Spaak \'spak\, Paul-Henri (b. Jan. 25, 1899, Schaerbeek, near Brus¬ sels, Belg.—d. July 31, 1972, Brussels) Belgian statesman. After practic¬ ing law (1921-31), he became a socialist member of the Chamber of Deputies in 1932. For most of the period from 1936 to 1966 he served as Belgium’s foreign minister, and he twice served as its premier (1938-39, 1947-50). An advocate of European cooperation, he helped form the Benelux Economic Union (1944) and helped draft the UN charter, and in 1946 he served as the UN General Assembly’s first president. He signed the Brussels Treaty, helped form NATO, and served as NATO’s secretary- general (1957-61). He also helped create the European Economic Commu¬ nity and the European Atomic Energy Community.
Spaatz YspatsV Carl (Andrews) known as Tooey Spaatz (b. June 28, 1891, Boyertown, Pa., U.S.—d. July 14,1974, Washington, D.C.) U.S. air-force officer. He flew as a combat pilot during World War I. During World War II he commanded the U.S. Strategic Air Forces in Europe (1944), directing the strategic bombing of Germany. In 1945, though per¬ sonally opposed to using atomic bombs against cities, he directed the atomic bombing of Japan under orders of Pres. Harry Truman. In 1947 he became the first chief of staff of the independent Air Force.
space contraction See Lorentz-FitzGerald contraction
space exploration Investigation of the universe beyond Earth’s atmosphere by means of manned and unmanned spacecraft. Study of the use of rockets for spaceflight began early in the 20th century. Germany’s research on rocket propulsion in the 1930s led to development of the V-2 missile. After World War II, the U.S. and the Soviet Union, with the aid of relocated German scientists, competed in the “space race,” making sub¬ stantial progress in high-altitude rocket technology (see staged rocket). Both launched their first satellites (see Sputnik; Explorer) in the late 1950s (followed by other satellites and unmanned lunar probes) and their first manned space vehicles (see Vostok; Mercury) in 1961. A succession of longer and more complex manned space missions followed, most nota¬
bly the U.S. Apollo program, including the first manned lunar landing in 1969, and the Soviet Soyuz and Salyut missions. Beginning in the 1960s, U.S. and Soviet scientists also launched unmanned deep-space probes for studies of the planets and other solar system objects (see Pioneer; Venera; Viking; Voyager; Galileo), and Earth-orbiting astronomical observatories (see, for example, Hubble Space Telescope), which permitted observation of cosmic objects from above the filtering and distorting effects of Earth’s atmosphere. In the 1970s and ’80s the Soviet Union concentrated on the development of space stations for scientific research and military recon¬ naissance (see Salyut; Mir). After the dissolution of the Soviet Union in 1991, Russia continued its space program, but on a reduced basis owing to economic constraints. In 1973 the U.S. launched its own space station (see Skylab), and since the mid 1970s it has devoted much of its manned space efforts to the space shuttle program and, more recently, to develop¬ ing the International Space Station in collaboration with Russia and other countries.
space frame Three-dimensional truss based on the rigidity of the tri¬ angle and composed of linear elements subject only to compression or tension. Its simplest spatial unit is a tetrahedron having four joints and six members. A space frame forms a very strong, thick, flexible structural fabric that can be used horizontally or bent to a variety of shapes. The beauty of its open latticework web of lightweight tubular diagonals is only surpassed by its structural purity. R. Buckminster Fuller used this technol¬ ogy for some of his Dymaxion projects; in his Union Tank Car warehouse. Baton Rouge, La. (1958), a space frame reinforces an enormous geode¬ sic dome.
space shuttle formally Space Transportation System (STS)
Partially reusable rocket-launched vehicle developed by NASA to go into Earth orbit, transport people and cargo between Earth and orbiting space¬ craft, and glide to a runway landing on Earth. The first flight of a space shuttle into orbit took place in 1981. The shuttle consists of a winged orbiter that carries crew and cargo; an expendable external tank of liquid fuel and oxidizer for the orbiter’s three main rocket engines; and two large, reusable solid-propellant booster rockets. The orbiter lifts off ver¬ tically like an expendable launch vehicle but makes an unpowered descent similar to a glider. Each orbiter was designed to be reused up to 100 times. For manipulating cargo and other materials outside the orbiter, astronauts use a remotely controlled robot arm or exit the orbiter wearing space- suits. On some missions, the shuttle carries a European-built pressurized research facility called Spacelab in its cargo bay. Between 1981 and 1985, four shuttle orbiters were put into service: Columbia (the first in orbit), Challenger , Discovery , and Atlantis. Challenger exploded in 1986 during launch, killing all seven astronauts aboard; it was replaced in 1992 by Endeavour. From 1995 to 1998, NASA conducted shuttle missions to the Russian space station Mir to prepare for the construction of the Interna¬ tional Space Station (ISS). Beginning in 1998, the shuttle was used exten¬ sively to ferry components, supplies, and crews to the ISS. In 2003 Columbia disintegrated while returning from a space mission, claiming the lives of its seven-person crew.
space station Manned artificial structure designed to revolve in a fixed orbit as a long-term base for astronomical observations, study of Earth’s resources and environment, military reconnaissance, and investigations of materials and biological systems in weightless conditions. As of 2001, nine space stations have been placed in a low Earth orbit and occupied for varying lengths of time. The Soviet Union orbited the world’s first space station, Salyut 1, designed for scientific studies, in 1971. From 1974 to 1982 five more Salyut stations—two outfitted for military reconnaissance—were successfully placed in orbit and occupied. In 1986 the U.S.S.R. launched the core module of Mir, a scientific station that was expanded with five additional modules over the next decade. The U.S. orbited its first space station in 1973; called Skylab, it was equipped as a solar observatory and medical laboratory. In 1998 the U.S. and Russia began the in-orbit construction of the International Space Station (ISS), a complex of laboratory and habitat modules that would ultimately involve contributions from at least 16 countries. In 2000 the ISS received its first resident crew. See illustration on following page.
space-time Single entity that relates space and time in a four¬ dimensional structure, postulated by Albert Einstein in his theories of rela¬ tivity. In the Newtonian universe it was supposed that there was no connection between space and time. Space was thought to be a flat, three- dimensional arrangement of all possible point locations, which could be expressed by Cartesian coordinates; time was viewed as an independent
Wole Soyinka.
VERNON L SMITH
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1794 I spacecraft ► Spain
Soviet/Russian space station Mir, after completion in 1996. The date shown for each module is its year of launch. Docked to the station are a Soyuz TM manned spacecraft and an unmanned Progress resupply ferry.
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one-dimensional concept. Einstein showed that a complete description of relative motion requires equations that include time as well as the three spatial dimensions. He also showed that space-time is curved, which allowed him to account for gravitation in his general theory of relativity.