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S (chemical element)
nonmetallic chemical element belonging to the oxygen group (Group 16 [VIa] of the periodic table), one of the most reactive of the elements. Pure sulfur is a tasteless, odourless, brittle solid that is pale yellow in colour, a poor c...
s (unit of measurement)
metric unit of volume equal to one cubic metre, or 1,000 litres. The stere (from Greek stereos, “solid”) was originally defined by law and used in France in 1793, primarily as a measure for firewood. It is thus the metric counterpart of the cord, one standard cord (128 cubi...
s (unit of time)
fundamental unit of time, now defined in terms of the radiation frequency at which atoms of the element cesium change from one state to another....
S (4th-century biblical manuscript)
the earliest known manuscript of the Christian Bible, compiled in the 4th century ad....
S (science)
Although evidence existed that the northern Atlantic Ocean was becoming significantly less salty, scientists did not know how great the change in salinity would have to be in order to trigger a major shift in climate. A number of scientists were skeptical that abrupt climate change was a near-term threat. David Battisti of the University of Washington noted that at the rate at which the......
S/2005 P1 (moon of Pluto)
Pluto’s other three moons, Hydra, Nix, and one provisionally called P4 on its discovery, are much smaller than Charon—81, 106, and 13–34 km (50, 66, and 8–21 miles) in diameter, respectively. (P4’s diameter is given as a range because its albedo is not precisely known.) They revolve around Pluto outside Charon’s path in nearly circular orbits (like Charon)...
S/2005 P2 (moon of Pluto)
Pluto’s other three moons, Hydra, Nix, and one provisionally called P4 on its discovery, are much smaller than Charon—81, 106, and 13–34 km (50, 66, and 8–21 miles) in diameter, respectively. (P4’s diameter is given as a range because its albedo is not precisely known.) They revolve around Pluto outside Charon’s path in nearly circular orbits (like Charon)...
S/A (navigation)
...two pseudo-random binary pulse trains: a 1-megabit-per-second civilian C/A-code (coarse acquisition code) and a 10-megabit-per-second military P-code (precision code). Until 2000, a feature known as selective availability (S/A) intentionally degraded the civilian signal’s accuracy; S/A was terminated in part because of safety concerns related to the increasing use of GPS by civilian mari...
S Andromeda (star)
...Milky Way Galaxy. If this was the case, it was argued, then its extraordinary brightness must indicate that M31 cannot be very far away, certainly not outside the local system of stars. Designated S Andromeda in conformity with the pattern of terminology applied to stars of variable brightness, this supposed nova was a strong argument in favour of the hypothesis that nebulae are nearby objects....
s ap (unit of weight)
unit of weight in the apothecaries’ system, equal to 20 grains, or one-third dram, and equivalent to 1.296 grams. It was sometimes mistakenly assigned to the avoirdupois system. In ancient times, when coinage weights customarily furnished the lower subdivisions of weight systems, the scruple (from...
S band (frequency band)
The ASR-9 system operates at frequencies from 2.7 to 2.9 GHz (within the S band). Its klystron transmitter has a peak power of 1.3 megawatts, a pulse width of 1 microsecond, and an antenna with a horizontal beamwidth of 1.4 degrees that rotates at 12.5 revolutions per minute (4.8-second rotation period)....
S Doradus (star)
variable supergiant star in the Large Magellanic Cloud (the latter is one of two galactic companions to the Milky Way Galaxy). S Doradus (and the Large Magellanic Cloud) is visible to viewers in the Southern Hemisphere in the constellation Dorado. It i...
S effect (psychology)
...pitched. If the unfilled limits are defined by successive stimuli from different places, duration appears longer when the distance between the two sources is greater; this is called the S effect or kappa effect. The reverse is the tau effect, in which the distance is perceived as being wider when the interval between successive stimuli is longer....
S stage (cytology)
...ordered sequence of events that occur in a cell in preparation for cell division. The cell cycle is a four-stage process in which the cell increases in size (gap 1, or G1, stage), copies its DNA (synthesis, or S, stage), prepares to divide (gap 2, or G2, stage), and divides (mitosis, or M, stage). The stages G1, S, and G2 make up interphase, which accounts for the span between cell divisions......
“S togo berega” (work by Herzen)
...and human will. He developed these themes in two brilliant but rather confused works, Pisma iz Frantsii i Italii (“Letters from France and Italy”) and S togo berega (From the Other Shore). His disillusionment was vastly increased by his wife’s infidelity with the radical German poet Georg Herwegh and by her death in 1852....
S wave (seismology)
Of the body waves, the primary, or P, wave has the higher speed of propagation and so reaches a seismic recording station faster than the secondary, or S, wave. P waves, also called compressional or longitudinal waves, give the transmitting medium—whether liquid, solid, or gas—a back-and-forth motion in the direction of the path of propagation, thus stretching......
S&H Green Stamps (trading stamps)
Trading stamps appeared in the United States and Great Britain in the late 19th century. The most popular trading stamp program in the United States, S&H Green Stamps, was sponsored by Sperry & Hutchinson. The company started operations in 1896 and flourished from the 1930s through the 1960s. In 1964 the S&H Green Stamp catalog became the largest single publication distributed...
S&P 500 (stock market)
in the United States, a stock market index that tracks 500 publicly traded domestic companies. It is considered by many investors to be the best overall measurement of American stock market performance....
S&S-Arrow (American company)
...the tide when he opened the doors to Disneyland in Anaheim in July 1955 and revitalized the notion of amusement parks. Disney commissioned the Arrow Development Company (later Arrow Dynamics; now S&S-Arrow), led by Ed Morgan and Karl Bacon, to design the bobsled-style Matterhorn (1959), the first steel coaster. Tubular steel rails and nylon wheels expanded the possibilities of coaster......
S-2 (missile)
The French deployed the first of their solid-fueled S-2 missiles in 1971. These two-stage IRBMs carried a 150-kiloton warhead and had a range of 1,800 miles. The S-3, deployed in 1980, could carry a one-megaton warhead to a range of 2,100 miles....
S-3 (missile)
The French deployed the first of their solid-fueled S-2 missiles in 1971. These two-stage IRBMs carried a 150-kiloton warhead and had a range of 1,800 miles. The S-3, deployed in 1980, could carry a one-megaton warhead to a range of 2,100 miles....
S-37 (Russian aircraft)
...Its Su-34 fighter-bomber began replacing the Su-24, while the redesigned Su-39 ground-attack aircraft began substituting for its older Su-25 variant. Its fifth-generation, multirole, all-weather S-37 Berkut air-superiority fighter, first flown in 1997, was equipped with state-of-the-art electronics, forward-swept wings, and thrust vector control. In competition with MiG for the international......
S-42 (seaplane)
...Its Su-34 fighter-bomber began replacing the Su-24, while the redesigned Su-39 ground-attack aircraft began substituting for its older Su-25 variant. Its fifth-generation, multirole, all-weather S-37 Berkut air-superiority fighter, first flown in 1997, was equipped with state-of-the-art electronics, forward-swept wings, and thrust vector control. In competition with MiG for the international......
S-A node (nerve bundle)
...is inherent in all cardiac muscle, but in myogenic hearts the pacemaker is derived from cardiac tissue. The pacemaker in mammals (and also in birds) is an oblong mass of specialized cells called the sinoatrial node, located in the right atrium near the junction with the venae cavae. A wave of excitation spreads from this node to the atrioventricular node, which is located in the right atrium......
S-adenosyl methionine (chemical compound)
...The first known optically active sulfur compounds were sulfonium salts, prepared in 1900. A number of sulfonium salts occur in nature; some examples include S-adenosyl methionine, a key biological source of the methyl group; thetin or 3-dimethylsulfonium propanoate,......
S-Bahn (railway, Berlin, Germany)
Modern rapid transit systems have existed since the 19th century. Construction of the Stadt- or Schnellbahn (S-Bahn), a largely elevated and partly underground railway system, began in 1871, and building of the subway, or Untergrundbahn (U-Bahn), was initiated in 1897. By World War II the city had one of the finest rapid transit systems in Europe. After the erection of the wall, the bus became......
s-block element (chemistry)
The metal in main-group organometallic compounds can be any of the elements in the s block (i.e., groups 1 and 2) or any of the heavier elements in groups 13 through 15. (Groups 13–18 constitute the p block.) The elements at the borderline between the d block and p block—namely, zinc, cadmium, and mercury—will be discussed along with the......
S-class asteroid
...a close flyby was Gaspra, which was observed in October 1991 by the Galileo spacecraft en route to Jupiter. Galileo’s images, taken from a distance of about 5,000 km, established that Gaspra, an S-class asteroid, is an irregular body with dimensions of 19 × 12 × 11 km. Nearly two years later, in August 1993, Galileo flew by (243) Ida, another S-class asteroid. Ida was found...
’s-Hertogenbosch (Netherlands)
gemeente (municipality), south-central Netherlands. It is situated where the Dommel and Aa rivers join to form the Dieze and lies along the Zuidwillemsvaart (canal)....
S-matrix (quantum mechanics)
in quantum mechanics, array of mathematical quantities that predicts the probabilities of all possible outcomes of a given experimental situation. For instance, two particles in collision may alter in speed and direction or even change into entirely new particles: the S-matrix for the collision gives the likelihood of each possibility. Complete knowledge of the S-matrix for all ...
s-orbital (physics)
As noted above, a subshell with quantum number l consists of 2l + 1 individual orbitals. Thus, an s subshell (l = 0) consists of a single orbital, which is called an s orbital; a p subshell (l = 1) consists of three orbitals, called p orbitals; and a d subshell (l = 2) consists of five orbitals, called d orbitals. The......
S-potential (physiology)
...manners, transmit their effects to bipolar and horizontal cells. The latter neurons have been studied from the point of view of their colour-coding. The potentials recorded from them were called S-potentials; these were of two types, which classified them as responding to colour (C-units) and luminosity (L-units)....
s-process (physics)
...elements, have been produced by successive capture of neutrons. Two processes of neutron capture may be distinguished: the r -process, rapid neutron capture; and the s -process, slow neutron capture. If neutrons are added to a stable nucleus, it is not long before the product nucleus becomes unstable and the neutron is converted into a proton. Outside a nucleus, a neutron......
S-R behaviour (psychology)
...to the event. In operant conditioning, the animal learns to associate a voluntary activity with specific consequences. In classical conditioning, the animal learns to associate a novel (conditioned) stimulus with a familiar (unconditioned) one. For example, in his study of classical conditioning, Russian physiologist Ivan Petrovich Pavlov demonstrated that by consistently exposing a dog to a......
S-R theory (psychology)
...of some essential features of a living organism. The neurological model is suggested from studies of the sensory receptor organs, internal neural structure, and effector organs of animals. Certain responses of an animal to stimuli are known by controlled observation, and, since the pioneering work of a Spanish histologist, Santiago Ramón y Cajal, in the latter part of the 19th and early....
s-state (physics)
As noted above, a subshell with quantum number l consists of 2l + 1 individual orbitals. Thus, an s subshell (l = 0) consists of a single orbital, which is called an s orbital; a p subshell (l = 1) consists of three orbitals, called p orbitals; and a d subshell (l = 2) consists of five orbitals, called d orbitals. The......
s-surface (geology)
The most obvious features of metamorphic rocks are certain planar features that are often termed s-surfaces. The simplest planar features may be primary bedding (akin to the layering in sedimentary rocks). As the rock crystallizes or recrystallizes under directed pressure, new crystals may grow in some preferred direction, sometimes subparallel to the primary bedding but often at new angles......
S-tank (Swedish tank)
The same 105-mm gun was adopted for the Pz. 61 and Pz. 68 tanks produced in Switzerland, the West German Leopard 1, the Swedish S-tank, the Japanese Type 74, and the Mark 1 and 2 versions of the Israeli Merkava. It was also retained in the original version of the U.S. M1 Abrams tank developed in the 1970s, but the subsequent M1A1 version of the 1980s was rearmed with a 120-mm gun originally......
S-twist (yarn and rope manufacturing)
...fibres or yarns together in a continuous strand, accomplished in spinning or playing operations. The direction of the twist may be to the right, described as Z twist, or to the left, described as S twist....
S-type granite (geology)
...protoliths (source rocks). These result in I-type granitoids, derived from igneous protoliths and containing moderate amounts of Al2O3 and high amounts of Na2O, and S-type granitoids, derived from sedimentary protoliths and containing high amounts of Al2O3 and relatively low amounts of Na2O. Amphibole and pyroxene are more common...
S-type granitoid (geology)
...protoliths (source rocks). These result in I-type granitoids, derived from igneous protoliths and containing moderate amounts of Al2O3 and high amounts of Na2O, and S-type granitoids, derived from sedimentary protoliths and containing high amounts of Al2O3 and relatively low amounts of Na2O. Amphibole and pyroxene are more common...
S-type star (astronomy)
Supplementary classes of cool stars include R and N (often called C-type, or carbon stars: less than 3,000 K), and S, which resemble class M stars but have spectral bands of zirconium oxide prominent instead of those of titanium oxide....
S-wave (seismology)
Of the body waves, the primary, or P, wave has the higher speed of propagation and so reaches a seismic recording station faster than the secondary, or S, wave. P waves, also called compressional or longitudinal waves, give the transmitting medium—whether liquid, solid, or gas—a back-and-forth motion in the direction of the path of propagation, thus stretching......
S. M. (American musician)
...sonic textures merged into a free-floating poetry of reference that epitomized 1990s college rock. The original members were lead singer, guitarist, and principal songwriter Stephen Malkmus (also known as S.M.; b. May 30 1966Santa Monica, Calif., U.S.) and guitarist......
S.6B (aircraft)
...it could demonstrate its potential. Nevertheless, it was the progenitor of a series of monoplanes that won the trophy three times, giving Britain permanent possession in 1931. The last of these, the S.6B, powered by a liquid-cooled Rolls-Royce racing engine with in-line cylinders, later raised the world speed record to more than 400 miles (640 km) per hour. The S.6B’s tapered fuselage an...
S.C. Johnson & Son (American company)
...publicity from 1936 to the present. Probably Wright’s most-admired work, it was later given to the state and was opened to visitors. The second important commission was the administrative centre for S.C. Johnson, wax manufacturers, at Racine, Wisconsin. Here Wright combined a closed, top-lit space with recurving forms and novel, tubular mushroom columns. The resulting airy enclosure is o...
S.D.B. (religious order)
The founder of the Salesians of Don Bosco (formally, the Society of St. Francis de Sales; S.D.B.) was St. John Bosco (Don Bosco), a young priest who focused his concern on the orphaned and homeless child labourers whom he encountered in Turin, Italy. In 1859, inspired by the example of St. Francis de Sales, Don Bosco founded the Salesians to befriend, educate, and help these impoverished boys.......
S.I. (political party, Indonesia)
the first nationalist political party in Indonesia to gain wide popular support. Founded in 1912 the party originated as an association of those Muslim merchants who wanted to advance their economic interests in relation to Chinese merchants in Java, but the association became political. It quickly gained mass support and st...
S.J. (religious order)
a Roman Catholic order of religious men, founded by St. Ignatius of Loyola, noted for its educational, missionary, and charitable works, once regarded by many as the principal agent of the Counter-Reformation and later a leading force in modernizing the church. The Jesuits have always been a controversial group regarded by some as a society to be feared and co...
S.M. (Roman Catholic congregation)
a religious congregation of the Roman Catholic church founded by William Joseph Chaminade at Bordeaux, Fr., in 1817. The Marianists, including the Brothers of Mary, developed from the sodality (a devotional association of the laity) of the Blessed Mother organized in 1800 by Chaminade. The Institute of the Daughters of Mary, or Marianist Sisters, was also a product of this sodality. The male congr...
S.O.Cist. (religious order)
member of a Roman Catholic monastic order that was founded in 1098 and named after the original establishment at Cîteaux (Latin: Cistercium), a locality in Burgundy, near Dijon. The order’s founding fathers, led by St. Robert of Molesme, were a group of Benedictine monks from the abbey of Molesme who were dissatisfied with the relaxed observance of their abbey and ...
S.S. Kresge Co. (American company)
major American retail chain with a history of marketing general merchandise primarily through discount and variety stores....
S.S. Tenacity (play by Vildrac)
...(1914–20) (1920; “Songs of a Desperate Man”) expresses anguish at the horrors of war. Vildrac’s best-known play, Le Paquebot Tenacity (produced, 1920; S.S. Tenacity), is a character study of two former soldiers about to immigrate to Canada. Michel Auclair (1921) revolves around the loyalty of a man to a woman who has rejected him. La......
S.V.D. (religious organization)
a Roman Catholic religious organization, composed of priests and brothers, founded in 1875 at Steyl, Neth., by Arnold Janssen to work in the foreign missions. Its members are engaged in all phases of missionary activity, from teaching in universities, colleges, and secondary schools to working among primitive peoples. In the...
S0 galaxy (astronomy)
These systems exhibit some of the properties of both the ellipticals and the spirals and seem to be a bridge between these two more common galaxy types. Hubble introduced the S0 class long after his original classification scheme had been universally adopted, largely because he noticed the dearth of highly flattened objects that otherwise had the properties of elliptical galaxies. Sandage’s...
S10 (satellite of Saturn)
Janus and Epimetheus are co-orbital moons—they share the same average orbit. Every few years they make a close approach, interacting gravitationally in such a way that one transmits angular momentum to the other, which forces the latter into a slightly higher orbit and the former into a slightly lower orbit. At the next close approach, the process repeats in the opposite direction. Tethys.....
S11 (satellite of Saturn)
Janus and Epimetheus are co-orbital moons—they share the same average orbit. Every few years they make a close approach, interacting gravitationally in such a way that one transmits angular momentum to the other, which forces the latter into a slightly higher orbit and the former into a slightly lower orbit. At the next close approach, the process repeats in the opposite direction. Tethys.....
S17 (satellite of Saturn)
...over the age of the solar system without driving the moons far beyond their current positions. The sharpness of the outer edge of the main ring system and the present orbits of such inner moons as Atlas are puzzling, and they appear to support the idea that the current ring system is much younger than Saturn itself....
S4 (logical system)
...but each could be consistently added to T as an extra axiom to produce a new and more extensive system. The system obtained by adding Lp ⊃ LLp to T is known as S4; that obtained by adding Mp ⊃ LMp to T is known as S5; and the addition of p ⊃ LMp to T gives the Brouwerian system...
S5 (logical system)
...system. The system obtained by adding Lp ⊃ LLp to T is known as S4; that obtained by adding Mp ⊃ LMp to T is known as S5; and the addition of p ⊃ LMp to T gives the Brouwerian system (named for the Dutch mathematician L.E.J. Brouwer), here called B for short....
SA (Nazi organization)
in the German Nazi Party, a paramilitary organization whose methods of violent intimidation played a key role in Adolf Hitler’s rise to power....
Ṣā Al-Ḥajar (ancient city, Egypt)
ancient Egyptian city (Sai) in the Nile River delta on the Canopic (Rosetta) Branch of the Nile River, in Al-Gharbīyah muḥāfaẓah (governorate). From prehistoric times Sais was the location of the chief shrine of Neith, the goddess of war and of the loom. The ...
Sá da Bandeira (Angola)
city, southwestern Angola, about 100 miles (160 km) east of Namibe (formerly Moçâmedes), to which it is linked by rail. The city was originally established in 1885 as a settlement for colonists from the Madeira Islands. It lies at an elevation of 5,774 feet (1,760 metres) in a valley of the Huíla Plateau and is surrounde...
Sa Dac (Vietnam)
town on the Mekong River delta, southern Vietnam. It is a river port, agricultural trading centre, and transshipment point for small craft on the left bank of the shallow Bassac River (Song Han Giang), 88 miles (140 km) southwest of Ho Chi Minh City...
Sá de Miranda, Francisco de (Portuguese author)
Portuguese poet who introduced Renaissance poetic forms to Portugal....
Sa Dec (Vietnam)
town on the Mekong River delta, southern Vietnam. It is a river port, agricultural trading centre, and transshipment point for small craft on the left bank of the shallow Bassac River (Song Han Giang), 88 miles (140 km) southwest of Ho Chi Minh City...
Sa El-Hagar (ancient city, Egypt)
ancient Egyptian city (Sai) in the Nile River delta on the Canopic (Rosetta) Branch of the Nile River, in Al-Gharbīyah muḥāfaẓah (governorate). From prehistoric times Sais was the location of the chief shrine of Neith, the goddess of war and of the loom. The ...
Sa galaxy (astronomy)
These normal spirals have narrow, tightly wound arms, which usually are visible because of the presence of interstellar dust and, in many cases, bright stars. Most of them have a large amorphous bulge in the centre, but there are some that violate this criterion, having a small nucleus around which is arranged an amorphous disk with superimposed faint arms. NGC 1302 is an example of the normal......
Sá, Mem de (captain-general of Brazil)
...in 1549 dispatched Tomé de Sousa as captain general, along with a small band of Jesuits headed by Manuel da Nóbrega. Through their efforts and those of the succeeding captain general, Mem de Sá (1557–72), workable policies for the colony were formed and implemented, and vigorous attempts were made to gather the Indians into settlements. There were eight captaincies b...
Sa Suisse Pour La Navigation Aérienne (Swiss airline)
Swiss airline formed in 2002 following the bankruptcy of Swiss Air Transport Company Ltd. (Swissair). The airline serves cities in Europe, Asia, Africa, the Middle East, and North and Latin America....
SA-1 Guild (missile)
The Soviet Union committed more technical and fiscal resources to the development of guided-missile air-defense systems than any other nation. Beginning with the SA-1 Guild, developed in the immediate postwar period, the Soviets steadily fielded SAMs of growing sophistication. These fell into two categories: systems such as the Guild, the SA-3 Goa, the SA-5 Gammon, and the SA-10 Grumble, which......
SA-10 Grumble (missile)
A new generation of Soviet SAM systems entered service in the 1980s. These included the SA-10 Grumble, a Mach-6 mobile system with a 60-mile range deployed in both strategic and tactical versions; the SA-11 Gadfly, a Mach-3 semiactive radar homing system with a range of 17 miles; the SA-12 Gladiator, a track-mobile replacement of Ganef; the SA-13 Gopher, a replacement for Gaskin; and the SA-14,......
SA-11 Gadfly (missile)
...new generation of Soviet SAM systems entered service in the 1980s. These included the SA-10 Grumble, a Mach-6 mobile system with a 60-mile range deployed in both strategic and tactical versions; the SA-11 Gadfly, a Mach-3 semiactive radar homing system with a range of 17 miles; the SA-12 Gladiator, a track-mobile replacement of Ganef; the SA-13 Gopher, a replacement for Gaskin; and the SA-14, a...
SA-12 Gladiator (missile)
...SA-10 Grumble, a Mach-6 mobile system with a 60-mile range deployed in both strategic and tactical versions; the SA-11 Gadfly, a Mach-3 semiactive radar homing system with a range of 17 miles; the SA-12 Gladiator, a track-mobile replacement of Ganef; the SA-13 Gopher, a replacement for Gaskin; and the SA-14, a shoulder-fired Grail replacement. Both Grumble and Gadfly had naval equivalents, the....
SA-13 Gopher (missile)
...deployed in both strategic and tactical versions; the SA-11 Gadfly, a Mach-3 semiactive radar homing system with a range of 17 miles; the SA-12 Gladiator, a track-mobile replacement of Ganef; the SA-13 Gopher, a replacement for Gaskin; and the SA-14, a shoulder-fired Grail replacement. Both Grumble and Gadfly had naval equivalents, the SA-N-6 and SA-N-7. The Gladiator might have been designed.....
SA-14 (missile)
...the SA-11 Gadfly, a Mach-3 semiactive radar homing system with a range of 17 miles; the SA-12 Gladiator, a track-mobile replacement of Ganef; the SA-13 Gopher, a replacement for Gaskin; and the SA-14, a shoulder-fired Grail replacement. Both Grumble and Gadfly had naval equivalents, the SA-N-6 and SA-N-7. The Gladiator might have been designed with an antimissile capability, making it an......
SA-2 Guideline (missile)
...and the SA-10 Grumble, which were deployed in defense of fixed installations; and mobile tactical systems capable of accompanying land forces. Most of the tactical systems had naval versions. The SA-2 Guideline, introduced in 1958, was the most widely deployed of the early SAMs and was the first surface-to-air guided-missile system used in combat. This two-stage missile with a solid booster......
SA-3 Goa (missile)
The SA-3 Goa, derived from the Guideline but modified for use against low-altitude targets, was first deployed in 1963—primarily in defense of fixed installations. The SA-N-1 was a similar naval missile....
SA-4 Ganef (missile)
The SA-4 Ganef was a long-range mobile system first deployed in the mid-1960s; the missiles, carried in pairs on a tracked launcher, used drop-off solid-fuel boosters and a ramjet sustainer motor. Employing a combination of radar command guidance and active radar homing, and supported by an array of mobile radars for target acquisition, tracking, and guidance, they could engage targets over the......
SA-5 Gammon (missile)
The SA-5 Gammon was a high- and medium-altitude strategic missile system with a range of 185 miles; it was exported to Syria and Libya. The SA-6 Gainful was a mobile tactical system with a range of two to 35 miles and a ceiling of 50,000 feet. Three 19-foot missiles were carried in canisters atop a tracked transporter-erector-launcher, or TEL, and the radar and fire-control systems were mounted......
SA-6 Gainful (missile)
...in the projectile that was sensitive to the reflected energy then homed onto the target. Like active guidance, semiactive guidance was commonly used for terminal homing. In the U.S. Hawk and Soviet SA-6 Gainful antiaircraft systems, for example, the missile homed in on radar emissions transmitted from the launch site and reflected off the target, measuring the Doppler shift in the reflected......
SA-7 Grail (missile)
...advances in seeker-head technology. Small, heat-seeking, shoulder-fired antiaircraft missiles first became a major factor in land warfare during the final stages of the Vietnam War, with the Soviet SA-7 Grail playing a major role in neutralizing the South Vietnamese Air Force in the final communist offensive in 1975. Ten years later the U.S. Stinger and British Blowpipe proved effective against...
SA-8 Gecko (missile)
The SA-8 Gecko, first deployed in the mid-1970s, was a fully mobile system mounted on a novel six-wheeled amphibious vehicle. Each vehicle carried four canister-launched, semiactive radar homing missiles, with a range of about 7.5 miles, plus guidance and tracking equipment in a rotating turret. It had excellent performance but, in Syrian hands during the 1982 conflict in Lebanon, proved......
SA-9 Gaskin (missile)
The SA-7 Grail shoulder-fired, infrared-homing missile was first deployed outside the Soviet Union in the final stages of the Vietnam War; it also saw extensive action in the Middle East. The SA-9 Gaskin carried four infrared-homing missiles on a turreted mount atop a four-wheeled vehicle. Its missiles were larger than the SA-7 and had more sophisticated seeker and guidance systems....
Sá-Carneiro, Mário de (Portuguese author)
poet and novelist, one of the most original and complex figures of the Portuguese Modernist movement....
Sa-ga zla-ba (Tibetan festival)
...the Buddha over his six religious opponents through debates and the performance of miracles. During this festival, special prayers are offered daily. Prayers, fasting, and charitable donations mark Sa-ga zla-ba (or Saga dawa), the celebration of the anniversary of Buddha’s birth, enlightenment, and death—three events that all occurred on the 15th day of the fourth month of the Tib...
Sa-in (Japanese government)
...subdivided into an executive branch, a legislative branch, and six other departments. Reorganized several times, the Dajōkan was finally restructured on Sept. 13, 1871, into three chambers: a Left Chamber (Sa-in), the legislative body; a Right Chamber (U-in), which directed the various ministries; and a Central Chamber (Sei-in), which subsumed the powers of the other two chambers....
SA-N-1 (missile)
The SA-3 Goa, derived from the Guideline but modified for use against low-altitude targets, was first deployed in 1963—primarily in defense of fixed installations. The SA-N-1 was a similar naval missile....
SA-N-3 Goblet (missile)
...systems were mounted on a similar vehicle, each of which supported four TELs. The missiles used semiactive radar homing and were powered by a combination of solid-rocket and ramjet propulsion. (The SA-N-3 Goblet was a similar naval system.) Gainful, the first truly mobile land-based SAM system, was first used in combat during the 1973 Arab-Israeli War and was highly effective at first against.....
Sa-skya (monastery, Tibet, China)
Tibetan Buddhist sect that takes its name from the great Sa-skya (Sakya) monastery founded in 1073, 50 miles (80 km) north of Mount Everest. The sect follows the teachings of the noted traveler and scholar ’Brog-mi (992–1072). He translated into Tibetan the important Tantric work Hevajra Tantra, which remains one of the basic texts of the order. He also......
Sa-skya-pa (Tibetan Buddhist sect)
Tibetan Buddhist sect that takes its name from the great Sa-skya (Sakya) monastery founded in 1073, 50 miles (80 km) north of Mount Everest. The sect follows the teachings of the noted traveler and scholar ’Brog-mi (992–1072). He translated into Tibetan the important Tantric work ...
Saa (people)
an indigenous people of southern Africa, related to the Khoekhoe (Khoikhoi). They live chiefly in Botswana, Namibia, and southeastern Angola. Bushmen is an Anglicization of boesman, the Dutch and Afrikaner name for them; saan (plural) or saa (singu...
Saab AB (Swedish firm)
Swedish high-technology company involved in defense, aviation, and aerospace. Its products include airplanes, missiles, electronics, and computers. Saab’s headquarters are in Linköping, Sweden....
Saab Aktiebolaget (Swedish firm)
Swedish high-technology company involved in defense, aviation, and aerospace. Its products include airplanes, missiles, electronics, and computers. Saab’s headquarters are in Linköping, Sweden....
Saab, Andrée (Egyptian-born French writer)
March 20, 1920Cairo, EgyptFeb. 6, 2011Paris, FranceEgyptian-born French writer who crafted both poetry and prose in which she explored themes germane to her native Middle East and to France, where she lived from 1946....
Saab Automobile AB (Swedish firm)
Swedish high-technology company involved in defense, aviation, and aerospace. Its products include airplanes, missiles, electronics, and computers. Saab’s headquarters are in Linköping, Sweden....
Saab-Scania AB (Swedish firm)
Swedish high-technology company involved in defense, aviation, and aerospace. Its products include airplanes, missiles, electronics, and computers. Saab’s headquarters are in Linköping, Sweden....
Saad al-ʿĀlī, Al- (dam, Egypt)
rockfill dam across the Nile River, at Aswān, Egypt, completed in 1970 (and formally inaugurated in January 1971) at a cost of about $1 billion. The dam, 364 feet (111 metres) high, with a crest length of 12,562 feet (3,830 metres) and a volume of 57,940,000 cubic yards (44,300,000 cubic metres), impounds a reservoir,...
Saada (Yemen)
town, northwestern Yemen, in the mountainous Yemen Highlands. It was the original capital of the Zaydī dynasty of imams (religious-political leaders) of Yemen (ad 860–1962). The effective founder of Ṣaʿdah as a base of Zaydī power was Imam Yaḥyā al-Hādī ilā al-Ḥāq...
Saʿādah, Anṭūn (Syrian politician)
Syrian political agitator who sought to unify Syria with neighbouring areas that he considered really parts of Syria....