KApollo 15, 16, and 17 Apollo 15 was the first of three extended scientific explorations of the moon using the LRV, the extended-duration PLSS, more mobile space suits, and more highly trained crews. These last three missions established the first lunar bases on the moon. Launched on July 26, 1971, the crew of David Randolph Scott, Alfred M. Worden, and James A. Irwin flew the spacecraft Endeavour (CSM) and Falcon (LM). On July 30, 1971 Scott and Irwin landed the LM on the western edge of the Apennine mountains, and, during the nearly three days they spent on the moon, the crew conducted four explorations outside their home base, called Hadley Base. They traveled a total distance of 27.9 km (17.3 mi) on the LRV, ranging up to 4.9 km (3.0 mi) from the LM, and moving over the horizon and out of view of their home base for the first time. They set into place an ALSEP scientific station, made extensive geological observations and interpretations, and collected a total of 77 kg (170 lb) of lunar rocks and soil. This 12-day mission landed safely in the Pacific Ocean.
Apollo 16 was launched on April 16, 1972. The crew of John W. Young, T. Kenneth Mattingly, and Charles Moss Duke, Jr., flew the spacecraft Casper (CSM) and Orion (LM). On April 20, 1972, Young and Duke landed the LM near Descartes Crater and during the nearly three days they spent on the moon, the crew collected a total of 94 kg (207 lb) of lunar rocks and soil. They traveled a total distance of 27 km (17 mi) on the LRV, ranging up to 4.5 km (2.8 mi) from Descartes Base. This 11-day mission landed and was recovered in the Pacific Ocean on April 27, 1972.
Apollo 17 was the third extended scientific exploration of the moon and the final mission of the formal Apollo program. Launched on December 7, 1972, the crew of Eugene Andrew Cernan, Ronald Elwin Evans, and Harrison Hagan Schmitt flew the spacecraft America (CSM) and Challenger (LM). On December 11, 1972, Cernan and Schmitt landed the LM in the Taurus Littrow Valley region of the moon. During the more than three days they spent on the moon, the crew traveled a total distance of 35.0 km (22 mi) on the LRV, ranging up to 7.8 km (4.8 mi) from Taurus Base. They collected a total of 110 kg (240 lb) of lunar rocks and soil. This 12-day mission landed in the Pacific Ocean.
IVMISSIONS TO SKYLAB The Skylab space station project originated in the 1960s to demonstrate that humans could live and work in space for extended periods and to expand the knowledge of solar astronomy. The Skylab station was launched unmanned on May 14, 1973. It was placed into a near-circular earth orbit at an altitude of 430 km (270 mi). However, it was damaged during launch when one of two solar panel wings was ripped off.
On May 25, 1973, the first three-man crew to occupy Skylab was launched aboard an Apollo CSM. The crew of Pete Conrad, Paul Weitz, and Joseph Kerwin conducted an extensive EVA to repair the damaged Skylab station and carried out experiments in orbit for 28 days, after which they reentered the atmosphere in the command module.
A second mission to Skylab, with a crew of Alan LaVern Bean, Owen Garriott, and Jack Robert Lousma, was launched on July 28, 1973. They occupied the station for 59 days. The final mission to Skylab, with Gerald Carr, Edward Gibson, and William Pogue, was launched on November 16, 1973. These astronauts occupied the station for a record 84 days. Each Skylab crew set a manned spaceflight endurance record, and all of the objectives of the Skylab program were accomplished. The Skylab station decayed in orbit and reentered the atmosphere over the Indian Ocean on July 11, 1979.
VAPOLLO-SOYUZ TEST PROJECT The primary objective of the Apollo-Soyuz Test Project (ASTP) in the mid-1970s was to conduct a joint diplomatic mission with the Soviet Union. ASTP was designed to test the compatibility of U.S. and Soviet spacecraft and rendezvous and docking systems as a prelude to international space rescue, as well as future international space missions.
The ASTP mission was planned and conducted using existing Apollo and Soviet Soyuz spacecraft as well as launch vehicles and operational techniques. The only new technologies used were a universal docking system and docking module designed and constructed by NASA to serve as the connection and airlock transfer tunnel between the two spacecraft.
On July 15, 1975, the Soyuz 19 spacecraft and its crew of Alexei Leonov and Valerei Kubasov were launched from the Baikonur Cosmodrome in Kazakhstan. Precisely 7 hours and 30 minutes later, the final Apollo CSM, with its crew of Thomas P. Stafford, Deke Slayton, and Vance DeVoe Brand, was launched from Cape Canaveral.
After a flawless rendezvous, the Apollo spacecraft and Soyuz 19 docked-45 hours and 22 minutes after Apollo liftoff. After stabilizing the systems of the spacecraft and the docking module, the first international handshake in space occurred when Tom Stafford and Alexei Leonov met at the edge of the open docking tunnel.
The two spacecraft remained together for over 47 hours, during which a brief separation and redocking were conducted to further demonstrate the operations and compatibility of the docking system. Approximately 43 hours after final separation, Soyuz 19 completed its mission and reentered to a precision landing in central Russia on July 21, 1975.
The Apollo spacecraft remained in space for an additional six days to conduct experiments. The craft reentered the earth’s atmosphere for a landing in the Pacific Ocean on July 24, 1975.
VIAPOLLO ACHIEVEMENTS The Apollo program demonstrated effective human geological exploration in the hostile environment of another planet. During the initial Apollo 11 lunar landing mission, the crew remained on the moon for less than one day and conducted a single excursion of less than three hours, during which they ventured only 50 m (160 ft) from the LM. By the sixth and final lunar exploration mission, the distance traveled on the lunar surface had greatly increased. By the last mission to the moon, Apollo crews had traversed a total distance of more than 97 km (60 mi) on the lunar surface and spent over 160 man-hours outside the LM.
A broad range of over 60 scientific experiments were performed on the lunar surface, and 30 experiments were conducted from lunar orbit. Six long-term scientific stations were manually placed and activated on the moon by the astronauts. The last four operating stations (set up by Apollos 12 and 15 through 17) were finally turned off by NASA in 1977.
The experiments carried out on the Apollo missions provided important information about the moon as well as the solar system. A total of 381.7 kg (841 lb) of lunar material was returned from six unique and scientifically significant lunar locations. Additionally, almost 30,000 high-resolution photographs were taken on the surface and from orbit during Apollo missions, recording the characteristics and features of the moon in great detail.