth horizon sightings for navigation. The crew also performed a scheduled test to gauge the reflectivity of the CSM's high-gain antenna and broadcast six television transmissions of varying durations to show views inside the spacecraft and of the Earth and Moon from the crew's vantage point. Cernan reported later that he and his crewmates became the first to "successfully shave in space" during the return trip, using a safety razor and thick shaving gel, as such items had been deemed a safety hazard and prohibited on earlier flights. The crew fired the engine of the CSM for the only mid-course-correction burn required during the return trip at 188:49:58, a few hours before separation of the CM from the SM. The burn lasted about 6.7 seconds.
As the spacecraft rapidly approached Earth on the final day of the mission, the Apollo 10 crew traveled faster than any humans before or since, relative to Earth: 39,897 km/h (11.08 km/s or 24,791 mph). This is because the return trajectory was designed to take only 42 hours rather than the normal 56. The Apollo 10 crew also traveled farther than any humans before or since from their (Houston) homes: (408,950 nautical miles; ) (though the Apollo 13 crew was 200 km farther away from Earth as a whole).
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At 191:33:26, the CM (which contained the crew) separated from the SM in preparation for reentry, which occurred about 15 minutes later at 191:48:54.5. Splashdown of the CM occurred about 15 minutes after reentry in the Pacific Ocean about (400 nautical miles; ) east of American Samoa on May 26, 1969, at 16:52:23 UTC and mission elapsed time 192:03:23. The astronauts were recovered by . They spent about four hours aboard, during which they took a congratulatory phone call from President Richard Nixon. As they had not made contact with the lunar surface, Apollo 10's crew were not required to quarantine like the first landing crews would be. They were flown to Pago Pago International Airport in Tafuna for a greeting reception, before boarding a C-141 cargo plane to Ellington Air Force Base near Houston.
Aftermath.
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In July 1969, Stafford replaced Alan Shepard as Chief Astronaut, and then became deputy director of Flight Crew Operations under Deke Slayton. In his memoirs, Stafford wrote that he could have put his name back in the flight rotation, but wanted managerial experience. In 1972, Stafford was promoted to brigadier general and assigned to command the American portion of the Apollo–Soyuz Test Project, which flew in July 1975. He commanded the Air Force Flight Test Center at Edwards Air Force Base in California, and retired in November 1979 as a lieutenant general. Young commanded the Apollo 16 lunar landing mission flown in April 1972. From 1974 to 1987, Young served as Chief Astronaut, commanding the STS-1 (1981) and STS-9 (1983) Space Shuttle missions in April 1981 and November 1983, respectively, and retired from NASA's Astronaut Corps in 2004. Gene Cernan commanded the final Apollo lunar mission, Apollo 17, flown in December 1972. Cernan retired from NASA and the Navy as a captain in 1976.
Hardware disposition.
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The Smithsonian has been accountable for the command module "Charlie Brown" since 1970. The spacecraft was on display in several countries until it was placed on loan to the London Science Museum in 1978. "Charlie Brown"'s SM was jettisoned just before re-entry and burned up in the Earth's atmosphere, its remnants scattering in the Pacific Ocean.
After translunar injection, the Saturn V's S-IVB third stage was accelerated past Earth escape velocity to become space debris; , it remains in a heliocentric orbit.
The ascent stage of the Lunar Module "Snoopy" was jettisoned into a heliocentric orbit. "Snoopy"'s ascent stage orbit was not tracked after 1969, and its whereabouts were unknown. In 2011, a group of amateur astronomers in the UK started a project to search for it. In June 2019, the Royal Astronomical Society announced a possible rediscovery of "Snoopy", determining that small Earth-crossing asteroid 2018 AV2 is likely to be the spacecraft with "98%" certainty. It is the only once-crewed spacecraft known to still be in outer space without a crew.
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"Snoopy's" descent stage was jettisoned in lunar orbit; its current location is unknown, though it may have eventually crashed into the Moon as a result of orbital decay. Phil Stooke, a planetary scientist who studied the lunar crash sites of the LM's ascent stages, wrote that the descent stage "crashed at an unknown location", and another source stated that the descent stage "eventually impact(ed) within a few degrees of the equator on the near side". Richard Orloff and David M. Harland, in their sourcebook on Apollo, stated that "the descent stage was left in the low orbit, but perturbations by 'mascons' would have caused this to decay, sending the stage to crash onto the lunar surface".
External links.
NASA reports
Multimedia
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Apollo 12
Apollo 12 (November 14–24, 1969) was the sixth crewed flight in the United States Apollo program and the second to land on the Moon. It was launched on November 14, 1969, by NASA from the Kennedy Space Center in Florida. Commander Charles "Pete" Conrad and Lunar Module Pilot Alan L. Bean completed just over one day and seven hours of lunar surface activity while Command Module Pilot Richard F. Gordon remained in lunar orbit.
Apollo 12 would have attempted the first lunar landing had Apollo 11 failed, but after the success of the earlier mission, Apollo 12 was postponed by two months, and other Apollo missions also put on a more relaxed schedule. More time was allotted for geologic training in preparation for Apollo 12 than for Apollo 11, Conrad and Bean making several geology field trips in preparation for their mission. Apollo 12's spacecraft and launch vehicle were almost identical to Apollo 11's. One addition was a set of hammocks, designed to provide Conrad and Bean with a more comfortable resting arrangement inside the Lunar Module during their stay on the Moon.
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Shortly after being launched on a rainy day at Kennedy Space Center, Apollo 12 was twice struck by lightning, causing instrumentation problems but little damage. The crew found that switching to the auxiliary power supply resolved the data relay problem, which helped save the mission. The outward journey to the Moon otherwise saw few problems. On November 19, Conrad and Bean achieved a precise landing at their expected location within walking distance of the Surveyor 3 robotic probe, which had landed on April 20, 1967. In making a pinpoint landing, they showed that NASA could plan future missions in the expectation that astronauts could land close to sites of scientific interest. Conrad and Bean carried the Apollo Lunar Surface Experiments Package, a group of nuclear-powered scientific instruments, as well as the first color television camera taken by an Apollo mission to the lunar surface, but transmission was lost after Bean accidentally pointed the camera at the Sun and its sensor was burned out. On the second of two moonwalks, they visited Surveyor 3 and removed parts for return to Earth.
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Lunar Module "Intrepid" lifted off from the Moon on November 20 and docked with the command module, which subsequently traveled back to Earth. The Apollo 12 mission ended on November 24 with a splashdown.
Crew and key Mission Control personnel.
The commander of the all-Navy Apollo 12 crew was Charles "Pete" Conrad, who was 39 years old at the time of the mission. After receiving a bachelor's degree in aeronautical engineering from Princeton University in 1953, he became a naval aviator, and completed United States Naval Test Pilot School at Patuxent River Naval Air Station. He was selected in the second group of astronauts in 1962, and flew on Gemini 5 in 1965, and as command pilot of Gemini 11 in 1966. Command Module Pilot Richard "Dick" Gordon, 40 years old at the time of Apollo 12, also became a naval aviator in 1953, following graduation from the University of Washington with a degree in chemistry, and completed test pilot school at Patuxent River. Selected as a Group 3 astronaut in 1963, he flew with Conrad on Gemini 11.
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The original Lunar Module pilot assigned to work with Conrad was Clifton C. Williams Jr., who was killed in October 1967 when the T-38 he was flying crashed near Tallahassee. When forming his crew, Conrad had wanted Alan L. Bean, a former student of his at the test pilot school, but had been told by Director of Flight Crew Operations Deke Slayton that Bean was unavailable due to an assignment to the Apollo Applications Program. After Williams's death, Conrad asked for Bean again, and this time Slayton yielded. Bean, 37 years old when the mission flew, had graduated from the University of Texas in 1955 with a degree in aeronautical engineering. Also a naval aviator, he was selected alongside Gordon in 1963, and first flew in space on Apollo 12. The three Apollo 12 crew members had backed up Apollo 9 earlier in 1969.
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Preparation.
Site selection.
The landing site selection process for Apollo 12 was greatly informed by the site selection for Apollo 11. There were rigid standards for the possible Apollo 11 landing sites, in which scientific interest was not a major factor: they had to be close to the lunar equator and not on the periphery of the portion of the lunar surface visible from Earth; they had to be relatively flat and without major obstructions along the path the Lunar Module (LM) would fly to reach them, their suitability confirmed by photographs from Lunar Orbiter probes. Also desirable was the presence of another suitable site further west in case the mission was delayed, and the Sun would have risen too high in the sky at the original site for desired lighting conditions. The need for three days to recycle if a launch had to be scrubbed meant that only three of the five suitable sites found were designated as potential landing sites for Apollo 11, of which the Apollo 11 landing site in the Sea of Tranquility was the easternmost. Since Apollo 12 was to attempt the first lunar landing if Apollo 11 failed, both sets of astronauts trained for the same sites.
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With the success of Apollo 11, it was initially contemplated that Apollo 12 would land at the site next further west from the Sea of Tranquility, in Sinus Medii. However, NASA planning coordinator Jack Sevier and engineers at the Manned Spaceflight Center at Houston argued for a landing close enough to the crater in which the Surveyor 3 probe had landed in 1967 to allow the astronauts to cut parts from it for return to Earth. The site was otherwise suitable and had scientific interest. Given that Apollo 11 had landed several miles off-target, though, some NASA administrators feared Apollo 12 would land far enough away that the astronauts could not reach the probe, and the agency would be embarrassed. Nevertheless, the ability to perform pinpoint landings was essential if Apollo's exploration program was to be carried out, and on July 25, 1969, Apollo Program Manager Samuel Phillips designated what became known as Surveyor crater as the landing site, despite the unanimous opposition of members of two site selection boards.
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To locate Surveyor 3, NASA invited Ewen Whitaker, who together with Gerard Kuiper worked on multiple Moon atlases. Whitaker had found the Surveyor 1 landing site with better precision than NASA. By studying images from Surveyor 3 and comparing them with photographs of thousands of similar craters under the microscope, he identified two rocks near Surveyor 3, that led to the identification of the probe's location.
Training and preparation.
The Apollo 12 astronauts spent five hours in mission-specific training for every hour they expected to spend in flight on the mission, a total exceeding 1,000 hours per crew member. Conrad and Bean received more mission-specific training than Apollo 11's Neil Armstrong and Buzz Aldrin had. This was in addition to the 1,500 hours of training they received as backup crew members for Apollo 9. The Apollo 12 training included over 400 hours per crew member in simulators of the Command Module (CM) and of the LM. Some of the simulations were linked in real time to flight controllers in Mission Control. To practice landing on the Moon, Conrad flew the Lunar Landing Training Vehicle (LLTV), training in which continued to be authorized even though Armstrong had been forced to bail out of a similar vehicle in 1968, just before it crashed.
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Soon after being assigned as Apollo 12 crew commander, Conrad met with NASA geologists and told them that the training for lunar surface activities would be conducted much as Apollo 11's, but there was to be no publicity or involvement by the media. Conrad felt he had been abused by the press during Gemini, and the sole Apollo 11 geology field trip had turned into a near-fiasco, with a large media contingent present, some getting in the way—the astronauts had trouble hearing each other due to a hovering press helicopter. After the return of Apollo 11 in July 1969, more time was allotted for geology, but the astronauts' focus was on getting time in the simulators without being preempted by the Apollo 11 crew. On the six Apollo 12 geology field trips, the astronauts would practice as if on the Moon, collecting samples and documenting them with photographs, while communicating with a CAPCOM and geologists who were out of sight in a nearby tent. Afterwards, the astronauts' performance in choosing samples and taking photographs would be critiqued. To the frustration of the astronauts, the scientists kept changing the photo documentation procedures; after the fourth or fifth such change, Conrad required that there be no more. After the return of Apollo 11, the Apollo 12 crew was able to view the lunar samples, and be briefed on them by scientists.
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As Apollo 11 was targeted for an ellipse-shaped landing zone, rather than at a specific point, there was no planning for geology traverses, the designated tasks to be done at sites of the crew's choosing. For Apollo 12, before the mission, some of NASA's geology team met with the crew and Conrad suggested they lay out possible routes for him and Bean. The result was four traverses, based on four potential landing points for the LM. This was the start of geology traverse planning that on later missions became a considerable effort involving several organizations.
The stages of the lunar module, LM–6, were delivered to Kennedy Space Center (KSC) on March 24, 1969, and were mated to each other on April 28. Command module CM–108 and service module SM–108 were delivered to KSC on March 28, and were mated to each other on April 21. Following installation of gear and testing, the launch vehicle, with the spacecraft atop it, was rolled out to Launch Complex 39A on September 8, 1969. The training schedule was complete, as planned, by November 1, 1969; activities after that date were intended as refreshers. The crew members felt that the training, for the most part, was adequate preparation for the Moon mission.
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Hardware.
Launch vehicle.
There were no significant changes to the Saturn V launch vehicle used on Apollo 12, SA–507, from that used on Apollo 11. There were another 17 instrumentation measurements in the Apollo 12 launch vehicle, bringing the number to 1,365. The entire vehicle, including the spacecraft, weighed at launch, an increase from Apollo 11's . Of this figure, the spacecraft weighed , up from on Apollo 11.
Third stage trajectory.
After LM separation, the third stage of the Saturn V, the S-IVB, was intended to fly into solar orbit. The S-IVB auxiliary propulsion system was fired, with the intent that the Moon's gravity would slingshot the stage into solar orbit. Due to an error, the S-IVB flew past the Moon at too high an altitude to achieve Earth escape velocity. It remained in a semi-stable Earth orbit until it finally escaped Earth orbit in 1971, but briefly returned to Earth orbit 31 years later. It was discovered by amateur astronomer Bill Yeung who gave it the temporary designation J002E3 before it was determined to be an artificial object. Again in solar orbit as of 2021, it may again be captured by Earth's gravity, but not at least until the 2040s. The S-IVBs used on later lunar missions were deliberately crashed into the Moon to create seismic events that would register on the seismometers left on the Moon and provide data about the Moon's structure.
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Spacecraft.
The Apollo 12 spacecraft consisted of Command Module 108 and Service Module 108 (together Command and Service Modules 108, or CSM–108), Lunar Module 6 (LM–6), a Launch Escape System (LES), and Spacecraft-Lunar Module Adapter 15 (SLA–15). The LES contained three rocket motors to propel the CM to safety in the event of an abort shortly after launch, while the SLA housed the LM and provided a structural connection between the Saturn V and the LM. The SLA was identical to Apollo 11's, while the LES differed only in the installation of a more reliable motor igniter.
The CSM was given the call sign "Yankee Clipper", while the LM had the call sign "Intrepid". These sea-related names were selected by the all-Navy crew from several thousand proposed names submitted by employees of the prime contractors of the respective modules. George Glacken, a flight test engineer at North American Aviation, builder of the CSM, proposed "Yankee Clipper" as such ships had "majestically sailed the high seas with pride and prestige for a new America". "Intrepid" was from a suggestion by Robert Lambert, a planner at Grumman, builder of the LM, as evocative of "this nation's resolute determination for continued exploration of space, stressing our astronauts' fortitude and endurance of hardship".
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The differences between the CSM and LM of Apollo 11, and those of Apollo 12, were few and minor. A hydrogen separator was added to the CSM to stop the gas from entering the potable water tank—Apollo 11 had had one, though mounted on the water dispenser in the CM's cabin. Gaseous hydrogen in the water had given the Apollo 11 crew severe flatulence. Other changes included the strengthening of the recovery loop attached following splashdown, meaning that the swimmers recovering the CM would not have to attach an auxiliary loop. LM changes included a structural modification so that scientific experiment packages could be carried for deployment on the lunar surface. Two hammocks were added for greater comfort of the astronauts while resting on the Moon, and a color television camera substituted for the black and white one used on the lunar surface during Apollo 11.
ALSEP.
The Apollo Lunar Surface Experiments Package (ALSEP) was a suite of scientific instruments designed to be emplaced on the lunar surface by the Apollo astronauts, and thereafter operate autonomously, sending data to Earth. Development of the ALSEP was part of NASA's response to some scientists who opposed the crewed lunar landing program (they felt that robotic craft could explore the Moon more cheaply) by demonstrating that some tasks, such as deployment of the ALSEP, required humans. In 1966, a contract to design and build the ALSEPs was awarded to the Bendix Corporation. Due to the limited time the Apollo 11 crew would have on the lunar surface, a smaller suite of experiments was flown, known as the Early Apollo Surface Experiment Package (EASEP). Apollo 12 was the first mission to carry an ALSEP; one would be flown on each of the subsequent lunar landing missions, though the components that were included would vary. Apollo 12's ALSEP was to be deployed at least away from the LM to protect the instruments from the debris that would be generated when the ascent stage of the LM took off to return the astronauts to lunar orbit.
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Apollo 12's ALSEP included a Lunar Surface Magnetometer (LSM), to measure the magnetic field at the Moon's surface, a Lunar Atmosphere Detector (LAD, also known as the Cold Cathode Gauge Experiment), intended to measure the density and temperature of the thin lunar atmosphere and how it varies, a Lunar Ionosphere Detector (LID, also known as the Suprathermal Ion Detector Experiment, or SIDE), intended to study the charged particles in the lunar atmosphere, and the Solar Wind Spectrometer, to measure the strength and direction of the solar wind at the Moon's surface—the free-standing Solar Wind Composition Experiment, to measure what makes up the solar wind, would be deployed and then brought back to Earth by the astronauts. A Dust Detector was used to measure the accumulation of lunar dust on the equipment. Apollo 12's Passive Seismic Experiment (PSE), a seismometer, would measure moonquakes and other movements in the Moon's crust, and would be calibrated by the nearby planned impact of the ascent stage of Apollo 12's LM, an object of known mass and velocity hitting the Moon at a known location, and projected to be equivalent to the explosive force of one ton of TNT.
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The ALSEP experiments left on the Moon by Apollo 12 were connected to a Central Station, which contained a transmitter, receiver, timer, data processor, and equipment for power distribution and control of the experiments. The equipment was powered by SNAP-27, a radioisotope thermoelectric generator (RTG) 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—some NASA and military satellites had previously used similar systems. The plutonium core was brought from Earth in a cask attached to an LM landing leg, a container designed to survive re-entry in the event of an aborted mission, something NASA considered unlikely. The cask would survive re-entry on Apollo 13, sinking in the Tonga Trench of the Pacific Ocean, apparently without radioactive leakage.
The Apollo 12 ALSEP experiments were activated from Earth on November 19, 1969. The LAD returned only a small amount of useful data due to the failure of its power supply soon after activation. The LSM was deactivated on June 14, 1974, as was the other LSM deployed on the Moon, from Apollo 15. All powered ALSEP experiments that remained active were deactivated on September 30, 1977, principally because of budgetary constraints.
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Mission highlights.
Launch.
With President Richard Nixon in attendance, the first time a current U.S. president had witnessed a crewed space launch, as well as Vice President Spiro Agnew, Apollo 12 launched as planned on November 14, 1969 from the Kennedy Space Center at 16:22:00 UTC (11:22 am EST, local time at the launch site). This was at the start of a launch window of three hours and four minutes to reach the Moon with optimal lighting conditions at the planned landing point. There were completely overcast rainy skies, and the vehicle encountered winds of during ascent, the strongest of any Apollo mission. There was a NASA rule against launching into a cumulonimbus cloud; this had been waived and it was later determined that the launch vehicle never entered such a cloud. Had the mission been postponed, it could have been launched on November 16 with landing at a backup site where there would be no Surveyor, but since time pressure to achieve a lunar landing had been removed by Apollo 11's success, NASA might have waited until December for the next opportunity to go to the Surveyor crater.
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Lightning struck the Saturn V 36.5 seconds after lift-off, triggered by the vehicle itself. The static discharge caused a voltage transient that knocked all three fuel cells offline, meaning the spacecraft was being powered entirely from its batteries, which could not supply enough current to meet demand. A second strike at 52 seconds knocked out the "8-ball" attitude indicator. The telemetry stream at Mission Control was 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 CSM. The astronauts unexpectedly had a board red with caution and warning lights, but could not tell exactly what was wrong.
The Electrical, Environmental and Consumables Manager (EECOM) in Mission Control, John Aaron, remembered the telemetry failure pattern from an earlier test when a power loss caused a malfunction in the CSM signal conditioning electronics (SCE), which converted raw signals from instrumentation to data that could be displayed on Mission Control's consoles, and knew how to fix it. Aaron made a call, "Flight, EECOM. Try SCE to Aux", to switch the SCE to a backup power supply. The switch was fairly obscure, and neither Flight Director Gerald Griffin, CAPCOM Gerald P. Carr, nor Conrad knew what it was; Bean, who as LMP was the spacecraft's engineer, knew where to find it and threw the switch, after which 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.
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Initially, it was feared that the lightning strike could have damaged the explosive bolts that opened the Command Module's parachute compartment. The decision was made not to share this with the astronauts and to continue with the flight plan, since they would die if the parachutes failed to deploy, whether following an Earth-orbit abort or upon a return from the Moon, so nothing was to be gained by aborting. The parachutes deployed and functioned normally at the end of the mission.
Outward journey.
After systems checks in Earth orbit, performed with great care because of the lightning strikes, the trans-lunar injection burn, made with the S-IVB, took place at 02:47:22.80 into the mission, setting Apollo 12 on course for the Moon. An hour and twenty minutes later, the CSM separated from the S-IVB, after which Gordon performed the transposition, docking, and extraction maneuver to dock with the LM and separate the combined craft from the S-IVB, which was then sent on an attempt to reach solar orbit. The stage fired its engines to leave the vicinity of the spacecraft, a change from Apollo 11, where the SM's Service Propulsion System (SPS) engine was used to distance it from the S-IVB.
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As there were concerns the LM might have been damaged by the lightning strikes, Conrad and Bean entered it on the first day of flight to check its status, earlier than planned. They found no issues. At 30:52.44.36, the only necessary midcourse correction during the translunar coast was made, placing the craft on a hybrid, non-free-return trajectory. Previous crewed missions to lunar orbit had taken a free-return trajectory, allowing an easy return to Earth if the craft's engines did not fire to enter lunar orbit. Apollo 12 was the first crewed spacecraft to take a hybrid free-return trajectory, that would require another burn to return to Earth, but one that could be executed by the LM's Descent Propulsion System (DPS) if the SPS failed. The use of a hybrid trajectory allowed more flexibility in mission planning. It for example allowed Apollo 12 to launch in daylight and reach the planned landing spot on schedule. Use of a hybrid trajectory meant that Apollo 12 took 8 hours longer to go from trans-lunar injection to lunar orbit.
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Lunar orbit and Moon landing.
Apollo 12 entered a lunar orbit of with an SPS burn of 352.25 seconds at mission time 83:25:26.36. On the first lunar orbit, there was a television transmission that resulted in good-quality video of the lunar surface. On the third lunar orbit, there was another burn to circularize the craft's orbit to , and on the next revolution, preparations began for the lunar landing. The CSM and LM undocked at 107:54:02.3; a half hour later there was a burn by the CSM to separate them. The 14.4 second burn by some of the CSM's thrusters meant that the two craft would be apart when the LM began the burn to move to a lower orbit in preparation for landing on the Moon.
The LM's Descent Propulsion System began a 29-second burn at 109:23:39.9 to move the craft to the lower orbit, from which the 717-second powered descent to the lunar surface began at 110:20:38.1. Conrad had trained to expect a pattern of craters known as "the Snowman" to be visible when the craft underwent "pitchover", with the Surveyor crater in its center, but had feared he would see nothing recognizable. He was astonished to see the Snowman right where it should be, meaning they were directly on course. He took over manual control, planning to land the LM, as he had in simulations, in an area near the Surveyor crater that had been dubbed "Pete's Parking Lot", but found it rougher than expected. He had to maneuver, and landed the LM
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at 110:32:36.2 (06:54:36 UTC on November 19, 1969), just from the Surveyor probe. This achieved one objective of the mission, to perform a precision landing near the Surveyor craft.
The lunar coordinates of the landing site were 3.01239° S latitude, 23.42157° W longitude. The landing caused high velocity sandblasting of the Surveyor probe. It was later determined that the sandblasting removed more dust than it delivered onto the Surveyor, because the probe was covered by a thin layer that gave it a tan hue as observed by the astronauts, and every portion of the surface exposed to the direct sandblasting was lightened back toward the original white color through the removal of lunar dust.
Lunar surface activities.
When Conrad, the shortest man of the initial groups of astronauts, stepped onto the lunar surface his first words were "Whoopie! Man, that may have been a small one for Neil, but that's a long one for me." This was not an off-the-cuff remark: Conrad had made a bet with reporter Oriana Fallaci he would say these words, after she had queried whether NASA had instructed Neil Armstrong what to say as he stepped onto the Moon. Conrad later said he was never able to collect the money.
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To improve the quality of television pictures from the Moon, a color camera was carried on Apollo 12 (unlike the monochrome camera on Apollo 11). When Bean carried the 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 (SEC) tube. Television coverage of this mission was thus terminated almost immediately.
After raising a U.S. flag on the Moon, Conrad and Bean devoted much of the remainder of the first EVA to deploying the Apollo Lunar Surface Experiments Package (ALSEP). There were minor difficulties with the deployment. Bean had trouble extracting the RTG's plutonium fuel element from its protective cask, and the astronauts had to resort to the use of a hammer to hit the cask and dislodge the fuel element. Some of the ALSEP packages proved hard to deploy, though the astronauts were successful in all cases. With the PSE able to detect their footprints as they headed back to the LM, the astronauts secured a core tube full of lunar material, and collected other samples. The first EVA lasted 3 hours, 56 minutes and 3 seconds.
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Four possible geologic traverses had been planned, the variable being where the LM might set down. Conrad had landed it between two of these potential landing points, and during the first EVA and the rest break that followed, 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, and when the astronauts emerged from the LM some 13 hours after ending the first EVA, the first stop was Head crater, some from the LM. There, Bean noticed that Conrad's footprints showed lighter material underneath, indicating the presence of ejecta from Copernicus crater, to the north, something that scientists examining overhead photographs of the site had hoped to find. After the mission, samples from Head allowed geologists to date the impact that formed Copernicus—according to initial dating, some 810,000,000 years ago.
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Lunar orbit solo activities.
After the LM's departure, Gordon had little to say as Mission Control focused on the lunar landing. Once that was accomplished, Gordon sent his congratulations and, on the next orbit, was able to spot both the LM and the Surveyor on the ground and convey their locations to Houston. During the first EVA, Gordon prepared for a plane change maneuver, a burn to alter the CSM's orbit to compensate for the rotation of the Moon, though at times he had difficulty communicating with Houston since Conrad and Bean were using the same communications circuit. Once the two moonwalkers had returned to the LM, Gordon executed the burn, which ensured he would be in the proper position to rendezvous with the LM when it launched from the Moon.
While alone in orbit, Gordon performed the Lunar Multispectral Photography Experiment, using four Hasselblad cameras arranged in a ring and aimed through one of the CM's windows. With each camera having a different color filter, simultaneous photos would be taken by each, showing the appearance of lunar features at different points on the spectrum. Analysis of the images might reveal colors not visible to the naked eye or detectable with ordinary color film, and information could be obtained about the composition of sites that would not soon be visited by humans. Among the sites studied were contemplated landing points for future Apollo missions.
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Return.
LM "Intrepid" lifted off from the Moon at mission time 143:03:47.78, or 14:25:47 UTC on November 20, 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 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.
The crew stayed another day in lunar orbit taking photographs of the surface, including of candidate sites for future Apollo landings. A second plane change maneuver was made at 159:04:45.47, lasting 19.25 seconds.
The trans-Earth injection burn, to send the CSM "Yankee Clipper" towards home, was conducted at 172:27:16.81 and lasted 130.32 seconds. Two short midcourse correction burns were made en route. A final television broadcast was made, the astronauts answering questions submitted by the media. There was ample time for rest on the way back to Earth. 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.
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Splashdown.
"Yankee Clipper" returned to Earth on November 24, 1969 splashing down in the South Pacific Ocean southeast of Samoa at 244:36:25 (20:58:24 UTC, 10:58:24amHST, local time at the landing site). The landing was hard, resulting in a camera becoming dislodged and striking Bean in the forehead. After recovery by , they entered the Mobile Quarantine Facility (MQF), while lunar samples and Surveyor parts were sent ahead by air to the Lunar Receiving Laboratory (LRL) 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 where it was taken to the LRL, where the astronauts remained until released from quarantine on December 10.
Mission insignia.
The Apollo 12 mission patch shows the crew's naval background; all three astronauts at the time of the mission were U.S. Navy commanders. It features a clipper ship arriving at the Moon, representing the CM "Yankee Clipper". 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 traditional U.S. Navy colors. The patch has four stars on it – one each for the three astronauts who flew the mission and one for Clifton Williams, the original LMP on Conrad's crew who was killed in 1967 and would have flown the mission. The star was placed there at the suggestion of his replacement, Bean.
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The insignia was designed by the crew with the aid of several employees of NASA contractors. The Apollo 12 landing area on the Moon is within the portion of the lunar surface shown on the insignia, based on a photograph of a globe of the Moon, taken by engineers. The clipper ship was based on photographs of such a ship obtained by Bean.
Aftermath and spacecraft location.
After the mission, 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—Conrad commanded Skylab 2, the first crewed mission to the space station, while 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 was then placed at NASA's Langley Research Center in Hampton, Virginia; ownership was transferred to the Smithsonian in July 1971. It is on display at the Virginia Air and Space Center in Hampton.
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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, but the lack of tracking data confirming this caused it to conclude it most likely burned up in the atmosphere at the time of CM re-entry. The S-IVB is in a solar orbit that is sometimes affected by the Earth.
The ascent stage of LM "Intrepid" impacted the Moon November 20, 1969, at 22:17:17.7 UT (5:17pm EST). In 2009, the Lunar Reconnaissance Orbiter (LRO) photographed the Apollo 12 landing site, where the descent stage, ALSEP, Surveyor3 spacecraft, and astronaut footpaths remain. In 2011, the LRO returned to the landing site at a lower altitude to take higher resolution photographs.
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Apollo 14
Apollo 14 (January 31February 9, 1971) was the eighth crewed mission in the United States Apollo program, the third to land on the Moon, and the first to land in the lunar highlands. It was the last of the "H missions", landings at specific sites of scientific interest on the Moon for two-day stays with two lunar extravehicular activities (EVAs or moonwalks).
The mission was originally scheduled for 1970, but was postponed because of the investigation following the failure of Apollo 13 to reach the Moon's surface, and the need for modifications to the spacecraft as a result. Commander Alan Shepard, Command Module Pilot Stuart Roosa, and Lunar Module Pilot Edgar Mitchell launched on their nine-day mission on Sunday, January 31, 1971, at 4:03:02 p.m. EST. En route to the lunar landing, the crew overcame malfunctions that might have resulted in a second consecutive aborted mission, and possibly, the premature end of the Apollo program.
Shepard and Mitchell made their lunar landing on February 5 in the Fra Mauro formation – originally the target of Apollo 13. During the two walks on the surface, they collected of Moon rocks and deployed several scientific experiments. To the dismay of some geologists, Shepard and Mitchell did not reach the rim of Cone crater as had been planned, though they came close. In Apollo 14's most famous event, Shepard hit two golf balls he had brought with him with a makeshift club.
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While Shepard and Mitchell were on the surface, Roosa remained in lunar orbit aboard the Command and Service Module, performing scientific experiments and photographing the Moon, including the landing site of the future Apollo 16 mission. He took several hundred seeds on the mission, many of which were germinated on return, resulting in the so-called Moon trees, that were widely distributed in the following years. After liftoff from the lunar surface and a successful docking, the spacecraft was flown back to Earth where the three astronauts splashed down safely in the Pacific Ocean on February 9.
Astronauts and key Mission Control personnel.
The mission commander of Apollo 14, Alan Shepard, one of the original Mercury Seven astronauts, became the first American to enter space with a suborbital flight on May 5, 1961. Thereafter, he was grounded by Ménière's disease, a disorder of the ear, and served as Chief Astronaut, the administrative head of the Astronaut Office. He had experimental surgery in 1968 which was successful and allowed his return to flight status. Shepard, at age 47, was the oldest U.S. astronaut to fly when he made his trip aboard Apollo 14, and he is the oldest person to walk on the Moon.
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Apollo 14's Command Module Pilot (CMP), Stuart Roosa, aged 37 when the mission flew, had been a smoke jumper before joining the Air Force in 1953. He became a fighter pilot and then in 1965 successfully completed Aerospace Research Pilot School (ARPS) at Edwards Air Force Base in California prior to his selection as a Group 5 astronaut the following year. He served as a capsule communicator (CAPCOM) for Apollo 9. The Lunar Module Pilot (LMP), Edgar Mitchell, aged 40 at the time of Apollo 14, joined the Navy in 1952 and served as a fighter pilot, beginning in 1954. He was assigned to squadrons aboard aircraft carriers before returning to the United States to further his education while in the Navy, also completing the ARPS prior to his selection as a Group 5 astronaut. He served on the support crew for Apollo 9 and was the LMP of the backup crew for Apollo 10.
Shepard and his crew had originally been designated by Deke Slayton, Director of Flight Crew Operations and one of the Mercury Seven, as the crew for Apollo 13. NASA's management felt that Shepard needed more time for training given he had not flown in space since 1961, and chose him and his crew for Apollo 14 instead. The crew originally designated for Apollo 14, Jim Lovell as the commander, Ken Mattingly as CMP and Fred Haise as LMP, all of whom had backed up Apollo 11, was made the prime crew for Apollo 13 instead.
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Mitchell's commander on the Apollo 10 backup crew had been another of the original seven, Gordon Cooper, who had tentatively been scheduled to command Apollo 13, but according to author Andrew Chaikin, his casual attitude toward training resulted in him being not selected. Also on that crew, but excluded from further flights, was Donn Eisele, likely because of problems aboard Apollo 7, which he had flown, and because he had been involved in a messy divorce.
Apollo 14's backup crew was Eugene A. Cernan as commander, Ronald E. Evans Jr. as CMP and Joe H. Engle as LMP. The backup crew, with Harrison Schmitt replacing Engle, would become the prime crew of Apollo 17. Schmitt flew instead of Engle because there was intense pressure on NASA to fly a scientist to the Moon (Schmitt was a geologist) and Apollo 17 was the last lunar flight. Engle, who had flown the X-15 to the edge of outer space, flew into space for NASA in 1981 on STS-2, the second Space Shuttle flight.
During projects Mercury and Gemini, each mission had a prime and a backup crew. Apollo 9 commander James McDivitt believed meetings that required a member of the flight crew were being missed, so for Apollo a third crew of astronauts was added, known as the support crew. Usually low in seniority, support crew members assembled the mission's rules, flight plan, and checklists, and kept them updated; for Apollo 14, they were Philip K. Chapman, Bruce McCandless II, William R. Pogue and C. Gordon Fullerton. CAPCOMs, the individuals in Mission Control responsible for communications with the astronauts were Evans, McCandless, Fullerton and Haise. A veteran of Apollo 13, which had aborted before reaching the Moon, Haise put his training for that mission to use, especially during the EVAs, since both missions were targeted at the same place on the Moon. Had Haise walked on the Moon, he would have been the first Group 5 astronaut to do so, an honor that went to Mitchell.
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The flight directors during Apollo had a one-sentence job description, "The flight director may take any actions necessary for crew safety and mission success." For Apollo 14, they were: Pete Frank, Orange team; Glynn Lunney, Black team; Milt Windler, Maroon team and Gerry Griffin, Gold team.
Preparation and training.
Prime and backup crews for both Apollo 13 and 14 were announced on August 6, 1969. Apollo 14 was scheduled for July 1970, but in January of that year, due to budget cuts that saw the cancellation of Apollo 20, NASA decided there would be two Apollo missions per year with 1970 to see Apollo 13 in April and Apollo 14 likely in October or November.
The investigation into the accident which caused an abort of Apollo 13 delayed Apollo 14. On May 7, 1970, NASA Administrator Thomas O. Paine announced that Apollo 14 would launch no earlier than December 3, and the landing would be close to the site targeted by Apollo 13. The Apollo 14 astronauts continued their training. On June 30, 1970, following the release of the accident report and a NASA review of what changes to the spacecraft would be necessary, NASA announced that the launch would slip to no earlier than January 31, 1971.
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The crew of Apollo 14 trained together for 19 months after assignment to the mission, longer than any other Apollo crew to that point. In addition to the normal training workload, they had to supervise the changes to the command and service module (CSM) made as a result of the Apollo 13 investigation, much of which was delegated by Shepard to Roosa. Mitchell later stated, "We realized that if our mission failed—if we had to turn back—that was probably the end of the Apollo program. There was no way NASA could stand two failures in a row. We figured there was a heavy mantle on our shoulders to make sure we got it right."
Before the abort of the Apollo 13 mission, the plan was to have Apollo 14 land near Littrow crater, in Mare Serenitatis, where there are features that were thought to be volcanic. After Apollo 13 returned, it was decided that its landing site, near Cone crater in the Fra Mauro formation, was scientifically more important than Littrow. The Fra Mauro formation is composed of ejecta from the impact event that formed Mare Imbrium, and scientists hoped for samples that originated deep under the Moon's surface. Cone crater was the result of a young, deep impact, and large enough to have torn through whatever debris was deposited since the Imbrium Event, which geologists hoped to be able to date. Landing at Fra Mauro would also allow orbital photography of another candidate landing site, the Descartes Highlands, which became the landing site for Apollo 16. Although Littrow went unvisited, a nearby area, Taurus-Littrow, was the landing site for Apollo 17. Apollo 14's landing site was located slightly closer to Cone crater than the point designated for Apollo 13.
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The change in landing site from Littrow to Fra Mauro affected the geological training for Apollo 14. Before the switch, the astronauts had been taken to volcanic sites on Earth; afterwards, they visited crater sites, such as the Ries Crater in West Germany and an artificial crater field created for astronaut training in Arizona's Verde Valley. The effectiveness of the training was limited by a lack of enthusiasm shown by Shepard, which set the tone for Mitchell. Harrison Schmitt suggested that the commander had other things on his mind, such as overcoming a ten-year absence from spaceflight and ensuring a successful mission after the near-disaster of Apollo 13.
Roosa undertook training for his period alone in lunar orbit, when he would make observations of the Moon and take photographs. He had been impressed by the training given to Apollo 13 prime crew CMP Mattingly by geologist Farouk El-Baz and got El-Baz to agree to undertake his training. The two men pored over lunar maps depicting the areas the CSM would pass over. When Shepard and Mitchell were on their geology field trips, Roosa would be overhead in an airplane taking photographs of the site and making observations. El-Baz had Roosa make observations while flying his T-38 jet at a speed and altitude simulating the speed at which the lunar surface would pass below the CSM.
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Another issue that had marked Apollo 13 was the last-minute change of crew due to exposure to communicable disease. To prevent another such occurrence, for Apollo 14 NASA instituted what was called the Flight Crew Health Stabilization Program. Beginning 21 days before launch, the crew lived in quarters at the launch site, Florida's Kennedy Space Center (KSC), with their contacts limited to their spouses, the backup crew, mission technicians, and others directly involved in training. Those individuals were given physical examinations and immunizations, and crew movements were limited as much as possible at KSC and nearby areas.
The Command and Service Modules were delivered to KSC on November 19, 1969; the ascent stage of the LM arrived on November 21 with the descent stage three days later. Thereafter, checkout, testing and equipment installation proceeded. The launch vehicle stack, with the spacecraft on top, was rolled out from the Vehicle Assembly Building to Pad 39A on November 9, 1970.
Hardware.
Spacecraft.
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The Apollo 14 spacecraft consisted of Command Module (CM) 110 and Service Module (SM) 110 (together CSM-110), called "Kitty Hawk", and Lunar Module 8 (LM-8), called "Antares". Roosa had chosen the CSM's call sign after the town in North Carolina where, in 1903, the Wright Brothers first flew their "Wright Flyer" airplane (also known as "Kitty Hawk"). Antares was named by Mitchell after the star in the constellation Scorpius that the astronauts in the LM would use to orient the craft for its lunar landing. Also considered part of the spacecraft were a Launch Escape System and a Spacecraft/Launch Vehicle Adapter, numbered SLA-17.
The changes to the Apollo spacecraft between Apollo 13 and 14 were more numerous than with earlier missions, not only because of the problems with Apollo 13, but because of the more extensive lunar activities planned for Apollo 14. The Apollo 13 accident had been caused by the explosive failure of an oxygen tank, after the insulation of the internal wiring had been damaged by heating of the tank contents pre-launch—that the oxygen had gotten hot enough to damage the insulation had not been realized, since the protective thermostatic switches had failed because they were, through an error, not designed to handle the voltage applied during ground testing. The explosion damaged the other tank or its tubing, causing its contents to leak away.
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The changes in response included a redesign of the oxygen tanks, with the thermostats being upgraded to handle the proper voltage. A third tank was also added, placed in Bay1 of the SM, on the side opposite the other two, and was given a valve that could isolate it in an emergency, and allow it to feed the CM's environmental system only. The quantity probe in each tank was upgraded from aluminum to stainless steel.
Also in response to the Apollo 13 accident, the electrical wiring in Bay4 (where the explosion had happened) was sheathed in stainless steel. The fuel cell oxygen supply valves were redesigned to isolate the Teflon-coated wiring from the oxygen. The spacecraft and Mission Control monitoring systems were modified to give more immediate and visible warnings of anomalies. The Apollo 13 astronauts had suffered shortages of water and of power after the accident. Accordingly, an emergency supply of of water was stored in Apollo 14's CM, and an emergency battery, identical to those that powered the LM's descent stage, was placed in the SM. The LM was modified to make the transfer of power from LM to CM easier.
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Other changes included the installation of anti-slosh baffles in the LM descent stage's propellant tanks. This would prevent the low fuel light from coming on prematurely, as had happened on Apollo 11 and 12. Structural changes were made to accommodate the equipment to be used on the lunar surface, including the Modular Equipment Transporter.
Launch vehicle.
The Saturn V used for Apollo 14 was designated SA-509, and was similar to those used on Apollo 8 through 13. At , it was the heaviest vehicle yet flown by NASA, heavier than the launch vehicle for Apollo 13.
A number of changes were made to avoid pogo oscillations, that had caused an early shutdown of the center J-2 engine on Apollo 13's S-II second stage. These included a helium gas accumulator installed in the liquid oxygen (LOX) line of the center engine, a backup cutoff device for that engine, and a simplified 2-position propellant utilization valve on each of the five J-2 engines.
ALSEP and other lunar surface equipment.
The Apollo Lunar Surface Experiments Package (ALSEP) array of scientific instruments carried by Apollo 14 consisted of the Passive Seismic Experiment (PSE), Active Seismic Experiment (ASE), Suprathermal Ion Detector Experiment (SIDE), Cold Cathode Ion Gauge Experiment (CCIG), and Charged Particle Lunar Environment Experiment (CPLEE). Two additional lunar surface experiments not part of the ALSEP were also flown, the Laser Ranging Retroreflector (LRRR or LR3), to be deployed in the ALSEP's vicinity, and the Lunar Portable Magnetometer (LPM), to be used by the astronauts during their second EVA. The PSE had been flown on Apollo 12 and 13, the ASE on Apollo 13, the SIDE on Apollo 12, the CCIG on Apollo 12 and 13, and the LRRR on Apollo 11. The LPM was new, but resembled equipment flown on Apollo 12. The ALSEP components flown on Apollo 13 were destroyed when its LM burned up in Earth's atmosphere.
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Deployment of the ALSEP, and of the other instruments, each formed one of Apollo 14's mission objectives.
The PSE was a seismometer, similar to one left on the Moon by Apollo 12, and was to measure seismic activity in the Moon. The Apollo 14 instrument would be calibrated by the impact, after being jettisoned, of the LM's ascent stage, since an object of known mass and velocity would be impacting at a known location on the Moon. The Apollo 12 instrument would also be activated by the spent Apollo 14 S-IVB booster, which would impact the Moon after the mission entered lunar orbit. The two seismometers would, in combination with those left by later Apollo missions, constitute a network of such instruments at different locations on the Moon.
The ASE would also measure seismic waves. It consisted of two parts. In the first, one of the crew members would deploy three geophones at distances up to from the ALSEP's Central Station, and on his way back from the furthest, fire thumpers every . The second consisted of four mortars (with their launch tubes), of different properties and set to impact at different distances from the experiment. It was hoped that the waves generated from the impacts would provide data about seismic wave transmission in the Moon's regolith. The mortar shells were not to be fired until the astronauts had returned to Earth, and in the event were never fired for fear they would damage other experiments. A similar experiment was successfully deployed, and the mortars launched, on Apollo 16.
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The LPM was to be carried during the second EVA and used to measure the Moon's magnetic field at various points.
The SIDE measured ions on the lunar surface, including from the solar wind. It was combined with the CCIG, which was to measure the lunar atmosphere and detect if it varied over time. The CPLEE measured the particle energies of protons and electrons generated by the Sun that reached the lunar surface. The LRRR acts as a passive target for laser beams, allowing the measurement of the Earth/Moon distance and how it changes over time. The LRRRs from Apollo 11, 14 and 15 are the only experiments left on the Moon by the Apollo astronauts that are still returning data.
Flown for the first time on Apollo 14 was the Buddy Secondary Life Support System (BSLSS), a set of flexible hoses that would enable Shepard and Mitchell to share cooling water should one of their Primary Life Support System (PLSS) backpacks fail. In such an emergency, the astronaut with the failed equipment would get oxygen from his Oxygen Purge System (OPS) backup cylinder, but the BSLSS would ensure he did not have to use oxygen for cooling, extending the life of the OPS. The OPSs used on Apollo 14 were modified from those used on previous missions in that the internal heaters were removed as unnecessary.
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Water bags were also taken to the lunar surface, dubbed "Gunga Dins", for insertion in the astronauts' helmets, allowing them sips of water during the EVAs. These had been flown on Apollo 13, but Shepard and Mitchell were the first to use them on the Moon. Similarly, Shepard was the first on the lunar surface to wear a spacesuit with commander's stripes: red stripes on arms, legs, and on the helmet, though one had been worn by Lovell on Apollo 13. These were instituted because of the difficulty in telling one spacesuited astronaut from the other in photographs.
Modular Equipment Transporter.
The Modular Equipment Transporter (MET) was a two-wheeled handcart, used only on Apollo 14, intended to allow the astronauts to take tools and equipment with them, and store lunar samples, without needing to carry them. On later Apollo program missions, the self-propelled Lunar Roving Vehicle (LRV) was flown instead.
The MET, when deployed for use on the lunar surface, was about long, wide and high. It had pressurized rubber tires wide and in diameter, containing nitrogen and inflated to about . The first use of tires on the Moon, these were developed by Goodyear and were dubbed their XLT (Experimental Lunar Tire) model. Fully loaded, the MET weighed about . Two legs combined with the wheels to provide four-point stability when at rest.
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Mission highlights.
Launch and flight to lunar orbit.
Apollo 14 launched from Launch Complex 39-A at KSC at 4:03:02 pm (21:03:02 UTC), January 31, 1971. This followed a launch delay due to weather of 40 minutes and 2 seconds; the first such delay in the Apollo program. The original planned time, 3:23 pm, was at the very start of the launch window of just under four hours; had Apollo 14 not launched during it, it could not have departed until March. Apollo 12 had launched during poor weather and twice been struck by lightning, as a result of which the rules had been tightened. Among those present to watch the launch were U.S. Vice President Spiro T. Agnew and the Prince of Spain, the future King Juan Carlos I. The mission would take a faster trajectory to the Moon than planned, and thus make up the time in flight. Because it had, just over two days after launch, the mission timers would be put ahead by 40 minutes and 3 seconds so that later events would take place at the times scheduled in the flight plan.
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The crew settled in for its voyage to Fra Mauro. At 60:30 Ground Elapsed Time, Shepard and Mitchell entered the LM to check its systems; while there they photographed a wastewater dump from the CSM, part of a particle contamination study in preparation for Skylab. Two midcourse corrections were performed on the translunar coast, with one burn lasting 10.19 seconds and one lasting 0.65 seconds.
Lunar orbit and descent.
At 81:56:40.70 into the mission (February 4 at 1:59:43 am EST; 06:59:43 UTC), the Service Propulsion System engine in the SM was fired for 370.84 seconds to send the craft into a lunar orbit with apocynthion of and pericynthion of . A second burn, at 86:10:52 mission time, sent the spacecraft into an orbit of by . This was done in preparation for the release of the LM "Antares". Apollo 14 was the first mission on which the CSM propelled the LM to the lower orbit—though Apollo 13 would have done so had the abort not already occurred. This was done to increase the amount of hover time available to the astronauts, a safety factor since Apollo 14 was to land in rough terrain.
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After separating from the command module in lunar orbit, the LM "Antares" had two serious problems. First, the LM computer began getting an ABORT signal from a faulty switch. NASA believed the computer might be getting erroneous readings like this if a tiny ball of solder had shaken loose and was floating between the switch and the contact, closing the circuit. The immediate solution – tapping on the panel next to the switch – did work briefly, but the circuit soon closed again. If the problem recurred after the descent engine fired, the computer would think the signal was real and would initiate an auto-abort, causing the ascent stage to separate from the descent stage and climb back into orbit. NASA and the software teams at the Massachusetts Institute of Technology scrambled to find a solution. The software was hard-wired, preventing it from being updated from the ground. The fix made it appear to the system that an abort had already happened, and it would ignore incoming automated signals to abort. This would not prevent the astronauts from piloting the ship, though if an abort became necessary, they might have to initiate it manually. Mitchell entered the changes with minutes to go until planned ignition.
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A second problem occurred during the powered descent, when the LM landing radar failed to lock automatically onto the Moon's surface, depriving the navigation computer of vital information on the vehicle's altitude and vertical descent speed. After the astronauts cycled the landing radar breaker, the unit successfully acquired a signal near . Mission rules required an abort if the landing radar was out at , though Shepard might have tried to land without it. With the landing radar, Shepard steered the LM to a landing which was the closest to the intended target of the six missions that landed on the Moon.
Lunar surface operations.
Shepard stated, after stepping onto the lunar surface, "And it's been a long way, but we're here." The first EVA began at 9:42 am EST (14:42 UTC) on February 5, 1971, having been delayed by a problem with the communications system which set back the start of the first EVA to five hours after landing. The astronauts devoted much of the first EVA to equipment offloading, deployment of the ALSEP and the US flag, as well as setting up and loading the MET. These activities were televised back to Earth, though the picture tended to degenerate during the latter portion of the EVA. Mitchell deployed the ASE's geophone lines, unreeling and emplacing the two lines leading out from the ALSEP's Central Station. He then fired the thumper explosives, vibrations from which would give scientists back on Earth information about the depth and composition of the lunar regolith. Of the 21 thumpers, five failed to fire. On the way back to the LM, the astronauts collected and documented lunar samples, and took photographs of the area. The first EVA lasted 4 hours, 47 minutes, 50 seconds.
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The astronauts had been surprised by the undulating ground, expecting flatter terrain in the area of the landing, and this became an issue on the second EVA, as they set out, MET in tow, for the rim of Cone crater. The craters that Shepard and Mitchell planned to use for navigational landmarks looked very different on the ground than on the maps they had, based on overhead shots taken from lunar orbit. Additionally, they consistently overestimated the distance they travelled. Mission Control and the CAPCOM, Fred Haise, could see nothing of this, as the television camera remained near the LM, but they worried as the clock ticked on the EVA, and monitored the heavy breathing and rapid heartbeats of the astronauts. They topped one ridge that they expected was the crater rim, only to view more such terrain beyond. Although Mitchell strongly suspected the rim was nearby, they had become physically exhausted from the effort. They were then instructed by Haise to sample where they were and then start moving back towards the LM. Later analysis using the pictures they took determined that they had come within about of the crater's rim. Images from the Lunar Reconnaissance Orbiter (LRO) show the tracks of the astronauts and the MET come to within 30 m of the rim. The difficulties faced by Shepard and Mitchell would emphasize the need for a means of transportation on the lunar surface with a navigation system, which was met by the Lunar Roving Vehicle, already planned to fly on Apollo 15.
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Once the astronauts returned to the vicinity of the LM and were again within view of the television camera, Shepard performed a stunt he had been planning for years in the event he reached the Moon, and which is probably what Apollo 14 is best remembered for. Shepard brought along a Wilson six iron golf club head, which he had modified to attach to the handle of the contingency sample tool, and two golf balls. Shepard took several one-handed swings (due to the limited flexibility of the EVA suit) and exuberantly exclaimed that the second ball went "miles and miles and miles" in the low lunar gravity. Mitchell then threw a lunar scoop handle as if it were a javelin. The "javelin" and one of the golf balls wound up in a crater together, with Mitchell's projectile a bit further. In an interview with Ottawa Golf, Shepard stated the other landed near the ALSEP. The second EVA lasted 4 hours, 34 minutes, 41 seconds. Shepard brought back the club, gave it to the USGA Museum in New Jersey, and had a replica made which he gave to the National Air and Space Museum. In February 2021, to commemorate Apollo 14's 50th anniversary, imaging specialist Andy Saunders, who had previously worked to produce the clearest image of Neil Armstrong on the Moon, produced new, digitally enhanced images that were used to estimate the final resting places of the two balls that Shepard hit - the first landed approximately 24 yards from the "tee", while the second managed 40 yards.
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Lunar samples.
A total of of Moon rocks, or lunar samples, were brought back from Apollo 14. Most are breccias, which are rocks composed of fragments of other, older rocks. Breccias form when the heat and pressure of meteorite impacts fuse small rock fragments together. There were a few basalts that were collected in this mission in the form of clasts (fragments) in breccia. The Apollo 14 basalts are generally richer in aluminum and sometimes richer in potassium than other lunar basalts. Most lunar mare basalts collected during the Apollo program were formed from 3.0 to 3.8 billion years ago. The Apollo 14 basalts were formed 4.0 to 4.3 billion years ago, older than the volcanism known to have occurred at any of the mare locations reached during the Apollo program.
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In January 2019 research showed that Big Bertha, which weighs , has characteristics that make it likely to be a terrestrial (Earth) meteorite. Granite and quartz, which are commonly found on Earth but very rarely found on the Moon, were confirmed to exist on Big Bertha. To find the sample's age, the research team from Curtin University looked at bits of the mineral zircon embedded in its structure. "By determining the age of zircon found in the sample, we were able to pinpoint the age of the host rock at about four billion years old, making it similar to the oldest rocks on Earth," researcher Alexander Nemchin said, adding that "the chemistry of the zircon in this sample is very different from that of every other zircon grain ever analyzed in lunar samples, and remarkably similar to that of zircons found on Earth." This would mean Big Bertha is both the first discovered terrestrial meteorite and the oldest known Earth rock.
Lunar orbit operations.
Roosa spent almost two days alone aboard "Kitty Hawk", performing the first intensive program of scientific observation from lunar orbit, much of which was intended to have been done by Apollo 13. After "Antares" separated and its crew began preparations to land, Roosa in "Kitty Hawk" performed an SPS burn to send the CSM to an orbit of approximately , and later a plane change maneuver to compensate for the rotation of the Moon.
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Roosa took pictures from lunar orbit. The Lunar Topographic Camera, also known as the Hycon camera, was supposed to be used to image the surface, including the Descartes Highlands site being considered for Apollo 16, but it quickly developed a fault with the shutter that Roosa could not fix despite considerable help from Houston. Although about half of the photographic targets had to be scrubbed, Roosa was able to obtain photographs of Descartes with a Hasselblad camera and confirm that it was a suitable landing point. Roosa also used the Hasselblad to take photographs of the impact point of Apollo 13's S-IVB near Lansburg B crater. After the mission, troubleshooting found a tiny piece of aluminum contaminating the shutter control circuit, which caused the shutter to operate continuously.
Roosa was able to see sunlight glinting off "Antares" and view its lengthy shadow on the lunar surface on Orbit 17; on Orbit 29 he could see the sun reflecting off the ALSEP. He also took astronomical photographs, of the Gegenschein, and of the Lagrangian point of the Sun-Earth system that lies beyond the Earth (L), testing the theory that the Gegenschein is generated by reflections off particles at L. Performing the bistatic radar experiment, he also focused "Kitty Hawk" VHF and S-band transmitters at the Moon so that they would bounce off and be detected on Earth in an effort to learn more about the depth of the lunar regolith.
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Return, splashdown and quarantine.
"Antares" lifted off from the Moon at 1:48:42 pm EST (18:48:42 UTC) on February 6, 1971. Following the first direct (first orbit) rendezvous on a lunar landing mission, docking took place an hour and 47 minutes later. Despite concerns based on the docking problems early in the mission, the docking was successful on the first attempt, though the LM's Abort Guidance System, used for navigation, failed just before the two craft docked. After crew, equipment, and lunar samples were transferred to "Kitty Hawk", the ascent stage was jettisoned, and impacted the Moon, setting off waves registered by the seismometers from Apollo 12 and 14.
A trans-earth injection burn took place on February 6 at 8:39:04 pm (February 7 at 01:39:04 UTC) taking 350.8 seconds, during "Kitty Hawk" 34th lunar revolution. During the trans-earth coast, two tests of the oxygen system were performed, one to ensure the system would operate properly with low densities of oxygen in the tanks, the second to operate the system at a high flow rate, as would be necessary for the in-flight EVAs scheduled for Apollo 15 and later. Additionally, a navigation exercise was done to simulate a return to Earth following a loss of communications. All were successful. During his rest periods on the voyage, Mitchell conducted ESP experiments without NASA's knowledge or sanction, attempting by prearrangement to send images of cards he had brought with him to four people on Earth. He stated after the mission that two of the four had gotten 51 out of 200 correct (the others were less successful), whereas random chance would have dictated 40.
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On the final evening in space, the crew conducted a press conference, with the questions submitted to NASA in advance and read to the astronauts by the CAPCOM.
The command module "Kitty Hawk" splashed down in the South Pacific Ocean on February 9, 1971, at 21:05 [UTC], approximately south of American Samoa. After recovery by the ship USS "New Orleans", the crew was flown to Pago Pago International Airport in Tafuna, then to Honolulu, then to Ellington Air Force Base near Houston in a plane containing a Mobile Quarantine Facility trailer before they continued their quarantine in the Lunar Receiving Laboratory. They remained there until their release from quarantine on February 27, 1971. The Apollo 14 astronauts were the last lunar explorers to be quarantined on their return from the Moon. They were the only Apollo crew to be quarantined both before and after the flight.
Roosa, who worked in forestry in his youth, took several hundred tree seeds on the flight. These were germinated after the return to Earth, and were widely distributed around the world as commemorative Moon trees. Some seedlings were given to state forestry associations in 1975 and 1976 to mark the United States Bicentennial.
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Mission insignia.
The mission insignia is an oval depicting the Earth and the Moon, and an astronaut pin drawn with a comet trail. The pin is leaving Earth and is approaching the Moon. A gold band around the edge includes the mission and astronaut names. The designer was Jean Beaulieu, who based it on a sketch by Shepard, who had been head of the Astronaut Office and meant the pin to symbolize that through him, the entire corps was in spirit flying to the Moon.
The backup crew spoofed the patch with its own version, with revised artwork showing a Wile E. Coyote cartoon character depicted as gray-bearded (for Shepard, who was 47 at the time of the mission and the oldest man on the Moon), pot-bellied (for Mitchell, who had a pudgy appearance) and red-furred (for Roosa's red hair), still on the way to the Moon, while Road Runner (for the backup crew) is already on the Moon, holding a U.S. flag and a flag labelled "1st Team". The flight name is replaced by "BEEP BEEP" and the backup crew's names are given. Several of these patches were hidden by the backup crew and found during the flight by the crew in notebooks and storage lockers in both the CSM "Kitty Hawk" and the LM "Antares", and one patch was stored in the MET lunar handcart. One patch, attached to Shepard's PLSS, was worn on the lunar surface, and, mounted on a plaque, was presented by him to Cernan after the mission.
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Spacecraft locations.
The Apollo 14 command module "Kitty Hawk" is on display at the Apollo/Saturn V Center at the Kennedy Space Center Visitor Complex after being on display at the United States Astronaut Hall of Fame near Titusville, Florida, for several years. At the time of its transfer of ownership from NASA to the Smithsonian in July 1977, it was on display at the facilities of North American Rockwell (the company that had constructed it) in Downey, California. The SM reentered Earth's atmosphere and was destroyed, though there was no tracking or sightings of it.
The S-IVB booster impacted the Moon on February4 at . The ascent stage of lunar module "Antares" impacted the Moon on February7, 1971, at 00:45:25.7 UT (February 6, 7:45 pm EST), at . "Antares"' descent stage and the mission's other equipment remain at Fra Mauro at .
Photographs taken in 2009 by the Lunar Reconnaissance Orbiter were released on July 17, and the Fra Mauro equipment was the most visible Apollo hardware at that time, owing to particularly good lighting conditions. In 2011, the LRO returned to the landing site at a lower altitude to take higher resolution photographs.
External links.
NASA reports
Multimedia
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Apollo 15
Apollo 15 (July 26August 7, 1971) was the ninth crewed mission in the Apollo program and the fourth Moon landing. It was the first J mission, with a longer stay on the Moon and a greater focus on science than earlier landings. Apollo 15 saw the first use of the Lunar Roving Vehicle.
The mission began on July 26 and ended on August 7, with the lunar surface exploration taking place between July 30 and August 2. Commander David Scott and Lunar Module Pilot James Irwin landed near Hadley Rille and explored the local area using the rover, allowing them to travel further from the Lunar Module than had been possible on previous missions. They spent 18 hours on the Moon's surface on four extravehicular activities (EVA), and collected of surface material.
At the same time, Command Module Pilot Alfred Worden orbited the Moon, operating the sensors in the scientific instrument module (SIM) bay of the service module. This suite of instruments collected data on the Moon and its environment using a panoramic camera, a gamma-ray spectrometer, a mapping camera, a laser altimeter, a mass spectrometer, and a lunar subsatellite deployed at the end of the moonwalks. The Lunar Module returned safely to the command module and, at the end of Apollo 15's 74th lunar orbit, the engine was fired for the journey home. During the return trip, Worden performed the first spacewalk in deep space. The Apollo 15 mission splashed down safely on August7 despite the partial opening of one of its three parachutes.
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The mission accomplished its goals and also saw the collection of the Genesis Rock, thought to be part of the Moon's early crust, and Scott's use of a hammer and a feather to validate Galileo's theory that when there is no air resistance, objects fall at the same rate due to gravity regardless of their mass. The mission received negative publicity the following year when it emerged that the crew had carried unauthorized postal covers to the lunar surface, some of which were sold by a West German stamp dealer. The members of the crew were reprimanded for poor judgment, and did not fly in space again.
Background.
In 1962, NASA contracted for the construction of fifteen Saturn V rockets to achieve the Apollo program's goal of a crewed landing on the Moon by 1970; at the time no one knew how many missions this would require. In 1969 Apollo 11 succeeded in landing on the Moon with the sixth SaturnV, so nine rockets remained available for a hoped-for total of ten landings. These plans included a heavier, extended version of the Apollo spacecraft to be used in the last five missions (Apollo 16 through 20). The revamped Lunar Module would be capable of up to a 75-hour stay, and would carry a Lunar Roving Vehicle to the Moon's surface. The service module would house a package of orbital experiments to gather data on the Moon. In the original plan Apollo 15 was to be the last of the non-extended missions to land in Censorinus crater. But in anticipation of budget cuts, NASA cancelled three landing missions by September 1970. Apollo 15 became the first of three extended missions, known as J missions, and the landing site was moved to Hadley Rille, originally planned for Apollo 19.
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Crew and key Mission Control personnel.
Crew.
Scott was born in 1932 in San Antonio, Texas, and, after spending his freshman year at the University of Michigan on a swimming scholarship, transferred to the United States Military Academy, from which he graduated in 1954. Serving in the Air Force, Scott had received two advanced degrees from MIT in 1962 before being selected as one of the third group of astronauts the following year. He flew in Gemini 8 in 1966 alongside Neil Armstrong and as command module pilot of Apollo 9 in 1969. Worden was born in 1932 in Jackson, Michigan, and like his commander, had attended West Point (class of 1955) and served in the Air Force. Worden earned two master's degrees in engineering from Michigan in 1963. Irwin had been born in 1930 in Pittsburgh, and had attended the United States Naval Academy, graduating in 1951 and serving in the Air Force, receiving a master's degree from Michigan in 1957. Both Worden and Irwin were selected in the fifth group of astronauts (1966), and Apollo 15 would be their only spaceflight. All three future astronauts had attended Michigan, and two had taken degrees from there; it had been the first university to offer an aeronautical engineering program.
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The backup crew was Richard F. Gordon Jr. as commander, Vance D. Brand as command module pilot and Harrison H. Schmitt as Lunar Module pilot. By the usual rotation of crews, the three would most likely have flown Apollo 18, which was canceled. Brand flew later on the Apollo–Soyuz Test Project and on STS-5, the first operational Space Shuttle mission. With NASA under intense pressure to send a professional scientist to the Moon, Schmitt, a geologist, was selected as LMP of Apollo 17 instead of Joe Engle.
Apollo 15's support crew consisted of astronauts Joseph P. Allen, Robert A. Parker and Karl G. Henize. All three were scientist-astronauts, selected in 1967, as the prime crew felt they needed more assistance with the science than with the piloting. None of the support crew would fly during the Apollo program, waiting until the Space Shuttle program to go into space.
Mission Control.
The flight directors for Apollo 15 were as follows:
During a mission the capsule communicators (CAPCOMs), always fellow astronauts, were the only people who normally would speak to the crew. For Apollo 15, the CAPCOMs were Allen, Brand, C. Gordon Fullerton, Gordon, Henize, Edgar D. Mitchell, Parker, Schmitt and Alan B. Shepard.
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Planning and training.
Schmitt and other scientist-astronauts advocated for a greater place for science on the early Apollo missions. They were often met with disinterest from other astronauts, or found science displaced by higher priorities. Schmitt realized that what was needed was an expert teacher who could fire the astronauts' enthusiasm, and contacted Caltech geologist Lee Silver, whom Schmitt introduced to Apollo 13's commander, Jim Lovell, and to its Lunar Module pilot, Fred Haise, then in training for their mission. Lovell and Haise were willing to go on a field expedition with Silver, and geology became a significant part of their training. Geologist Farouk El-Baz trained the prime crew's command module pilot, Ken Mattingly to inform his planned observations from lunar orbit. The crew's newly acquired skills mostly went unused, due to the explosion that damaged the Apollo 13 spacecraft, and caused an abort of the mission. Apollo 14's CMP, Stuart Roosa, was enthusiastic about geology, but the mission commander, Shepard, less so.
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Already familiar with the spacecraft as the backup crew for Apollo 12, Scott, Worden and Irwin could devote more of their training time as prime crew for Apollo 15 to geology and sampling techniques. Scott was determined that his crew bring back the maximum amount of scientific data possible, and met with Silver in April 1970 to begin planning the geological training. Schmitt's assignment as Apollo 15's backup LMP made him an insider, and allowed him to spark competition between the prime and backup crews. The cancellation of two Apollo missions in September 1970 transformed Apollo 15 into a J mission, with a longer stay on the lunar surface, and the first Lunar Roving Vehicle (LRV). This change was welcomed by Scott, who according to David West Reynolds in his account of the Apollo program, was "something more than a hotshot pilot. Scott had the spirit of a true explorer", one determined to get the most from the J mission. The additional need for communications, including from planned experiments and the rover, required the near-rebuilding of the Honeysuckle Creek Tracking Station in Australia.
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Geology field trips took place about once a month throughout the crew's 20 months of training. At first, Silver would take the commanders and LMPs from the prime and backup crews to geological sites in Arizona and New Mexico as if for a normal field geology lesson, but closer to launch, these trips became more realistic. Crews began to wear mock-ups of the backpacks they would carry while hiking near the Rio Grande Gorge, and communicate using walkie-talkies to a CAPCOM in a tent. The CAPCOM was accompanied by a geologist unfamiliar with the area who would rely on the astronauts' descriptions to interpret the findings, and familiarized the crew members with describing landscapes to people who could not see them. Considering himself a serious amateur, Scott came to enjoy field geology.
The decision to land at Hadley came in September 1970. The Site Selection Committee had narrowed the field down to two sites—Hadley Rille, a deep channel on the edge of Mare Imbrium close to the Apennine mountains or the crater Marius, near which were a group of low, possibly volcanic, domes. Although not ultimately his decision, the commander of a mission always held great sway. To David Scott the choice was clear, as Hadley "had more variety. There is a certain intangible quality which drives the spirit of exploration and I felt that Hadley had it. Besides it looked beautiful and usually when things look good they are good." The selection of Hadley was made although NASA lacked high resolution images of the landing site; none had been made as the site was considered too rough to risk one of the earlier Apollo missions. The proximity of the Apennine mountains to the Hadley site required a landing approach trajectory of 26 degrees, far steeper than the 15 degrees in earlier Apollo landings.
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The expanded mission meant that Worden spent much of his time at North American Rockwell's facilities at Downey, California, where the command and service module (CSM) was being built. He undertook a different kind of geology training. Working with El-Baz, he studied maps and photographs of the craters he would pass over while orbiting alone in the CSM. As El-Baz listened and gave feedback, Worden learned how to describe lunar features in a way that would be useful to the scientists who would listen to his transmissions back on Earth. Worden found El-Baz to be an enjoyable and inspiring teacher. Worden usually accompanied his crewmates on their geology field trips, though he was often in an airplane overhead, describing features of the landscape as the plane simulated the speed at which the lunar landscape would pass below the CSM.
The demands of the training strained both Worden's and Irwin's marriages; each sought Scott's advice, fearing a divorce might endanger their places on the mission as not projecting the image NASA wanted for the astronauts. Scott consulted Director of Flight Crew Operations Deke Slayton, their boss, who stated what was important was that the astronauts do their jobs. Although the Irwins overcame their marital difficulties, the Wordens divorced before the mission.
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Hardware.
Spacecraft.
Apollo 15 used command and service module CSM-112, which was given the call sign "Endeavour", named after HMS "Endeavour", and Lunar Module LM-10, call sign "Falcon", named after the United States Air Force Academy mascot. Scott explained the choice of the name "Endeavour" on the grounds that its captain, James Cook, had commanded the first purely scientific sea voyage, and Apollo 15 was the first lunar landing mission on which there was a heavy emphasis on science. Apollo 15 took with it a small piece of wood from Cook's ship, while "Falcon" carried two falcon feathers to the Moon in recognition of the crew's service in the Air Force. Also part of the spacecraft were a Launch Escape System and a Spacecraft-Lunar Module Adapter, numbered SLA-19.
Technicians at the Kennedy Space Center had some problems with the instruments in the service module's scientific instrument module (SIM) bay. Some instruments were late in arriving, and principal investigators or representatives of NASA contractors sought further testing or to make small changes. Mechanical problems came from the fact the instruments were designed to operate in space, but had to be tested on the surface of the Earth. As such, things like the 7.5 m (24 ft) booms for the mass and gamma ray spectrometers could be tested only using equipment that tried to mimic the space environment, and, in space, the mass spectrometer boom several times did not fully retract.
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On the Lunar Module, the fuel and oxidizer tanks were enlarged on both the descent and ascent stages, and the engine bell on the descent stage was extended. Batteries and solar cells were added for increased electrical power. In all this increased the weight of the Lunar Module to , heavier than previous models.
If Apollo 15 had flown as an H mission, it would have been with CSM-111 and LM-9. That CSM was used by the Apollo–Soyuz Test Project in 1975, but the lunar module went unused and is now at the Kennedy Space Center Visitor Complex. "Endeavour" is on display at the National Museum of the United States Air Force at Wright-Patterson Air Force Base in Dayton, Ohio, following its transfer of ownership from NASA to the Smithsonian in December 1974.
Launch vehicle.
The Saturn V that launched Apollo 15 was designated SA-510, the tenth flight-ready model of the rocket. As the payload of the rocket was greater, changes were made to the rocket and to its launch trajectory. It was launched in a more southerly direction (80–100 degrees azimuth) than previous missions, and the Earth parking orbit was lowered to . These two changes meant more could be launched. The propellant reserves were reduced and the number of retrorockets on the S-IC first stage (used to separate the spent first stage from the S-II second stage) reduced from eight to four. The four outboard engines of the S-IC would be burned longer and the center engine would also burn longer. Changes were also made to the S-II to dampen pogo oscillations.
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Once all major systems were installed in the SaturnV, it was moved from the Vehicle Assembly Building to the launch site, Launch Complex 39A. During late June and early July 1971, the rocket and Launch Umbilical Tower (LUT) were struck by lightning at least four times. There was no damage to the vehicle, and only minor damage to ground support equipment.
Space suits.
The Apollo 15 astronauts wore redesigned space suits. On all previous Apollo flights, including the non-lunar flights, the commander and lunar module pilot had worn suits with the life support, liquid cooling, and communications connections in two parallel rows of three. On Apollo 15, the new suits, dubbed the "A7LB", had the connectors situated in triangular pairs. This new arrangement, along with the relocation of the entry zipper (which went in an up-down motion on the old suits), to run diagonally from the right shoulder to the left hip, aided in suiting and unsuiting in the cramped confines of the spacecraft. It also allowed for a new waist joint, letting the astronauts bend completely over, and sit on the rover. Upgraded backpacks allowed for longer-duration moonwalks. As in all missions from and after Apollo 13, the commander's suit bore a red stripe on the helmet, arms and legs.
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Worden wore a suit similar to those worn by the Apollo 14 astronauts, but modified to interface with Apollo 15's equipment. Gear needed only for lunar surface EVAs, such as the liquid cooling garment, was not included with Worden's suit, as the only EVA he was expected to do was one to retrieve film cartridges from the SIM bay on the flight home.
Lunar Roving Vehicle.
A vehicle that could operate on the surface of the Moon had been considered by NASA since the early 1960s. An early version was called MOLAB, which had a closed cabin and would have massed about ; some scaled-down prototypes were tested in Arizona. As it became clear NASA would not soon establish a lunar base, such a large vehicle seemed unnecessary. Still, a rover would enhance the J missions, which were to concentrate on science, though its mass was limited to about and it was not then clear that so light a vehicle could be useful. NASA did not decide to proceed with a rover until May 1969, as Apollo 10, the dress rehearsal for the Moon landing, made its way home from lunar orbit. Boeing received the contract for three rovers on a cost-plus basis; overruns (especially in the navigation system) meant the three vehicles eventually cost a total of $40 million. These cost overruns gained considerable media attention at a time of greater public weariness with the space program, when NASA's budget was being cut.
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The Lunar Roving Vehicle could be folded into a space 5 ft by 20 in (1.5 m by 0.5 m). Unloaded, it weighed 460 lb (209 kg) and when carrying two astronauts and their equipment, 1500 lb (700 kg). Each wheel was independently driven by a horsepower (200 W) electric motor. Although it could be driven by either astronaut, the commander always drove. Travelling at speeds up to 6to 8mph (10to 12km/h), astronauts for the first time could travel far afield from their lander and still have enough time to do some scientific experiments. The Apollo 15 rover bore a plaque, reading: "Man's First Wheels on the Moon, Delivered by Falcon, July 30, 1971". During pre-launch testing, the LRV was given additional bracing, lest it collapse if someone sat on it under Earth conditions.
Particles and Fields Subsatellite.
The Apollo 15 Particles and Fields Subsatellite (PFS-1) was a small satellite released into lunar orbit from the SIM bay just before the mission left orbit to return to Earth. Its main objectives were to study the plasma, particle, and magnetic field environment of the Moon and map the lunar gravity field. Specifically, it measured plasma and energetic particle intensities and vector magnetic fields, and facilitated tracking of the satellite velocity to high precision. A basic requirement was that the satellite acquire fields and particle data everywhere on the orbit around the Moon. As well as measuring magnetic fields, the satellite contained sensors to study the Moon's mass concentrations, or mascons. The satellite orbited the Moon and returned data from August 4, 1971, until January 1973, when, following multiple failures of the subsatellite's electronics, ground support was terminated. It is believed to have crashed into the Moon sometime thereafter.
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Mission highlights.
Launch and outbound trip.
Apollo 15 was launched on July 26, 1971, at 9:34am EDT from the Kennedy Space Center at Merritt Island, Florida. The time of launch was at the very start of the two-hour, 37-minute launch window, which would allow Apollo 15 to arrive at the Moon with the proper lighting conditions at Hadley Rille; had the mission been postponed beyond another window on July 27, it could not have been rescheduled until late August. The astronauts had been awakened five and a quarter hours before launch by Slayton, and after breakfast and suiting up, had been taken to Pad 39A, launch site of all seven attempts at crewed lunar landing, and entered the spacecraft about three hours before launch. There were no unplanned delays in the countdown.
At 000:11:36 into the mission, the S-IVB engine shut down, leaving Apollo 15 in its planned parking orbit in low Earth orbit. The mission remained there for 2hours and 40 minutes, allowing the crew (and Houston, via telemetry) to check the spacecraft's systems. At 002:50.02.6 into the mission, the S-IVB was restarted for trans-lunar injection (TLI), placing the craft on a path to the Moon. Before TLI, the craft had completed 1.5 orbits around the Earth.
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The command and service module (CSM) and the Lunar Module remained attached to the nearly-exhausted S-IVB booster. Once trans-lunar injection had been achieved, placing the spacecraft on a trajectory towards the Moon, explosive cords separated the CSM from the booster as Worden operated the CSM's thrusters to push it away. Worden then maneuvered the CSM to dock with the LM (mounted on the end of the S-IVB), and the combined craft was then separated from the S-IVB by explosives. After Apollo 15 separated from the booster, the S-IVB maneuvered away, and, as planned, impacted the Moon about an hour after the crewed spacecraft entered lunar orbit, though due to an error the impact was away from the intended target. The booster's impact was detected by the seismometers left on the Moon by Apollo 12 and Apollo 14, providing useful scientific data.
There was a malfunctioning light on the craft's service propulsion system (SPS); after considerable troubleshooting, the astronauts did a test burn of the system that also served as a midcourse correction. This occurred about 028:40:00 into the mission. Fearing that the light meant the SPS might unexpectedly fire, the astronauts avoided using the control bank with the faulty light, bringing it online only for major burns, and controlling it manually. After the mission returned, the malfunction proved to be caused by a tiny bit of wire trapped within the switch.
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After purging and renewing the LM's atmosphere to eliminate any contamination, the astronauts entered the LM about 34 hours into the mission, needing to check the condition of its equipment and move in items that would be required on the Moon. Much of this work was televised back to Earth, the camera operated by Worden. The crew discovered a broken outer cover on the Range/Range Rate tapemeter. This was a concern not only because an important piece of equipment, providing information on distance and rate of approach, might not work properly, but because bits of the glass cover were floating around "Falcon" interior. The tapemeter was supposed to be in a helium atmosphere, but due to the breakage, it was in the LM's oxygen atmosphere. Testing on the ground verified the tapemeter would still work properly, and the crew removed most of the glass using a vacuum cleaner and adhesive tape.
As yet, there had been only minor problems, but at about 61:15:00 mission time (the evening of July 28 in Houston), Scott discovered a leak in the water system while preparing to chlorinate the water supply. The crew could not tell where it was coming from, and the issue had the potential to become serious. The experts in Houston found a solution, which was successfully implemented by the crew. The water was mopped up with towels, which were then put out to dry in the tunnel between the command module (CM) and Lunar Module—Scott stated it looked like someone's laundry.
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At 073:31:14 into the mission, a second midcourse correction, with less than a second of burn, was made. Although there were four opportunities to make midcourse corrections following TLI, only two were needed. Apollo 15 approached the Moon on July 29, and the lunar orbit insertion (LOI) burn had to be made using the SPS, on the far side of the Moon, out of radio contact with Earth. If no burn occurred, Apollo 15 would emerge from the lunar shadow and come back in radio contact faster than expected; the continued lack of communication allowed Mission Control to conclude that the burn had taken place. When contact resumed, Scott did not immediately give the particulars of the burn, but spoke admiringly of the beauty of the Moon, causing Alan Shepard, the Apollo 14 commander, who was awaiting a television interview, to grumble, "To hell with that shit, give us details of the burn." The 398.36-second burn took place at 078:31:46.7 into the mission at an altitude of above the Moon, and placed Apollo 15 in an elliptical lunar orbit of .
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Lunar orbit and landing.
On Apollo 11 and 12, the Lunar Module decoupled from the CSM and was piloted to a much lower orbit from which the lunar landing attempt commenced; to save fuel in an increasingly heavy lander, beginning with Apollo 14, the SPS in the service module made that burn, known as descent orbit insertion (DOI), with the lunar module still attached to the CSM. The initial orbit Apollo 15 was in had its apocynthion, or high point, over the landing site at Hadley; a burn at the opposite point in the orbit was performed, with the result that Hadley would now be under the craft's pericynthion, or low point. The DOI burn was performed at 082:39:49.09 and took 24.53 seconds; the result was an orbit with apocynthion of and pericynthion of . Overnight between July 29 and 30, as the crew rested, it became apparent to Mission Control that mass concentrations in the Moon were making Apollo 15's orbit increasingly elliptical—pericynthion was by the time the crew was awakened on July 30. This, and uncertainty as to the exact altitude of the landing site, made it desirable that the orbit be modified, or trimmed. Using the craft's RCS thrusters, this took place at 095:56:44.70, lasting 30.40 seconds, and raised the pericynthion to and the apocynthion to .
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As well as preparing the Lunar Module for its descent, the crew continued observations of the Moon (including of the landing site at Hadley) and provided television footage of the surface. Then, Scott and Irwin entered the Lunar Module in preparation for the landing attempt. Undocking was planned for 100:13:56, over the far side of the Moon, but nothing happened when separation was attempted. After analyzing the problem, the crew and Houston decided the probe instrumentation umbilical was likely loose or disconnected; Worden went into the tunnel connecting the command and lunar modules and determined this was so, seating it more firmly. With the problem resolved, "Falcon" separated from "Endeavour" at 100:39:16.2, about 25 minutes late, at an altitude of . Worden in "Endeavour" executed a SPS burn at 101:38:58.98 to send "Endeavour" to an orbit of by in preparation for his scientific work.
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Below about , Scott could see nothing of the surface because of the quantities of lunar dust being displaced by "Falcon" exhaust. "Falcon" had a larger engine bell than previous LMs, in part to accommodate a heavier load, and the importance of shutting down the engine at initial contact rather than risk "blowback", the exhaust reflecting off the lunar surface and going back into the engine (possibly causing an explosion) had been impressed on the astronauts by mission planners. Thus, when Irwin called "Contact", indicating that one of the probes on the landing leg extensions had touched the surface, Scott immediately shut off the engine, letting the lander fall the remaining distance to the surface. Already moving downward at about per second, "Falcon" dropped from a height of . Scott's speed resulted in what was likely the hardest lunar landing of any of the crewed missions, at about per second, causing a startled Irwin to yell "Bam!" Scott had landed "Falcon" on the rim of a small crater he could not see, and the lander settled back at an angle of 6.9 degrees and to the left of 8.6 degrees. Irwin described it in his autobiography as the hardest landing he had ever been in, and he feared that the craft would keep tipping over, forcing an immediate abort.
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"Falcon" landed at 104:42:29.3 (22:16:29 GMT on July 30), with approximately 103 seconds of fuel remaining, about from the planned landing site. After Irwin's exclamation, Scott reported, "Okay, Houston. The "Falcon" is on the Plain at Hadley." Once within the planned landing zone, the increased mobility provided by the Lunar Roving Vehicle made unnecessary any further maneuvering.
Lunar surface.
Stand-up EVA and first EVA.
With "Falcon" due to remain on the lunar surface for almost three days, Scott deemed it important to maintain the circadian rhythm they were used to, and as they had landed in the late afternoon, Houston time, the two astronauts were to sleep before going onto the surface. But the time schedule allowed Scott to open the lander's top hatch (usually used for docking) and spend a half hour looking at their surroundings, describing them, and taking photographs. Lee Silver had taught him the importance of going to a high place to survey a new field site, and the top hatch served that purpose. Deke Slayton and other managers were initially opposed due to the oxygen that would be lost, but Scott got his way. During the only stand-up extravehicular activity (EVA) ever performed through the LM's top hatch on the lunar surface, Scott was able to make plans for the following day's EVA. He offered Irwin a chance to look out as well, but this would have required rearranging the umbilicals connecting Irwin to "Falcon" life support system, and he declined. After repressurizing the spacecraft, Scott and Irwin removed their space suits for sleep, becoming the first astronauts to doff their suits while on the Moon.
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Throughout the sleep period Mission Control in Houston monitored a slow but steady oxygen loss. Scott and Irwin eventually were awakened an hour early, and the source of the problem was found to be an open valve on the urine transfer device. In post-mission debriefing, Scott recommended that future crews be woken at once under similar circumstances. After the problem was solved, the crew began preparation for the first Moon walk.
After donning their suits and depressurizing the cabin, Scott and Irwin began their first full EVA, becoming the seventh and eighth humans, respectively, to walk on the Moon. They began deploying the lunar rover, stored folded up in a compartment of "Falcon" descent stage, but this proved troublesome due to the slant of the lander. The experts in Houston suggested lifting the front end of the rover as the astronauts pulled it out, and this worked. Scott began a system checkout. One of the batteries gave a zero voltage reading, but this was only an instrumentation problem. A greater concern was that the front wheel steering would not work. However, the rear wheel steering was sufficient to maneuver the vehicle. Completing his checkout, Scott said "Okay. Out of detent; we're moving", maneuvering the rover away from "Falcon" in mid-sentence. These were the first words uttered by a human while driving a vehicle on the Moon. The rover carried a television camera, controlled remotely from Houston by NASA's Ed Fendell. The resolution was not high compared to the still photographs that would be taken, but the camera allowed the geologists on Earth to indirectly participate in Scott and Irwin's activities.
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The rille was not visible from the landing site, but as Scott and Irwin drove over the rolling terrain, it came into view. They were able to see Elbow crater, and they began to drive in that direction. Reaching Elbow, a known location, allowed Mission Control to backtrack and get closer to pinpointing the location of the lander. The astronauts took samples there, and then drove to another crater on the flank of Mons Hadley Delta, where they took more. After concluding this stop, they returned to the lander to drop off their samples and prepare to set up the Apollo Lunar Surface Experiments Package (ALSEP), the scientific instruments that would remain when they left. Scott had difficulty drilling the holes required for the heat flow experiment, and the work was not completed when they had to return to the lander. The first EVA lasted 6hours and 32 minutes.
Second and third EVAs.
The rover's front steering, inoperative during the first EVA, worked during the second and third ones. The target of the second EVA, on August 1, was the slope of Mons Hadley Delta, where the pair sampled boulders and craters along the Apennine Front. They spent an hour at Spur crater, during which the astronauts collected a sample dubbed the Genesis Rock. This rock, an anorthosite, is believed to be part of the early lunar crust—the hope of finding such a specimen had been one reason the Hadley area had been chosen. Once back at the landing site, Scott continued to try to drill holes for experiments at the ALSEP site, with which he had struggled the day before. After conducting soil-mechanics experiments and raising the U.S. flag, Scott and Irwin returned to the LM. EVA2 lasted 7hours and 12 minutes.
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