Scientific Exploration Detailed scientific exploration began with the flight of Apollo 12, Nov. 14-24, 1969. Comdr. Pete
Conrad, Jr., and Comdr. Alan L. Bean
landed (on Nov. 19) in the
Lunar Module Intrepid in Oceanus Procellarum (Ocean of Storms), while Comdr. Richard F. Gordon, Jr., cruised in orbit in the CSM Yankee Clipper. Conrad and Bean made two sorties of extravehicular activity (or EVA) on the surface, totaling 7 hours and 50 minutes. They unpacked the first Apollo Lunar Scientific Package (ALSEP), consisting of an array of scientific instruments, on the first EVA. On the second, they hiked almost a kilometer (a half mile) to inspect the Surveyor 3 spacecraft, and took 11 kg (25 lb) of its parts for analysis of the effect of the lunar environment on metal and glass. They brought back 33.9 kg (74.7 lb) of rocks and soil. Two days after Apollo 13 was launched on Apr. 11, 1970, an oxygen tank exploded in the Service Module and crippled the vessel's power and life-support systems so badly that a planned landing in the Fra Mauro formation of the Moon was canceled. Navy Capt. James A. Lovell, Jr., and civilians Fred W. Haise, Jr., and John L. Swigert, Jr., used the descent engine of the LM Aquarius to accelerate the crippled CSM Odyssey around the Moon and back to Earth. Using Aquarius as a lifeboat, they returned to the vicinity of Earth, entered the Command Module, and landed it safely on April 17. Investigation showed that a thermostatically controlled switch had failed and allowed the oxygen tank to overheat. Apollo 14 (Jan. 31-Feb. 9, 1971) reached the Fra Mauro uplands. Navy Capt. Alan B. Shepard, Jr., and Comdr. Edgar D. Mitchell landed in the LM Antares while Maj. Stuart A. Roosa cruised overhead in the CSM Kitty Hawk. After deploying ALSEP instruments, including a second laser reflector, Shepard and Mitchell towed a rickshalike, two-wheeled cart containing tools and instruments to the edge of a crater. They collected 42.9 kg (94.3 lb) of rocks and soil and spent 9 hours and 9 minutes outside on two EVAs. Quarantining returned lunar astronauts at Houston for 14 days after their departure from the Moon was terminated after this mission. Apollo 15 (July 26-Aug. 7, 1971) brought the first manned surface vehicleÑthe Lunar RoverÑto the Moon. It was carried with its wheels folded, in the descent stage of the LM Falcon. While Maj. Alfred M. Worden orbited the Moon in the CSM Endeavor, Col. David R. Scott and Lt. Col. James B. Irwin landed the Falcon on the Apennine mountain front, near the Hadley Rille. They spent 18.5 hours roaming for more than 30 km (18.6 mi) on the surface in the Rover, setting up experiments, taking measurements, and collecting 77 kg (170 lb) of soil and rocks. A subsatellite containing instruments for measuring gamma- and X-radiation from the surface was deployed in lunar orbit for the first time by Worden. The last two missions penetrated the lunar highlands. Apollo 16 (Apr. 16-27, 1972) was targeted for the Descartes highlands in the Southern Hemisphere. Navy Capt. John W. Young and Lt. Col. Charles M. Duke, Jr., landed April 20 in the LM Casper while Lt. Col. Thomas K. Mattingly II cruised in orbit in the CSM Orion. The explorers covered 27 km (16.8 mi) in their Rover and collected 95.8 kg (210.8 lb) of samples, in EVAs totaling 20 hours and 14 minutes. Apollo 17 (Dec. 7-19, 1972) took the first geologist, Harrison H. Schmitt, to the Moon. He and Navy Capt. Eugene A. Cernan landed in the Taurus Mountains, near the Littrow crater, on December 11, in the LM Challenger. Comdr. Ronald E. Evans made observations from orbit in the CSM America. Cernan and Schmitt spent 22 hours outside and brought back 110 kg (242 lb) of rocks and soil cores, having traversed 35 km (22 mi) in their Rover. This was the final mission in the Apollo lunar landing program.