"Added Mobility Spurs Lunar Harvest," Zack Strickland, Aviation Week & Space Technology, August 9, 1971, pp. 13-17; Astronautics and Aeronautics 1971, NASA SP 4016, pp. 205-206, 216, 217; Apollo 15 Preliminary Science Report, NASA SP 289, 1972, pp. 1.5-1.6; Apollo Lunar Surface Journal, Eric Jones, 1995 (http://www.hq.nasa.gov/office/pao/History/alsj/); A Man on the Moon, Andrew Chaikin, 1994, pp. 439-440; To a Rocky Moon, Donald Wilhelms, 1993, pp. 278.
August 5
1971 EVA 7
World EVA 22
U.S. EVA 20
Deep Space EVA 1
Duration: 0:41 Spacecraft/mission: Apollo 15 Crew: David Scott, James Irwin, Alfred Worden Spacewalker: Alfred Worden Purpose: Retrieve film from SIM bay of CM Endeavour
Alfred Worden became the first astronaut to "go EVA" beyond the protective envelope of Earth's inner magnetosphere. The planned 1-hr EVA, 273,600 km (171,000 mi) from Earth, was televised via a camera on a boom extended from the CM hatch. Using handrails and foot restraints, he had no difficulty making three round trips to the Scientific Instrument Module (SIM) bay built into the side of Endeavour's Service Module (SM). Irwin guided Worden's 8.3-m (27.4-ft) tether from CM hatch. Worden first retrieved the 39-kg (86-lb) Itek panoramic camera cassette, which he tethered to his arm and carried to Irwin at the hatch. Though Worden's metabolic rates remained acceptable throughout the EVA, CapCom Karl Henize warned him not to rush. On the second trip, he removed the 10-kg (22-lb) cassette from the Fairchild mapping camera. Worden made an unplanned third trip to inspect SIM bay instruments which had malfunctioned.
"Worden Takes First Deep Space Walks," Aviation Week & Space Technology, August 9, 1971, pp. 22-23.
1972
April 16
Apollo 16 launch
April 21
1972 EVA 1
World EVA 23
U.S. EVA 21
Lunar Surface EVA 10
Duration: 7:11 Spacecraft/mission: Apollo 16 Crew: John Young, Charles Duke, Thomas Mattingly Moonwalkers: John Young, Charles Duke Purpose: Deploy ALSEP; deploy LRV; geological traverse to Flag crater
Apollo 16, 1972—The LRV is clearly visible in this photograph of John Young taken by Charles Duke at Apollo 16's Descartes landing site. (AS16-117-18825)
Image
Apollo 16 was the only expedition planned to the lunar highlands. LM Orion landed several hours late because of a malfunction in CM Casper's Service Propulsion System. For a time Mission Control feared that the malfunction might prevent the CM from making rendezvous with the LM ascent stage after liftoff from the lunar surface. Mission Control delayed the first EVA's start until after an 8-hr rest period, during which Commander Young and LMP Duke studied the Descartes site through Orion's windows. They reported that Descartes was rockier and hillier than previous sites. Duke had trouble getting into his EMU because he had grown 4 cm (1.5 in) in weightlessness. This physiological effect of weightlessness was not taken into account during suit fitting in the Apollo program. A problem with Orion's steerable antenna delayed EVA start by 1 hr and prevented Young's first steps on the Moon from being televised. For the first time the astronauts collected no contingency sample. They deployed the U.S. flag, then began ALSEP deployment about 90 min into the EVA. Duke used an improved drill to collect a 2.6-m (8.6-ft) core. He inserted the heat flow probe, which was linked to the ALSEP central station by a cable. Young then accidentally walked over the cable, tearing it loose from the central station. Mission Control began study of a possible repair during the second EVA. The deployment lanyard on the cosmic ray experiment broke, leaving the crew uncertain as to whether the instrument was fully deployed. They then deployed the LRV from Orion's side. The rover had no rear steering and one of its batteries read low. However, rear steering returned and the battery read normal 40 min into the traverse. Young and Duke drove past Flag, Spook, Buster, and Plum craters. Near Plum they collected an 11.7-kg (25.7-lb) rock through a "videoconference" with Earth using the LRV camera. The LRV bounced a great deal during the traverses. Following the traverse, Duke operated a movie camera while Young performed LRV traction tests known jocularly as the "Grand Prix." When Mission Control relayed the news that the House of Representatives approved FY 1973 Space Shuttle funding the day before, John Young leaped 1 m (3 ft) and saluted the flag. (Young went on to command the first Shuttle mission, STS-1, in 1981.) Duke jumped too, but slipped and fell on his PLSS. After the EVA the astronauts reported the usual dust problems—stuck zippers and glove disconnects and indicators scratched and difficult to read.
Astronautics and Aeronautics 1972, NASA SP 4017, pp. 146, 155; Manned Spaceflight Log, Tim Furniss, 1983, p. 82; Apollo Lunar Surface Journal, Eric Jones, 1995 (http://www.hq.nasa.gov/ofce/pao/History/alsj/); Apollo 16 Preliminary Science Report, NASA SP 315, 1972, pp. 2.4-2.5, 6.6-6.7; To a Rocky Moon, Donald Wilhelms, 1993, pp. 295, 318; interview, David S. F. Portree with John Young, June 13, 1996.
April 22
1972 EVA 2
World EVA 24
U.S. EVA 22
Lunar Surface EVA 11
Duration: 7:23 Spacecraft/mission: Apollo 16 Crew: John Young, Charles Duke, Thomas Mattingly Moonwalkers: John Young, Charles Duke Purpose: Geological traverse to Stone Mountain
Prior to this second Apollo 16 EVA, Mission Control vetoed repair of the heat flow cable because it would take too much time and possibly short-circuit the ALSEP central station. Experimenters announced that they would strengthen the cable for the Apollo 17 mission. During egress a 5-cm portion of Young's PLSS antenna broke off against the LM's hatch frame, causing a small drop in signal strength. The astronauts moved the cosmic ray experiment to an LM footpad out of the Sun because it showed signs of overheating. Young noticed that he felt cooler in Orion's shadow, where the surface temperature was minus 84 deg C (minus 120 deg F). During the Apollo 16 EVAs surface temperature in the Sun was 88 deg C (190 deg F). Young and Duke then mounted the LRV and climbed Survey Ridge to Stone Mountain. A problem with LRV steering and traction was found to be caused by "mismatched power modes," and was solved by changing switch settings on the "dashboard" mounted ahead of the control T-handle. The astronauts collected core samples on Stone Mountain and reported that the view of their landing site was "just dazzling." The LM was barely visible in the distance. During descent to Orion the pitch meter on the dashboard pegged at 20 deg of slope. The astronauts collected a thin layer of surface material using adhesive plates. As with most Apollo lunar surface EVAs, some activities and stops were deleted because of insufficient time.
Astronautics and Aeronautics 1972, NASA SP 4017, pp. 146-147; Apollo 16 Preliminary Science Report, NASA SP 315, 1972, pp. 2.4-2.5, 5.2-5.3, 6.6-6.7; Apollo Lunar Surface Journal, Eric Jones, 1995 (http://www.hq.nasa.gov/office/pao/History/alsj/); To a Rocky Moon, Donald Wilhelms, 1993, p. 298; interview, David S. F. Portree with John Young, June 13, 1996.
April 23
1972 EVA 3
World EVA 25
U.S. EVA 23
Lunar Surface EVA 12
Duration: 5:40 Spacecraft/mission: Apollo 16 Crew: John Young, Charles Duke, Thomas Mattingly Moonwalkers: John Young, Charles Duke Purpose: Traverse to Smoky Mountain
The landing delay on April 21 caused more water than expected to be used in cooling Orion's avionics. Because the LM's cooling water supply was running low, consideration was given to deleting this third Apollo 16 EVA, a move the Apollo science "back room" at Mission Control vehemently opposed. The last Apollo 16 EVA began 30 min early, but overall length was cut by two hr and the traverse was shortened by five stops. Young and Duke drove to the foot of Smoky Mountain, near North Ray Crater, where they spent 1 hr, 20 min sampling and taking magnetic field readings using the Lunar Portable Magnetometer. They found the largest remnant magnetic field discovered on the Moon. The astronauts commented on the thick dust they kicked up and the generally shattered appearance of the area. Geologists in the back room asked Young to look at North Ray's bottom, but he turned down the request, saying that, "That rascally rim slopes about 10 or 15 degrees... then all of a sudden ... I've got to go 100 yards [92 m] down a 25 to 30 degree slope and I don't think I'd better." The astronauts collected samples off 10-m-high (33-ft-high), 20-m-long (66-ft-long) House Rock, the largest boulder sampled during Apollo. Young found that by hopping into the air and landing on his feet, the weight of his suit overcame the suit's internal pressure, so he could get to his knees and pick up rocks without using geological tools. The LRV suffered temporary navigational computer failure, but Young and Duke knew where they were from the Sun's position. They trended back toward their outbound tracks so they could follow them back to the LM, but spotted their spacecraft before they found their tracks. The LRV reached its highest speed on the Moon—22 kph (13 mph)—rolling down a 15-deg slope during return to Orion. Young left the LRV parked 50 m (164 ft) east of the LM, then helped Duke load 96.6 kg (212.5 lb) of lunar samples into the spacecraft. Controllers on Earth used the LRV camera to track Orion's ascent stage as it left Descartes behind. The LM's avionics cooling water ran out as it completed docking with the CM Casper.
Astronautics and Aeronautics 1972, NASA SP 4017, p. 148; Apollo 16 Preliminary Science Report, NASA SP 315, 1972, pp. 2.4-2.5, 5.2-5.3, 6.6-6.7; To a Rocky Moon, Donald Wilhelms, pp. 300-301; A Man on the Moon, Andrew Chaikin, 1994, pp. 488-489; interview, David S. F. Portree with John Young, June 13, 1996; Eric Jones, email, August 19, 1996.
April 25
1972 EVA 4
World EVA 26
U.S. EVA 24
Deep Space EVA 2
Duration: 1:24 Spacecraft/mission: Apollo 16 Crew: John Young, Charles Duke, Thomas Mattingly Spacewalker: Thomas Mattingly Purpose: Retrieve film from SIM bay of CM Casper
During the flight home moondust drifted around Casper's cabin. Some spilled into space when Mattingly stepped out to recover mapping and panoramic camera film from the SIM bay. Mattingly made two leisurely trips along Casper's Service Module. He inspected the spacecraft's exterior and exposed the Microbial Ecological Evaluation Device to space for 10 min. Before returning to the cabin, he opened his visor briefly so he could see the stars, taking care not to look in the direction of the Sun.
Astronautics and Aeronautics 1972, NASA SP 4017, p. 149; Apollo 16 Preliminary Science Report, NASA SP 315, 1972, p. 2.10; A Man on the Moon, Andrew Chaikin, 1994, p. 492.
April 27
Apollo 16 splashdown
December 7
Apollo 17 launch
December 11
1972 EVA 5
World EVA 27
U.S. EVA 25
Lunar Surface EVA 13
Duration: 7:12 Spacecraft/mission: Apollo 17 Crew: Eugene Cernan, Harrison Schmitt, Ronald Evans Moonwalkers: Eugene Cernan, Harrison Schmitt Purpose: Deploy LRV; deploy ALSEP; geological traverse south to Steno crater in Central Cluster
The first Apollo 17 surface EVA began 4 hr after landing with no television of Cernan's first step, the necessary TV equipment having been omitted to save weight and extend LM Challenger's hover time. Harrison Schmitt, the only geologist to visit the Moon, took a proprietary interest in the Taurus-Littrow site—he stepped onto the surface after Cernan and quipped, "Who's been tracking up my lunar surface?" The astronauts deployed and tested their LRV, then planted a U.S. flag which had hung in Mission Control since Apollo 11. Cernan accidentally knocked off part of one of the LRV's fenders and repaired it with tape. The astronauts set up the ALSEP 185 m (605 ft) northwest of the Challenger. Cernan drilled two holes 2.5 m (8.2 ft) deep 11 m (36 ft) apart and inserted two heat flow probes. He also drilled a core sample hole 2.8 m (9.2 ft) deep. Collecting the core required 1 hr—the core device stuck despite the long-handled jack designed to ease removal. Cernan's oxygen consumption climbed rapidly as his pulse hit 145 beats per min. Schmitt extracted the core by throwing his weight on the jack handle, but fell and scattered equipment. In general, the Apollo 17 astronauts treated their EMUs roughly—experience gained on earlier flights left them with little fear of suit damage. Cernan then inserted a cosmic-ray probe into the hole left by the core. Encumbered by his suit, Schmitt at first had trouble picking up rocks, which he admitted was "a very embarrassing thing for a geologist." The damaged LRV fender fell off on the way to the first geological survey station, so the astronauts were showered with dust. Schedule pressure forced deletion of a trek to Emory Crater in favor of a shorter trip to Steno Crater. The astronauts placed 0.45-kg (1-lb) and 0.23-kg (1/2-lb) explosive packages during the traverse. The explosives were set off after Cernan and Schmitt departed and recorded by geophones in the Apollo 17 ALSEP. Cernan drove so Schmitt could do science. The geologist carried a new long-handled scoop which allowed him to sample from the rover seat, saving time. Back at Challenger, Cernan reported that his tussle with the core tube bruised his arms and burst blood vessels under his fingernails. Dust tracked into the LM gave Schmitt a mild hayfever attack. However, dust catchers on the floor mitigated some of the dust difficulties experienced by previous crews.