HUMANSPACEFLIGHT

HUMAN SPACE FLIGHT

Within a year after the successes of the first small artificial satellites in 1957 and 1958, both the U.S. and the USSR were developing programs to place people in earth orbit. Both countries sent carefully monitored dogs and primates into orbit to study the effects of weightlessness on living creatures

Vostok and Mercury Programs

The USSR was the first to put a human into space when cosmonaut Yury A. Gagarin made one orbit of the earth in Vostok 1 on April 12, 1961. During his flight time of 1 hr 48 min he reached an apogee of 327 km (203 mi) and a perigee of 180 km (112 mi). He landed safely in Siberia. In the next two years five more Vostok flights were made. The pilot of Vostok 6 was Valentina V. Tereshkova, the first woman to fly in space. Launched on June 16, 1963, she orbited the earth 48 times.

Meanwhile, a similar U.S. program, called Mercury, was taking shape. On May 5, 1961, Comdr. Alan B. Shepard, Jr., of the U.S. Navy became the first American in space. The Mercury spacecraft, named Freedom 7, flew a ballistic trajectory and made a 15-min suborbital flight. A similar flight followed on July 21, flown by Capt. Virgil I. (Gus) Grissom (1926–67) of the U.S. Air Force. On Feb. 20, 1962, Lt. Col. John H. Glenn, Jr., of the U.S. Marine Corps, became the first U.S. astronaut to orbit the earth, in a flight of three orbits. Three additional Mercury flights were made in 1962 and 1963 by Lt. Col. M. Scott Carpenter (1925–    ) of the navy; Comdr. Walter (Wally) M. Schirra, Jr. (1923–    ), also of the navy; and Maj. Leroy Gordon Cooper, Jr. (1927–  ) of the air force.

Voskhod and Gemini Programs

The Russian Voskhod was an adaptation of the Vostok spacecraft modified to accommodate two and three cosmonauts. On Oct. 12, 1964, cosmonauts Vladimir M. Komarov (1927–67), Boris B. Yegorov (1937–    ), and Konstantin P. Feoktistov (1926–    ) made a 15-orbit flight in Voskhod 1. This was the only piloted flight that year and brought the total cumulative man-hours of Soviet cosmonauts in space to 455. The U.S. astronauts had a total then of 54 man-hours in space. On March 18, 1965, cosmonauts Pavel I. Belyayev (1925–70) and Aleksei A. Leonov (1934–    ) were launched in Voskhod 2. During this 17-orbit flight, Leonov made the first walk in space, or performed extravehicular activity (EVA), leaving the spacecraft and drifting out on an umbilical tether.

The U.S. Gemini program was designed to develop the technology required to go to the moon. In May 1961 U.S. President John F. Kennedy had instituted the Apollo program, designed to land a man on the moon and return him safely to the earth “before the decade is out.” This national commitment resulted in an intensive, large-scale, piloted flight program. The Gemini spacecraft carried two astronauts and was designed to operate for extended periods of time and to develop rendezvous and docking techniques with another orbiting spacecraft. Ten Gemini flights with human passengers were made in 1965–66.

During the Gemini 4 flight Maj. Edward H. White II (1930–67) of the air force became the first U.S. astronaut to perform EVA. Using a pressurized-gas, jet-maneuvering device, he spent 21 min in space. While Gemini 6 and 7 were in orbit together in December 1965, they rendezvoused within a few feet of each other. After orbiting for 20 hr, Gemini 6 with Schirra and Maj. Thomas P. Stafford (1930–    ) of the air force landed, and Gemini 7 with Lt. Col. Frank Borman (1928–    ) of the air force and Comdr. James A. Lovell, Jr. (1928–    ), of the navy went on to spend a total of 334 hr in orbit. This flight of nearly 14 days provided medical data on humans in space that was necessary to assure success of the 10-day Apollo lunar mission. Furthermore, it demonstrated the reliability of systems such as hydrogen-oxygen fuel-cell electric power and reaction controls. On the Gemini 10, 11, and 12 flights, rendezvous and docking were accomplished repeatedly with a target vehicle that had previously been orbited.

By the end of the last Gemini flight in November 1966, U.S. astronauts had accumulated nearly 2000 man-hours in space, which exceeded the Soviet cosmonaut total, and about 12 hr in EVA.

Soyuz and Apollo

The year 1967 was one of tragedy for both space-faring nations. On January 27, during a ground test of the Apollo spacecraft at Cape Kennedy (now Cape Canaveral), fire broke out in the three-man command module (CM). Because of the pressurized pure-oxygen atmosphere inside the spacecraft, a flash fire engulfed and killed the three astronauts—Grissom, White, and Lt. Comdr. Roger B. Chaffee (1935–67) of the navy. As a result of this tragedy, the Apollo program was delayed more than a year for a major review of vehicle design and materials.

On April 23, 1967, cosmonaut Komarov was launched in the first manned flight of a new Soviet spacecraft, Soyuz. The Soyuz had room for three cosmonauts and a separate working compartment, accessible through a hatch, for experiments. Following reentry into the earth’s atmosphere and deployment of landing parachutes, the shroud lines became twisted, and Komarov plunged to his death. The Soviet space program was set back nearly two years.

In October 1968 the first manned Apollo flight was launched by a Saturn 1B booster. Astronauts Schirra, Maj. R. Walter Cunningham (1932–    ) of the U.S. Marine Reserve Corps, and Maj. Donn F. Eisele (1930–87) of the air force circled the earth for 163 orbits, checking spacecraft performance, photographing the earth, and transmitting television pictures. In December 1968 Apollo 8, a landmark flight carrying astronauts Borman, Lovell, and Maj. William A. Anders (1933–    ) of the air force, circled the moon 10 times and returned to earth safely. The Apollo 9 flight, with Maj. James A. McDivitt (1929–    ) and Col. David R. Scott (1932–    ) of the air force and civilian Russell L. Schweickart (1935–    ), checked out undocking, rendezvous, and docking of the Apollo lunar module (LM) landing craft during a 151-orbit mission. The Apollo 10 flight, with astronauts Stafford and Lt. Comdr. John W. Young (1930–    ) and Comdr. Eugene A. Cernan (1934–    ) of the navy, made 31 orbits of the moon in a rehearsal for the lunar landing. As planned, Stafford and Cernan transferred from the Apollo CM to the LM, separated, and descended to within 16 km (10 mi) of the lunar surface while astronaut Young piloted the CM. Subsequently, rendezvous and docking of the ascent stage of the LM was accomplished; the two astronauts then transferred to the CM, discarded the LM, fired the service module rocket for return trajectory to earth, and returned safely. Project Apollo was now ready to land astronauts on the moon (see Human Lunar Exploration below).

Meanwhile, the USSR launched automated Zond spacecraft around the moon, carrying cameras and biological specimens. Col. Georgi T. Beregovoi (1921–95) flew a 60-orbit mission in Soyuz 3 in October 1968. Soyuz 4 and 5 rendezvoused and docked in earth orbit in January 1969. While the spacecraft were linked, cosmonauts Aleksei S. Yeliseyev (1934–    ) and Lt. Col. Yevgeny V. Khrunov (1933–2000), in space suits, transferred by EVA from Soyuz 5 to Soyuz 4, which was piloted by Col. Vladimir A. Shatalov (1927–    ). In October 1969 Soyuz 6, 7, and 8, each launched a day apart, rendezvoused in orbit but did not dock. Soyuz 9, with a two-cosmonaut crew, set a flight duration record of almost 18 days in June 1970.

Human Lunar Exploration

In 1969 humans achieved the long-awaited goal of actually landing on the moon.

Apollo 11

The historic flight of Apollo 11 was launched on July 16. After entering lunar orbit, astronauts Edwin E. (Buzz) Aldrin, Jr., of the air force and Neil A. Armstrong transferred to the lunar module (LM). Armstrong, a civilian, was a navy veteran. Lt. Col. Michael Collins of the air force remained in lunar orbit following the separation, piloting the command and service module. The LM descended to the surface of the moon on July 20, landing at the edge of Mare Tranquilitatis. A few hours later, Armstrong, in his bulky space suit, descended the ladder and, at 10:56 pm (Eastern Daylight Time) stepped onto the surface of the moon. His first words were, “That’s one small step for a man, one giant leap for mankind.” He was soon joined by Aldrin, and the two astronauts spent more than two hours walking on the lunar surface. They gathered 21 kg (47 lb) of soil samples, took photographs, and set up a solar wind experiment, a laser-beam reflector, and a seismic experiment package. Armstrong and Aldrin also erected an American flag and talked, by satellite communications, with U.S. President Richard M. Nixon in the White House. They found that walking and running at one-sixth the gravity of earth was not difficult. Also by satellite communications, millions of people watched live television broadcasts from the moon. Returning to the LM and discarding their space suits, the two astronauts rested several hours before takeoff. They left the moon in the ascent stage of the LM, using the lower half of the module, which remained on the moon, as a launchpad. The ascent stage was jettisoned after docking with the command and service module and the transfer of the astronauts to the spacecraft. The return flight of Apollo 11 to the earth was completed without mishap, and the vehicle splashed down and was recovered on July 24 in the Pacific Ocean near Hawaii.

Because of the slight possibility of terrestrial contamination by living lunar organisms, the astronauts put on “biological isolation garments” before leaving the spacecraft and were placed under quarantine for three weeks. They remained in good health.

The Apollo 11 flight attracted great interest around the world. The general feeling was that the lunar landing signaled a first step on a new plateau of evolution.

Apollo 12

The next moon-landing flight began on Nov. 14, 1969, when Apollo 12 was launched with astronauts Charles Conrad, Jr. (1930–99), Richard F. Gordon, Jr. (1929–    ), and Alan L. Bean (1932–    ), all of the navy, aboard. After entering lunar orbit, command pilot Conrad and Bean, the pilot of the LM, transferred to the LM. They landed north of the Riphaeus Mountains, at a spot just 180 m (600 ft) from where the Surveyor 3 spacecraft had landed two years before.

The two astronauts explored their surroundings during two periods, each lasting nearly four hours. They set up scientific experiments, took photographs, collected samples of lunar soil, and removed pieces from Surveyor 3 to be examined on their return to earth. After takeoff from the moon and rendezvous with the CM piloted by Gordon, successful splashdown and recovery took place on November 24. Quarantine procedures were repeated but, as with the Apollo 11 crew, the astronauts emerged in good health on December 10.

Apollo 12 demonstrated many improvements over Apollo 11 techniques, particularly in the accuracy of landing guidance. So successful were these changes that Apollo 13 was intended to land on more rugged terrain on the moon.

Apollo 13

On April 11, 1970, Apollo 13, carrying veteran astronaut Lovell and the civilian astronauts Fred W. Haise, Jr. (1933–    ), and John L. Swigert, Jr. (1931–82), was launched. The spacecraft encountered difficulties during the flight when an oxygen tank ruptured. As a result the astronauts were obliged to cancel their planned landing on the lunar surface. Instead, using the power and survival systems of the LM, the astronauts swung behind the moon and were then brought back to earth by the navigating technology of the mission control center in Houston, Tex., for a splashdown south of Pago Pago in the South Pacific Ocean on April 17.

Apollo 14 and 15

The mission of the aborted Apollo 13 was accomplished by the crew of Apollo 14, launched on Jan. 31, 1971, after modifications were carried out in the spacecraft to prevent the malfunctions encountered by Apollo 13. Capt. Shepard, who had been promoted after his successful suborbital flight in 1961 (see Vostok and Mercury Programs above), and Comdr. Edgar D. Mitchell (1930–    ), also of the navy, successfully landed the LM in the rugged Fra Mauro region of the moon, while astronaut Stuart A. Roosa (1933–94) of the air force remained in lunar orbit in the CM. Shepard and Mitchell spent more than 9 hr exploring an area that was believed to contain some of the oldest rocks yet recovered, collecting about 43 kg (95 lb) of geological samples and deploying scientific instruments. The astronauts returned to earth without incident on Feb. 9, 1971.

Apollo 15 was launched on July 26, 1971, with Col. Scott as flight commander, Lt. Col. James B. Irwin (1930–91) as pilot of the LM, and Maj. Alfred M. Worden (1932–    ) as pilot of the CM, all officers of the air force. Scott and Irwin spent 2 days 18 hr on the lunar surface at the edge of Mare Imbrium, close to the 366-m (1200-ft) deep Hadley Rille and the Apennine mountain range, one of the highest on the moon. During their 18 hr 37 min exploration of the lunar surface, the astronauts traversed more than 28.2 km (17.5 mi) in the vicinity of Mount Hadley in an electrically propelled four-wheeled “lunar rover.” They also deployed an elaborate package of scientific instruments and collected about 91 kg (about 200 lb) of rocks, including what was believed to be a sample of anorthosite, a crystalline piece of the original lunar crust, about 4.6 billion years old. A television camera left on the moon photographed Scott and Irwin’s departure from the surface, and before the crew left the lunar orbit for their return to earth, they launched into lunar orbit a 35.6-kg (78.5-lb) “subsatellite” designed to transmit data about gravitational, magnetic, and high-energy fields in the lunar environment. On the return journey, Worden made a 16-min walk in deep space while the spacecraft was about 315,400 km (196,000 mi) from the earth, a record distance. The Apollo 15 astronauts splashed down without incident on August 7, about 530 km (about 330 mi) north of Hawaii, and were the first moon-landing crew that was not required to undergo a quarantine.

Apollo 16 and 17

On April 16, 1972, astronauts Young, Charles Moss Duke, Jr. (1935–    ), and Thomas Kenneth (Ken) Mattingly (1936–    ) were launched on the Apollo 16 mission to the moon, to explore the Descartes Highlands and the Cayley Plains regions. While Mattingly remained in orbit, the two other astronauts landed in the assigned area on April 20. They spent 20 hr 14 min on the moon, setting up a number of experiments powered by a small nuclear station, traveling about 26.6 km (about 16.5 mi) in the lunar rover, and collecting more than 97 kg (214 lb) of rock samples.

The Apollo series missions to the moon concluded with the flight of Apollo 17, Dec. 6–19, 1972. During their smooth 13-day voyage, veteran astronaut Cernan and the American civilian geologist Harrison H. Schmitt (1935–    ) spent 22 hr on the moon, traveling 35 km (22 mi) in the lunar rover and exploring the Taurus-Littrow Valley region, while Comdr. Ronald E. Evans (1933–90) of the navy remained in lunar orbit.