space exploration the investigation of physical conditions in space and on stars, planets, and other celestial bodies through the use of artificial satellites (spacecraft that orbit the earth), space probes (spacecraft that pass through the solar system and that may or may not orbit another celestial body), and spacecraft with human crews.

Satellites and Probes

Although studies from earth using optical and radio telescopes had accumulated much data on the nature of celestial bodies, it was not until after World War II that the development of powerful rockets made direct space exploration a technological possibility. The first artificial satellite, Sputnik I, was launched by the USSR (now Russia) on Oct. 4, 1957, and spurred the dormant U.S. program into action, leading to an international competition popularly known as the "space race."Explorer I, the first American satellite, was launched on Jan. 31, 1958. Although earth-orbiting satellites have by far accounted for the great majority of launches in the space program, even more information on the moon, other planets, and the sun has been acquired by space probes.

Lunar Probes

In the decade following Sputnik I, the United States and the USSR between them launched about 50 space probes to explore the moon . The first probes were intended either to pass very close to the moon (flyby) or to crash into it (hard landing). Later probes made soft landings with instruments intact and achieved stable orbits around the moon. Each of these four objectives required increasingly greater rocket power and more precise maneuvering; successive launches in the Soviet Luna series were the first to accomplish each objective. Luna 2 made a hard lunar landing in Sept., 1959, and Luna 3 took pictures of the moon's far side as the probe flew by in Nov., 1959. Luna 9 soft-landed in Feb., 1966, and Luna 10 orbited the moon in Apr., 1966; both sent back many television pictures to earth. In addition to the 24 lunar probes in the Luna program, the Soviets also launched five circumlunar probes in its Zond program.

Early American successes generally lagged behind Soviet accomplishments by several months but provided more detailed scientific information. The U.S. program did not bear fruit until 1964, when Rangers 7,8, and 9 transmitted thousands of pictures, many taken at altitudes of less than 1 mi (1.6 km) just before impact and showing craters only a few feet in diameter. Two years later, the Surveyor series began a program of soft landings on the moon. Surveyor 1 touched down in June, 1966; in addition to television cameras, it carried instruments to measure soil strength and composition. The Surveyor program established that the moon's surface was solid enough to support a spacecraft carrying astronauts.

In Aug., 1966, the United States successfully launched the first Lunar Orbiter, which took pictures of both sides of the moon as well as the first pictures of the earth from the moon's vicinity. The Orbiter's primary mission was to locate suitable landing sites for the Apollo Lunar Module, but in the process it also discovered the lunar mascons, regions of large concentration of mass on the moon's surface. Between May, 1966, and Nov., 1968, the United States launched seven Surveyors and five Lunar Orbiters. Clementine, launched in 1994, engaged in a systematic mapping of the lunar surface. In 1998, Lunar Prospector orbited the moon in a low polar orbit investigating possible polar ice deposits, but a controlled crash near the south pole detected no water. China became the third nation to send a spacecraft to the moon when Chang'e 1, which was launched in 2007, crash-landed on the lunar surface in 2009. The U.S. Lunar Reconnaissance Orbiter, launched in 2009, was designed to collect data that can be used to prepare for future missions to the moon; information from it has been used to produce a relatively detailed, nearly complete topographic map of the moon.

Interplanetary Probes

While the bulk of space exploration initially was directed at the earth-moon system, the focus gradually shifted to other members of the solar system. The U.S. Mariner program studied Venus and Mars, the two planets closest to the earth; the Soviet Venera series also studied Venus. From 1962 to 1971, these probes confirmed the high surface temperature and thick atmosphere of Venus, discovered signs of recent volcanism and possible water erosion on Mars, and investigated Mercury. Between 1971 and 1973 the Soviet Union launched six successful probes as part of its Mars program. Exploration of Mars continued with the U.S. Viking landings on the Martian surface. Two Viking spacecraft arrived on Mars in 1976. Their mechanical arms scooped up soil samples for automated tests that searched for photosynthesis, respiration, and metabolism by any microorganisms that might be present; one test suggested at least the possibility of organic activity. The Soviet Phobos 1 and 2 missions were unsuccessful in 1988. The U.S. Magellan spacecraft succeeded in orbiting Venus in 1990, returning a complete radar map of the planet's hidden surface. The Japanese probes Sakigake and Suisei and the European Space Agency's probe Giotto both rendezvoused with Halley's comet in 1986, and Giotto also came within 125 mi (200 km) of the nucleus of the comet Grigg-Skjellerup in 1992. The U.S. probe Ulysses returned data about the poles of the sun in 1994, and the ESA Solar and Heliospheric Observatory ( SOHO ) was put into orbit in 1995. Launched in 1996 to study asteroids and comets, the Near Earth Asteroid Rendezvous ( NEAR ) probe made flybys of the asteroids Mathilde (1997) and Eros (1999) and began orbiting the latter in 2000. The Mars Pathfinder and Mars Global Surveyor, both of which reached Mars in 1997, were highly successful, the former in analyzing the Martian surface and the latter in mapping it. The ESA Mars Express, launched in 2003, began orbiting Mars later that year, and although its Beagle 2 lander failed to establish contact, the orbiter has sent back data. Spirit and Opportunity, NASA rovers, landed successfully on Mars in 2004. Messenger, also launched by NASA, became the first space probe to orbit Mercury in 2011.

Space probes have also been aimed at the outer planets, with spectacular results. One such probe, Pioneer 10, passed through the asteroid belt in 1973, then became the first object made by human beings to escape the solar system. In 1974, Pioneer 11 photographed Jupiter's equatorial latitudes and its moons, and in 1979 it made the first direct observations of Saturn. Voyagers 1 and 2, which were launched in 1977, took advantage of a rare alignment of Jupiter, Saturn, Uranus, and Neptune to explore all four planets. Passing as close as 3,000 mi (4,800 km) to each planet's surface, the Voyagers discovered new rings, explored complex magnetic fields, and returned detailed photographs of the outer planets and their unique moons. They have since moved toward the heliopause, the boundary between the influence of the sun's magnetic field and the interstellar magnetic field. Launched in 1989, the Galileo spacecraft followed a circuitous route that enabled it to return data about Venus (1990), the moon (1992), and the asteroids 951 Gaspra (1991) and 243 Ida (1993) before it orbited Jupiter (1995–2003); it also returned data about the Jupiter's atmosphere and its largest moons (Io, Ganymede, Europa, and Callisto). The joint U.S.-ESA Cassini mission, launched in 1997, began exploring Saturn, its rings, and some of its moons upon arriving in 2004. It deployed Huygens, which landed on the surface of Saturn's moom Titan in early 2005.

Human Space Exploration

Human spaceflight has progressed from the simple to the complex, starting with suborbital flights; subsequent highlights included the launching of a single astronaut in orbit, the launching of several astronauts in a single capsule, the rendezvous and docking of two spacecraft, the attainment of lunar orbit, and the televised landing of an astronaut on the moon. The first person in earth orbit was a Soviet cosmonaut, Yuri Gagarin , in Vostok 1 on Apr. 12, 1961. The American Mercury program had its first orbital success in Feb., 1962, when John Glenn circled the earth three times; a flight of 22 orbits was achieved by Mercury in May, 1963. In Oct., 1964, three Soviet cosmonauts were launched in a Voskhod spacecraft. During the second Voskhod flight in Mar., 1965, a cosmonaut left the capsule to make the first "walk in space."

The first launch of the Gemini program, carrying two American astronauts, occurred a few days after the Soviet spacewalk. The United States made its first spacewalk during Gemini 4, and subsequent flights established techniques for rendezvous and docking in space. The first actual docking of two craft in space was achieved in Mar., 1966, when Gemini 8 docked with a crewless vehicle. In Oct., 1967, two Soviet Cosmos spacecraft performed the first automatic crewless rendezvous and docking. Gemini and Voskhod were followed by the American Apollo and the Soviet Soyuz programs, respectively.

The Apollo Program

In 1961, President Kennedy had committed the United States to the goal of landing astronauts on the moon and bringing them safely back to earth by the end of the decade. The resulting Apollo program was the largest scientific and technological undertaking in history. Apollo 8 was the first craft to orbit both the earth and the moon (Dec., 1968); on July 20, 1969, astronauts Neil A. Armstrong and Edwin E. ( "Buzz" ) Aldrin , Jr., stepped out onto the moon, while a third astronaut, Michael Collins, orbited the moon in the command ship. In all, there were 17 Apollo missions and 6 lunar landings (1969–72). Apollo 15 marked the first use of the Lunar Rover, a jeeplike vehicle. The scientific mission of Apollo centered around an automated geophysical laboratory, ALSEP (Apollo Lunar Surface Experimental Package). Much was learned about the physical constitution and early history of the moon, including information about magnetic fields, heat flow, volcanism, and seismic activity. The total lunar rock sample returned to earth weighed nearly 900 lb (400 kg).

Apollo moon flights were launched by the three-stage Saturn V rocket, which developed 7.5 million lb (3.4 million kg) of thrust at liftoff. At launch, the total assembly stood 363 ft (110 m) high and weighed more than 3,000 tons. The Apollo spacecraft itself weighed 44 tons and stood nearly 60 ft (20 m) high. It was composed of three sections: the command, service, and lunar modules. In earth orbit, the lunar module (LM) was freed from its protective compartment and docked to the nose of the command module. Once in lunar orbit, two astronauts transferred to the LM, which then detached from the command module and descended to the lunar surface. After lunar exploration, the descent stage of the LM remained on the moon, while the ascent stage was jettisoned after returning the astronauts to the command module. The service module was jettisoned just before reentering the earth's atmosphere. Thus, of the huge craft that left the earth, only the cone-shaped command module returned.

The Soyuz Program

Until late 1969 it appeared that the USSR was also working toward landing cosmonauts on the moon. In Nov., 1968, a Soviet cosmonaut in Soyuz 3 participated in an automated rendezvous and manual approach sequence with the crewless Soyuz 2.Soyuz 4 and 5 docked in space in Jan., 1969, and two cosmonauts transferred from Soyuz 5 to Soyuz 4 ; it was the first transfer of crew members in space from separately launched vehicles. But in July, 1969, the rocket that was to power the lunar mission exploded, destroying an entire launch complex, and the USSR abandoned the goal of human lunar exploration to concentrate on orbital flights. The program suffered a further setback in June, 1971, when Soyuz 11 accidentally depressurized during reentry, killing all three cosmonauts. In July, 1975, the United States and the USSR carried out the first internationally crewed spaceflight, when an Apollo and a Soyuz spacecraft docked while in earth orbit. Later Soyuz spacecraft have been used to ferry cosmonauts to and from Salyut and Mir.

Space Stations

After the geophysical exploration of the moon via the Apollo program was completed, the United States continued human space exploration with Skylab, an earth-orbiting space station that served as workshop and living quarters for three astronauts. The main capsule was launched by a booster; the crews arrived later in an Apollo-type craft that docked to the main capsule. Skylab had an operational lifetime of eight months, during which three three-astronaut crews remained in the space station for periods of about one month, two months, and three months. The first crew reached Skylab in May, 1972.

Skylab 's scientific mission alternated between predominantly solar astrophysical research and study of the earth's natural resources; in addition, the crews evaluated their response to prolonged conditions of weightlessness. The solar observatory contained eight high-resolution telescopes, each designed to study a different part of the spectrum (e.g., visible, ultraviolet, X-ray, or infrared light). Particular attention was given to the study of solar flares (see sun ). The earth applications, which involved remote sensing of natural resources, relied on visible and infrared light in a technique called multispectral scanning (see space science ). The data collected helped scientists to forecast crop and timber yields, locate potentially productive land, detect insect infestation, map deserts, measure snow and ice cover, locate mineral deposits, trace marine and wildlife migrations, and detect the dispersal patterns of air and water pollution. In addition, radar studies yielded information about the surface roughness and electrical properties of the sea on a global basis. Skylab fell out of orbit in July, 1979; despite diligent efforts, several large pieces of debris fell on land.

After that time the only continuing presence of humans in earth orbit were the Soviet Salyut and Mir space stations, in which cosmonauts worked for periods ranging to more than 14 months. In addition to conducting remote sensing and gathering medical data, cosmonauts used their microgravity environment to produce electronic and medical artifacts impossible to create on earth. In preparation for the International Space Station (ISS)—a cooperative program of the United States, Russia, Japan, Canada, Brazil, and the ESA—astronauts and cosmonauts from Afghanistan, Austria, Britain, Bulgaria, France, Germany, Japan, Kazakhstan, Syria, and the United States worked on Mir alongside their Russian counterparts. Assembly of the ISS began in Dec., 1998, with the linking of an American and a Russian module (see space station ) Once the ISS was manned in 2000, maintaining Mir in orbit was no longer necessary and it was made to decay out of orbit in Mar., 2001.

The Space Shuttle

After the Skylab space station fell out of orbit in 1979, the United States did not resume sending astronauts into space until 1981, when the space shuttle , capable of ferrying people and equipment into orbit and back to earth, was launched. The shuttle itself was a hypersonic delta-wing airplane about the size of a DC-9. Takeoff was powered by three liquid-fuel engines fed from an external tank and two solid-fuel engines; the last were recovered by parachute. The shuttle itself returned to earth in a controlled glide, landing either in California or in Florida.

The shuttle put a payload of up to 25 tons (22,700 kg) in earth orbit below 600 mi (970 km); the payload was then boosted into final orbit by its own attached rocket. The Galileo probe, designed to investigate Jupiter's upper atmosphere, was launched from the space shuttle. Astronauts also used the shuttle to retrieve and repair satellites, to experiment with construction techniques needed for a permanent space station, and to conduct scientific experiments during extended periods in space.

At first it was hoped that shuttle flights could operate on a monthly basis, but schedule pressures contributed to the explosion of the Challenger shuttle in 1986, when cold launch conditions led to the failure of a rubber O-ring, and the resulting flame ruptured the main fuel tank. The shuttle program was suspended for three years, while the entire system was redesigned. The shuttle fleet subsequently operated on approximately a bimonthly schedule. A second accident occurred in 2003, when Columbia was lost during reentry because damaged heat shielding on the left wing, which had been damaged by insulation shed from the external fuel tank, failed to prevent superheated gas from entering the wing; the hot gas structurally weakened the wing and caused the shuttle to break up. Shuttle flights resumed in July, 2005, but new problems with fuel tank insulation led NASA to suspend shuttle launches for a year. The last shuttle flight was in July, 2011. In 2004, President George W. Bush called for a return to the moon by 2020 and the establishment of a base there that would be used to support the human exploration of Mars. The following year NASA unveiled a $104 billion plan for a lunar expedition that resembled that Apollo program in many respects, except that two rockets would be used to launch the crew and lunar lander separately.

In June, 2004, SpaceShipOne, a privately financed spacecraft utilizing a reusable vehicle somewhat similar in concept to the shuttle, was launched into suborbital flight from the Mojave Desert in California. Unlike the shuttle, SpaceShipOne is carried aloft by a reusable jet mothership (White Knight) to 46,000 ft (13.8 km), where it is released and fires its rocket engine. The spacecraft was designed by Bert Rutan and built by his company, Scaled Composites. The vehicle's 90-minute flight was the first successful nongovernmental spaceflight. Another spacecraft is being privately developed by Space Exploration Technologies, or SpaceX, in coordination with NASA. The company's Falcon 9 rocket had its first successful launch, from Cape Canaveral, in June, 2010. In Dec., 2010, SpaceX launched the Dragon space capsule, using a Falcon 9 rocket, and successfully returned the capsule to earth after almost two orbits. The Dragon is intended to be used to resupply the space station.

The Chinese Space Program

China launched its first satellite in 1970 and then began the Shuguang program to put an astronaut into space, but the program was twice halted, ending in 1980. In the 1990s, however, China began a new program, and launched the crewless Shenzhou 1, based on the Soyuz, in 1999. The Shenzhou, like the Soyuz, is capable of carrying a crew of three. In Oct., 2003, Shenzhou 5 carried a single astronaut, Yang Liwei, on a 21-hr, 14-orbit flight, making China only the third nation to place a person in orbit. A second mission, involving two astronauts, occurred in Oct., 2005. China also launched an unmanned moon mission in Oct., 2007.

Bibliography

See T. Wolfe, The Right Stuff (repr. 1983); B. C. Murray, Journey into Space (repr. 1990); V. Neal, Where Next, Columbus?: The Future of Space Exploration (1994); J. Harford, Korolev: How One Man Masterminded the Soviet Drive to Beat America to the Moon (1997); T. A. Heppenheimer, Countdown: A History of Space Flight (1997); F. J. Hale, Introduction to Space Flight (1998); R. D. Launius, Frontiers of Space Exploration (1998); C. Nelson, Rocket Men: The Epic Story of the First Men on the Moon (2009); A. Chaikin with V. Kohl, Voices from the Moon (2009).

Space Exploration

SOCIAL ORIGINS

SOCIETAL IMPLICATIONS

BIBLIOGRAPHY

The sociocultural status of space exploration has been contested for many years and remains uncertain. Although astronomy and related sciences have benefited greatly from the world’s space programs, space exploration was motivated not by scientific curiosity but by the romanticism of a social movement and by competition between prestige-conscious nations. By the end of the nineteenth century, astronomy possessed a rough picture of the solar system, including the knowledge that objects like the Moon and Mars were worlds somewhat comparable to the earth, but realistic means for space travel had not yet been imagined. Then, autonomous intellectuals independently developed the correct theories for multistage liquid-fuel rockets.

SOCIAL ORIGINS

Konstantin Tsiolkovsky (1857–1935) was an impoverished schoolteacher in Russia who devoted many years of socially isolated work to developing fruitful ideas about spaceflight. American Robert H. Goddard (1882–1945) independently developed many of the same ideas, and possessing greater resources was actually able to build a working liquid-fuel rocket in 1926. Romanian-German Hermann Oberth (1894–1989) learned of the work of his colleagues just as he was about to publish his treatise, The Rocket into Planetary Space, in 1923. On the basis of the work of these pioneers, spaceflight societies were founded in Germany (1927), the United States (1930), Russia (1931), and Great Britain (1933). The German, U.S., and Russian groups independently duplicated Goddard’s working liquid-fuel rocket, although Goddard refused to cooperate with the others in the vain hope that he could develop unaided the technology to send an unmanned rocket to the moon. United only by publications and occasional visits, these groups formed an international social movement dedicated to space travel for transcendent motives that were neither economic nor political.

As the financial troubles of the Great Depression deepened, the space-travel movement struggled to survive. Especially in Germany, and later in the United States and Russia, the movement entered into a marriage of convenience with the military. The Treaty of Versailles ending World War I (1914–1918) had limited German artillery and aircraft but did not mention rockets. Members of the movement, notably Oberth’s young protégé Wernher von Braun (1912–1977), presented liquid-fuel rockets to the German army as effective weapons, although development of conventional solid-fuel rockets would have been a better choice for military purposes. Near the end of World War II (1939–1945), von Braun’s team completed development of the 300-mile-range V-2 rocket, demonstrating the potential of liquid-fuel technology for spaceflight. Starting with the launch of Sputnik I in 1957, the Soviet Union and the United States competed for international prestige through aggressive space programs, until the landing of the Apollo 11 lunar module on the moon in 1969.

On the basis of a huge library of technical and scholarly publications, the facts of the history of space exploration to date are clear, but the social-scientific interpretation is hotly debated. The view around 1960 was that international propaganda competition was the main driver, as has been summarized by Vernon van Dyke (1964). Amitai Etzioni (1965) argued that the American space program was a useless extravagance through which the military-industrial complex looted the national treasury. Then, John Logsdon (1970) argued that President John F. Kennedy’s (1917–1963) decision to go to the moon was a means for reviving the political spirit of his New Frontier program after defeats in 1961 with the aborted Bay of Pigs invasion of Cuba and in a meeting with the Soviet leader Nikita Khrushchev (1894–1971). William Bainbridge (1976) took the argument one step further, suggesting that in Germany and the Soviet Union, as well as in the United States, leaders of the transcendental spaceflight movement had cleverly manipulated beleaguered political leaders to invest in space as a symbolic solution to their inferiority in competition with other leaders. Michael Neufeld (1996) has argued against this thesis in the case of Germany, asserting that technically competent military engineers possessed a correct estimation of the military potential of the technology. Walter McDougall (1985) argued against this view in the case of the Soviet Union, stating that Marxist ideology naturally supported visionary technological projects. Most recently, Logsdon (2006) has argued that the American space program has been trapped in a vicious circle, as members of the movement convince political leaders to undertake technically demanding projects, but the public is not willing to invest enough to make them successful.

SOCIETAL IMPLICATIONS

Public opinion has long been generally favorable toward the space program but has never been a driving force in motivating development of the technology. In October 1947, a Gallup poll asked 1,500 Americans, “How long do you think it will be before man will be able to fly to the moon?” Only 21 percent guessed a particular year, 38 percent said “never,” and the remainder had nothing to say on the topic. Throughout the Apollo program, a majority tended to feel the project was not worth the cost. Americans’ enthusiasm for the actual moon landing faded fast after 1969, possibly accelerated by a general loss of confidence in science and technology that prevailed until the mid-1970s. Since then, majorities have tended to feel that the National Aeronautics and Space Administration (NASA) was doing a good job, but they give space exploration a low priority for funding. The responses of 1,400 Americans to the General Social Survey in 2004 were typical. Only 14.3 percent wanted funding increased, 43.4 percent wanted it kept at current levels, 36.8 percent wanted funding reduced, and the remaining 5.5 percent had no opinion.

Around 1970 there was considerable discussion of the potential terrestrial benefits of space, especially the second-order consequences from technology transfer, often called spin-offs. These were popularly conceptualized as distinct inventions made in the space program that found valuable uses in society. Many people count Tang powdered fruit drink, Teflon coatings on frying pans, and Velcro fasteners among these, but all existed before the space program. Real spin-offs actually are rare, but their stories fit popular misconceptions about how technological progress occurs, so they are legends that gain strength in the retelling. Far more important are the intended applications of space technology, the most prominent of which are communications satellites, navigation satellites (Global Positioning System), meteorology satellites, and military reconnaissance satellites. Difficult to measure, but probably of equal value, is the general stimulus to scientific and technological development achieved by the space program through increasing the technical expertise in the population, widely disseminating abstract technical ideas that may contribute to innovations far from their original sources, and inspiring young people to study science.

When Bainbridge (1991) asked two thousand students at Harvard University in 1986 to identify the possible goals for the space program, they came up with a list of 125 goals that could be clustered into groups that served different values. Some goals were technical and economic, including the benefits of satellites listed above, spin-offs, possible manufacturing in the vacuum and weightlessness of space, new knowledge for sciences like physics and astronomy, and preservation of the earth’s environment. A different set of goals stressed emotional and idealistic values, such as spiritual fulfillment, personal inspiration, artistic and aesthetic transcendence, satisfaction of curiosity, and the building of world harmony. A small group of items concerned national pride, defense, and military capabilities in space. Finally, a number of far-out but reasonably popular goals envisioned colonization of the solar system and the discovery of extraterrestrial life.

The early decades of the twenty-first century appear to be a transition period, in which predictions would be especially hazardous. China has launched men into orbit, thereby demonstrating the quality of its technology, especially to the propaganda disadvantage of Japan, which has pursued a half-hearted and largely unsuccessful space program. Both Russia and the European Union have well-established space launch capabilities but lack ambitious goals. After failing twice to develop a successor to the space shuttle in the National Aerospace Plane and the X-33, and running more than fifteen years overdue in completing the space station, the U.S. space program clearly required fundamental redirection. The initial phase of reorganization, announced in 2004, severely cut back scientific research and technological development in favor of very long-term plans for adventurous but poorly motivated human voyages to the Moon and Mars.

As any science fiction fan would be happy to explain to any social scientist willing to listen, the long-term social implications of space exploration could possibly be profound. Despite daunting technical and economic hurdles, the colonization of Mars and of several large satellites in the solar system could lead to a time when more humans lived off the Earth than on it. Some think we will transform ourselves radically to become better adapted to those alien environments and better prepared for interstellar travel. If so, space travel could bring about a new adaptive radiation event comparable to that which produced the human species five million years ago in East Africa, what the science fiction writer Alfred Bester (1913–1987) called “arrival of the fittest” in his novel, The Stars My Destination (1956). If the social scientist scoffed at such ideas, the science fiction fan might comment there must have been chimpanzees five million years ago who scoffed as well.

SEE ALSO Bay of Pigs; Industry; Mars; Science Fiction; World War II

BIBLIOGRAPHY

Bainbridge, William Sims. 1976. The Spaceflight Revolution: A Sociological Study. New York: Wiley.

Bainbridge, William Sims. 1991. Goals in Space: American Values and the Future of Technology. Albany: State University of New York Press.

Bauer, Raymond. 1969. Second-Order Consequences: A Methodological Essay on the Impact of Technology. Cambridge, MA: MIT Press.

Etzioni, Amitai. 1964. The Moon-Doggle: Domestic and International Implications of the Space Race. Garden City, NY: Doubleday.

Ginzberg, Eli, James W. Kuhn, Jerome Schnee, and Boris Yavitz, eds. 1976. Economic Impact of Large Public Programs: The NASA Experience. Salt Lake City, UT: Olympus.

Launius, Roger D. 2003. Public Opinion Polls and Perceptions of U.S. Human Spaceflight. Space Policy 19: 163–175.

Logsdon, John M. 1970. The Decision to Go to the Moon: Project Apollo and the National Interest. Cambridge, MA: MIT Press.

Logsdon, John M. 2006. “A Failure of National Leadership”: Why No Replacement for the Space Shuttle. In Critical Issues in the History of Spaceflight, ed. Steven J. Dick and Roger D. Launius, 269–300. Washington, DC: NASA.

McDougall, Walter A. 1985. The Heavens and the Earth: A Political History of the Space Age. New York: Basic Books.

Neufeld, Michael, 1996. The Rocket and the Reich: Peenemunde and the Coming of the Ballistic Missile Era. Cambridge, MA: Harvard University Press.

Ordway, Frederick I., III., Carsbie C. Adams, and Mitchell R. Sharpe. 1971. Dividends from Space. New York: Crowell.

Roy, Stephanie A., Elaine C. Gresham, and Carissa Bryce Christensen. 2000. The Complex Fabric of Public Opinion on Space. Acta Astronautica 47: 665–675.

Van Dyke, Vernon. 1964. Pride and Power: The Rationale of the Space Program. Urbana: University of Illinois Press.

William Sims Bainbridge

SPACE EXPLORATION

Triumph to Chaos

The National Aeronautics and Space Administration (NASA) witnessed both great triumph as well as immense downfall in the 1980s. With the formulation of the Space Transportation System (STS), more commonly referred to as the space shuttle, NASA fundamentally shifted its approach to space travel. The space shuttle was to supersede traditional expendable launch vehicles (ELVs), as it was to be the first in the line of reusable spaceships. Competition in the race for space had increased in recent years, as both Europe and the Soviet Union had found more-economical methods of exploration. With the shuttle in operation all appeared in order for NASA, an organization that had long been underfunded by the federal government and was searching for a new symbol to retain its prestige as the premier space exploration organization in the world. The 1986 space shuttle Challenger explosion derailed this progress, and the entire space program was placed in great jeopardy. The explosion and its subsequent scrutiny by the goverment, scientists, and the media left NASA reeling and searching for stability, respect, and direction. NASA was scolded for its emphasis on style and gimmickry over science and safety, and the organization was ill prepared to fend off such attacks. In 1988 NASA attempted to revive its tarnished image with a remodeled and internally redesigned Discovery shuttle. NASA also achieved a great level of success with its outer-space probes, such as Voyager 2, which had been launched in 1977 and surpassed all the expectations of its creators.

Space Shuttles

NASA launched the space shuttle Columbia on 12 April 1981. Columbia was to be the first in a long line of reusable, cost-efficient spacecraft. The shuttles were multifunctional vehicles designed to provide reliable and consistent travel into space. Their shape was similar to that of airplanes; yet shuttles could carry with them up to seven passengers, several satellites, and had a cargo bay fifteen feet wide and sixty feet long that could haul payloads up to sixty-five thousand pounds. They were launched with the aid of two solid booster rockets and an external tank, expendable pieces that separated from the shuttle once it had cleared the earth's atmosphere. NASA touted the craft as being able to perform dozens of missions a year with minimal repair. The shuttle was unable to perform under the vigorous standards that were set for it, however, and as a result NASA frequently cut corners and sacrificed safety to meet their goals.

Successes

Despite problems with the program, the shuttle accomplished a string of historic successes, one of which was the fifth shuttle flight on 11 November 1982, the first operational mission, which launched two communication satellites. Sally K. Ride made history on 18 June 1983, when she became the United States' first woman astronaut in space. Other memorable flights included those in which members of the United States Congress rode on board and flights in which commercial satellites were deployed, retrieved, and repaired in space. NASA intended to have a team of shuttles constantly deployed; yet its schedule was severely obstructed by technical, financial, and weather constraints. Other space efforts, such as President Reagan's Strategic Defense Initiative (SDI) and several military and commercial satellites, were either tabled or delayed due to the inconsistency of shuttle launch flights and cost overruns.

Disaster

On 28 January 1986 the United States witnessed a terrible disaster as the space shuttle Challenger exploded seventy-four seconds after liftoff. The seven crew members on board were killed as the shuttle became engulfed in flames. The astronauts, five males and two females, were pilot Michael J. Smith, flight commander Francis R. Scobee, physicist Ronald E. McNair, electrical engineer Judith A. Resnik, aeronautical engineer Ellison S. Onizuka, electrical engineer Gregory B. Jarvis, and high-school social studies teacher Sharon Christa McAuliffe. After twenty-four successful missions NASA and the country had come to see space shuttle launches as routine, but this event changed those perceptions forever.

A SCHOOLTEACHER'S DREAM

One of the seven crew members killed in the January 1986 Challenger explosion was not an astronaut at all but a thirty-seven-year-old school-teacher from Concord, New Hampshire, named S. Christa McAuliffe. Selected to become a member of the Challenger crew over eleven thousand other applicants, McAuliffe was to be the first private citizen in space and was to be one of NASA's greatest examples of public relations. Her role in the mission was to relate basic mission functions to the American public and to teach a class from space. Sadly, the shuttle accident shattered all this and shocked the nation that had followed her from her selection to the shuttle's liftoff. After McAuliffe's death, several tribute ceremonies were held for her and her fellow astronauts as the entire nation mourned their loss.

Sources:

Jerry Adler, "We Mourn Seven Heroes," Newsweek, 107 (10 February 1986): 26;

Stanley N. Wellborn and others, "We Will not Disappoint Them," U.S. News and World Report, 100 (10 February 1986): 14.

Inquiry

The causes of the Challenger explosion were studied by the Rogers Commission, which identified two primary reasons for the shuttle's destruction. The first lay in the faulty design of the craft's rubber O-rings, the seals used to join sections of the two solid-rocket boosters on either side of the shuttle. The rings' function was to keep certain gases from escaping by expanding to fill the gaps. They were sensitive to temperature shifts, and their designer, Morton Thiokol, and NASA were both familiar with the fact that the rings had sometimes failed to expand properly, but they had underestimated the importance of the problem. The second major flaw the commission named was the fact that the Challenger was launched at a much colder temperature than any other previous launch. Other discoveries of the commission shed a harsh light on NASA, suggesting that it was an organization riddled with incompetence and a top-heavy bureaucracy. The House Science and Technology Committee concurred with the Rogers Commission's finding, which blamed NASA for creating unachievable aims in such short periods of time. On 15 August 1986 President Reagan commissioned NASA to begin construction of a new shuttle and to place safety issues as a primary concern.

Voyager 2.

The success of the Voyager satellite program enabled the world to witness what could be accomplished when human ingenuity was put to the ultimate test. The Voyager 2 satellite continued to make history as it zoomed across the solar system surveying the Earth's neighboring planets. Launched on 20 August 1977, Voyager 2 was one of two probes created by NASA's Jet Propulsion Laboratory (JPL) to help give scientists and humanity a more accurate view of the solar system and what lay beyond it. Voyager 2 examined the planet Saturn on 25 August 1981 and the planet Uranus on 24 January 1986, recording spectacular findings from both locations. The satellite's future upon clearing the solar system appeared unsure. By 1989 Voyager 2 had outdone even the greatest of expectations as it reached the planet Neptune. The satellite's recording instruments captured data about this amazing cold planet and its many moons and broadcast them to scientists on Earth. Although its recording cameras were expected to break down subsequently, the satellite's other instruments, powered by radioactive plutonium thermal generators, were expected to function for quite some time to come. By the year 2025 all communications with Voyager 2 were expected to cease because of increased distance and declining power levels. With the hope that the satellite might be retrieved by other intelligent life in the galaxy, a recording of greetings and sounds of the Earth was placed on a twelve-inch copper disc and installed inside Voyager 2.

Space Stations

Many scientists in NASA viewed man's ultimate goal as living in space, and talk of the creation of the world's most sophisticated space station grew more spirited in the 1980s. Inspired by the Soviet Mir space station and earlier United States efforts such as Skylab, NASA pushed for the creation of a large modern space station to be constructed 250 miles above the Earth. NASA envisioned experiments in chemistry, biology, and physics to be performed on this space station, and it was touted as the perfect point from which to launch spacecraft to Mars and other planets. Lastly, the space station was to ensure United States dominance in the race for space into the next century. The ultimate station design was called Freedom and was to begin construction in 1995. It would be five hundred feet long, contain four modules for living and working, and be powered by solar panels. NASA faced severe criticism to its "orbiting dream house," much of which came from members of Congress who questioned the need for such a large-scale space program and balked at the possible $16 billion price tag. Other criticism came when blueprint plans and timelines for construction were announced. By 1989 the station's future was questionable.

Sources:

Jerry Adler, "We Mourn Seven Heroes," Newsweek, 107 (10 February 1986): 26;

Stuart F. Brown, "20 Years After Apollo: Is the U.S. Lost in Space?," Popular Science, 235 (July 1989): 63-75;

Steve Budiansky and Robert Kaylor, "What's Wrong with America's Space Program," U.S. News and World Report, 103 (28 December 1987 - 4 January 1988): 32-34;

Leon Jaroff, "The Last Picture Show," Time (4 September 1989);

Jerry Kluger, "NASA's Orbiting Dream House," Discover, 10 (May 1989): 68-72;

Larry Martz, "America Grounded," Newsweek, 110 (17 August 1987): 34-42;

Frank Trippett, "Milk Run to the Heavens," Time, 117 (12 January 1981): 10-14.

space exploration In 1903 the Russian physicist Konstantin Tsiolkovsky was developing ideas for space rockets fuelled by liquefied gas and by 1926 Robert Goddard in the USA had successfully designed the first liquid-fuelled rocket. There followed considerable German research into rockets, culminating in the launch of the V-2 rocket in 1944. In 1957 the Soviet Union surprised the USA by putting the first artificial satellite, Sputnik I, in orbit; this was followed by the US Explorer I in 1958. Yuri Gagarin was the first man in space in 1961, followed by John Glenn in 1962. In 1961 President KENNEDY proposed the APOLLO PROGRAMME to achieve a manned lunar landing by 1970, and in 1969 Neil Armstrong and Edwin (‘Buzz’) Aldrin landed on the Moon. The Soviet Union concentrated on unmanned flights, Luna IX achieving a soft landing on the Moon in 1966. In the early 1970s space stations were launched by both the USA and the Soviet Union, and in 1975 an Apollo capsule linked up with a Soviet Soyuz capsule. Unmanned flights have been made to Venus and Mars, while the US probe, Voyager 2, launched in 1977, reached Neptune in 1989. In 1981 the USA launched a space shuttle, the first reusable space craft, but its commercial and scientific programme was interrupted for two years by the explosion of the shuttle, Challenger, on lift-off in 1986. In 1986 the giant Soviet modular space station, Mir, was launched, with astronauts being ferried to the station by Soyuz spacecraft, followed in 1987 by the placing in space of the powerful Energiya station. The Hubble space telescope, which can produce images of other solar systems, was launched from a US shuttle in 1990. Its faulty mirror limited observations until it was repaired by astronauts in the space shuttle Endeavour in 1993. An international space station, Freedom, conceived by the USA in 1984, was due to become operational in the late 1990s. Space technology has resulted in numerous applications, and telecommunication satellites have greatly improved global communications; while meteorological satellites provide advance weather information, and reconnaissance satellites register the Earth's resources and military information.

space exploration Using spacecraft to investigate outer space and heavenly bodies. On October 4, 1957, the Soviet Union launched the first artificial satellite, Sputnik 1, into Earth orbit. Soviet cosmonauts, and their American equivalents, astronauts, orbited the Earth soon after. Unmanned space probes crash-landed on the Moon, sending back pictures to Earth during the descent. Then came soft landings, and probes orbiting the Moon showed its hidden side for the first time. By 1968, Soviet scientists developed techniques for returning a Moon orbiter safely to the Earth. In 1969, the US Apollo 11 mission became the first to place a man on the Moon. By that time, the Soviet Union had sent probes to explore Mars and Venus. CHRONOLOGY: First probe to land on the Moon: Lunik 2, launched September 12, 1959. First manned spaceflight: Yuri Gagarin, April 12, 1961. First close-up pictures of Mars: Mariner 4, received July 14, 1965. First person to walk on the Moon, Neil Armstrong, July 20, 1969. First pictures from surface of another planet: Venera 9, received from Venus on October 22, 1975. First probes to land on Mars, Viking 1 and 2, July 1976. Fly-bys of Voyager 2: Jupiter (1979), Saturn (1981), Uranus (1986), Neptune (1989). First space shuttle: Columbia, launched April 12, 1981. Giotto probe, launched 1985, flew within 600km (380mi) of Halley's Comet, sending back photographs and data. Galileo project, launched October 1989, photographed the asteroids Gaspra (1991) and Ida (1993), dropped a sub-probe (1995) into Jupiter's atmosphere and provided detailed data on Galilean satellites; Clementine probe (1994), discovered what are thought to be water-ice deposits in craters of the Moon; Solar and Heliospheric Observatory (SOHO) probe, launched 1995, provided data on the Sun's interior until 2000; Mars Pathfinder mission, launched December 1996, landed on Mars to deploy a ‘microrover’ (Sojourner) to explore and collect rock samples; Cassini space probe (launched 1997) on a seven-year journey towards Saturn.