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  • 1968, Generation of (Spanish literature)
    The Generation of 1968 was recognized in the 1980s as a distinct novelistic group. It includes Esther Tusquets, Álvaro Pombo, and Javier Tomeo, together with nearly a dozen others who belong to this group chronologically if not by reason of aesthetic or thematic similarities. Tusquets is best known for a trilogy of thematically related but independent novels: El mismo mar de todos......
  • 1969 Academy Awards (awarded 1970)
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  • 1970 Academy Awards (awarded 1971)
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  • 1970, Compromise of (Yemeni history)
    ...al-Raḥmān al-Iryānī. Two years later, with the blessing of the two major foreign participants—Egypt and Saudi Arabia—the leaders of North Yemen agreed upon the Compromise of 1970, which established a republican government in which some major positions were assigned to members of the royalist faction. It was agreed that the imam and his family were not t...
  • 1971 Academy Awards (awarded 1972)
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  • 1972 Academy Awards (awarded 1973)
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  • 1973 Academy Awards (awarded 1974)
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  • 1974 Academy Awards (awarded 1975)
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  • 1975 Academy Awards (awarded 1976)
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  • 1976 Academy Awards (awarded 1977)
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  • 1977 Academy Awards (awarded 1978)
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  • 1977, Protocol of (international law)
    ...Geneva Conventions would apply (protecting only those not taking an active part in the hostilities). Further protection is given (mainly to those who do not take part in the conflict) by the second Protocol of 1977, which applies to civil wars in which dissident armed forces, under responsible command, exercise such control over a part of the territory of a contracting state as to enable them.....
  • 1978 Academy Awards (awarded 1979)
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  • 1978, Constitution of (Spanish history)
    ...negotiations among the leading political groups, the Spanish constitution was nearly unanimously approved by both houses of the legislature (it passed 551–11 with 22 abstentions) in October 1978. In a December referendum, the draft constitution was then approved by nearly 90 percent of voters. The constitution declares that Spain is a constitutional monarchy and advocates the essential.....
  • 1979 Academy Awards (awarded 1980)
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  • 1980 Academy Awards (awarded 1981)
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  • 1981 Academy Awards (awarded 1982)
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  • 1982 Academy Awards (awarded 1983)
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  • 1983 Academy Awards (awarded 1984)
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  • 1983 Beirut barracks bombings
    terrorist bombing attacks against U.S. and French armed forces in Beirut on Oct. 23, 1983 that claimed 299 lives. The attacks, which took place amid the sectarian conflict of the extremely damaging Lebanese civil war (1975–90), hastened the removal of the international peacekeeping force from Lebanon in February 1984....
  • 1983TB (asteroid)
    ...formation of planetary systems similar to that of the Sun. Other important findings included various clouds of interstellar gas and dust where new stars are being formed and an object, designated 1983TB, thought to be the parent body for the swarm of meteoroids known as Geminids....
  • 1984 (album by Van Halen)
    ...of Kiss led to their band’s critically acclaimed debut album, Van Halen (1978), which sold more than six million copies. Featuring the hits “Jump” and “Panama,” 1984 (1984) made megastars of the Los Angeles-based band. Soon after, flamboyant lead singer Roth left Van Halen to pursue a solo career. With his replacement, Hagar, the band produced th...
  • 1984 Academy Awards (awarded 1985)
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  • 1985 Academy Awards (awarded 1986)
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  • 1985, concordat of (Catholic and Italian history)
    With the signing of the concordat of 1985, Roman Catholicism was no longer the state religion of Italy. This change in status brought about a number of alterations in Italian society. Perhaps the most significant of these was the end to compulsory religious education in public schools. The new concordat also affected such diverse areas as tax exemptions for religious institutions and ownership......
  • 1986 Academy Awards (awarded 1987)
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  • 1986U7 (satellite of Uranus)
    ...They are estimated to be between about 10 and 80 km (6 and 50 miles) in radius, and they orbit the planet at distances between 49,800 and 86,000 km (31,000 and 53,500 miles). The innermost moon, Cordelia, orbits just inside the outermost rings, Lambda and Epsilon. An 11th tiny inner moon photographed by Voyager near the orbit of Belinda remained unnoticed in the images until 1999 and was not......
  • 1986U8 (satellite of Uranus)
    Voyager 2 found that the innermost two moons, Cordelia and Ophelia, orbit on either side of the Epsilon ring at exactly the right radii required for shepherding. Shepherds for the other rings were not observed, perhaps because the moons are too small to be seen in the Voyager images. Small moons may also be reservoirs that supply the dust leaving the ring system....
  • 1987 Academy Awards (awarded 1988)
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  • 1988 Academy Awards (awarded 1989)
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  • 1989 Academy Awards (awarded 1990)
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  • 1989N1R (astronomy)
    Images from Voyager 2, however, revealed a system of six rings, each of which in fact fully surrounds Neptune. The putative arcs turned out to be bright regions in the outermost ring, named Adams, where the density of ring particles is particularly high. Although rings also encircle each of the other three giant planets, none displays the striking clumpiness of Adams. The arcs are found within......
  • 1989N2R (astronomy)
    The other five known rings of Neptune—Galle, Le Verrier, Lassell, Arago, and Galatea, in order of increasing distance from the planet—lack the nonuniformity in density exhibited by Adams. Le Verrier, which is about 110 km (70 miles) in radial width, closely resembles the nonarc regions of Adams. Similar to the relationship between the moon Galatea and the ring Adams, the moon......
  • 1989N3R (astronomy)
    The other five known rings of Neptune—Galle, Le Verrier, Lassell, Arago, and Galatea, in order of increasing distance from the planet—lack the nonuniformity in density exhibited by Adams. Le Verrier, which is about 110 km (70 miles) in radial width, closely resembles the nonarc regions of Adams. Similar to the relationship......
  • 1989N4R (astronomy)
    Galle, the innermost ring, is much broader and fainter than either Adams or Le Verrier, possibly owing to the absence of a nearby moon that could provide a strong shepherding effect. Lassell consists of a faint plateau of ring material that extends outward from Le Verrier about halfway to Adams. Arago is the name used to distinguish a narrow, relatively bright region at the outer edge of......
  • 1990 Academy Awards (awarded 1991)
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  • 1991 Academy Awards (awarded 1992)
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  • 1992 Academy Awards (awarded 1993)
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  • 1992 QB1 (astronomy)
    The first Kuiper belt object (KBO) was discovered in 1992 by the American astronomer David Jewitt and graduate student Jane Luu. Designated 1992 QB1, the body is about 200–250 km (125–155 miles) in diameter, as estimated from its brightness. It moves in a nearly circular orbit in the plane of the planetary system at a distance from the Sun of about 44 astronomical units (AU; 1 AU is....
  • 1993 Academy Awards (awarded 1994)
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  • 1994 Academy Awards (awarded 1995)
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  • 1995 Academy Awards (awarded 1996)
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  • 1996 Academy Awards (awarded 1997)
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  • 1997 Academy Awards (awarded 1998)
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  • 1999 Chi Chi earthquake
    earthquake that began at 1:47 am local time on Sept. 21, 1999, below an epicentre 93 miles (150 km) south of Taipei, Taiwan. The death toll was 2,400 and some 10,000 people were injured. Thousands of houses collapsed, making more than 100,000 people homeless. The magnitude of the main shock was 7.7, resulting in about 10,000 bu...
  • 19th Dynasty (ancient Egyptian history)
    third king of the 19th dynasty of Egypt, whose reign (1279–13 bc) was the second longest in Egyptian history. In addition to his wars with the Hittites and Libyans, he is known for his extensive building programs and for the many colossal statues of him found all over Egypt....
  • 19th of April Movement (Colombian history)
    Unhappiness with the 1970 election gave rise in 1973–74 to another guerrilla group, the 19th of April Movement (Movimiento 19 de Abril, or M-19), named for the date that the group asserted the election was “stolen” from Pinilla. The M-19 launched itself to national attention when its members stole a sword that had belonged to Simón Bolívar. The group tended to......
  • 1D state (physics)
    ...the photodissociation of H2O into H2 + O (in the 1D state) and, in an accessorial manner, of CO2 into CO + O (in the 1D state). The 1D state is an excited state of the oxygen atom that decays spontaneously into the ground (lowest energy) state by emitting the forbidden red doublet, provided that it had not been quenched earlier b...
  • 1st Annual Academy Awards (awarded May 16, 1929)
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  • 1st South Carolina Volunteers (American military)
    ...and he supported John Brown both in Kansas (1856) and in his raid on Harpers Ferry, Virginia (1859). During the Civil War Higginson accepted command of the 1st South Carolina Volunteers, later the 33rd U.S. Colored Troops, the first black regiment in the U.S. armed forces. After 1864 he wrote a series of popular biographies and histories and a novel. Higginson discovered and encouraged the......
  • 1st Volunteer Cavalry (United States cavalry)
    in the Spanish–American War, one of a regiment of U.S. cavalry volunteers recruited by Theodore Roosevelt and composed of cowboys, miners, law-enforcement officials, and college athletes, among others. Their colourful and often unorthodox exploits received extensive publicity in the U.S. press. Col. Leonard Wood resigned as White House physician to comm...
  • 2 (number)
    The number 2 symbolizes many of the basic dualities: me/you, male/female, yes/no, alive/dead, left/right, yin/yang, and so on. Dualities are common in human approaches to the world, probably because of our preference for two-valued logic—yet another duality, true/false. Although 2 was female to the Pythagoreans, other numerological schemes viewed it as male. In Agrippa von Nettesheim...
  • 2 Chronicles (Old Testament)
    two Old Testament books that were originally part of a larger work that included the books of Ezra and Nehemiah. These three (Ezra and Nehemiah were one book in the Jewish canon) were the final books of the Hebrew Bible. Together they survey Israel’s history from Adam to the activity of Ezra and Nehemiah in the period after the Babylonian Exile (6th century bc). The uniformity...
  • 2-5 system (telephone system)
    ...BROoklyn 1234. With the growth of the telephone network, this three-letter and four-number local numbering system, which had only 512 possible central-office codes, was replaced in 1947 by the 2-5 system, which employed two letters and five numbers—e.g., WOodland 8-1234. The 2-5 system permitted the use of 640 office codes. Eventually, in order to comply with international......
  • 2-amino-4,6-pteridinedione (chemical compound)
    ...pteron, “wing”) has become apparent since the first known members of the group were discovered as pigments of butterfly wings. One example is the yellow pigment 2-amino-4,6-pteridinedione (xanthopterin)....
  • 2-bromo-2-chloro-1,1,1-trifluoroethane (drug)
    nonflammable, volatile, liquid drug introduced into medicine in the 1950s and used as a general anesthetic. Halothane rapidly achieved acceptance and became the most frequently used of the potent anesthetics, despite its substantially higher cost than ether and chloroform and its tendency to depress respiration and circulation. Its vapours are not nauseating or irritating to mucous membranes....
  • 2-butanol (chemical compound)
    any of four organic compounds having the same molecular formula but different structures: normal (n-) butyl alcohol, secondary (sec-) butyl alcohol, isobutyl alcohol, and tertiary (t-) butyl alcohol....
  • 2-butanone (chemical compound)
    The mass spectrum of the ketone 2-butanone serves as an example. The strongest peak in the spectrum is known as the base peak, and its intensity is arbitrarily set at a value of 100. The peak at m/z= 72 is the molecular ion and as such gives the molecular mass of the molecule. In high-resolution mass spectrometry, the mass of the molecular ion can be measured to an accuracy of 4 ppm. In such an......
  • 2-butene (chemical compound)
    any of four isomeric compounds belonging to the series of olefinic hydrocarbons. The chemical formula is C4H8. The isomeric forms are 1-butene, cis-2-butene, trans-2-butene, and isobutylene. All four butenes are gases at room temperature and pressure....
  • 2-chloro-1,3-butadiene (chemical compound)
    Alkyne polymerization is not nearly as developed nor as useful a procedure as alkene polymerization. The dimer of acetylene, vinylacetylene, is the starting material for the preparation of 2-chloro-1,3-butadiene, which in turn is polymerized to give the elastomer neoprene. Neoprene was the first commercially successful rubber substitute....
  • 2-chloro-2-methylpropane (chemical compound)
    ...only when the alkyl halide is primary. The principal reaction observed when a strong base reacts with a secondary or tertiary alkyl halide is elimination, as in the attack of sodium methoxide on 2-chloro-2-methylpropane....
  • 2-hydroxy-3-naphthanilide (chemical compound)
    ...fabric (see above Dyeing techniques: Azo dyeing techniques). Since the process was done at ice temperature, some dyes were called ice colours. In 1912 it was found that 2-hydroxy-3-naphthanilide (Naphtol AS, from the German Naphtol Anilid Säure) forms a water-soluble anion with affinity for cotton, a major step in the development of the ingrai...
  • 2-hydroxyethyl methacrylate (chemical compound)
    Related in structure to methyl methacrylate are the monomers 2-hydroxyethyl methacrylate and methyl cyanoacrylate, denoted by the chemical formulas...
  • 2-hydroxypropanoic acid (chemical compound)
    an organic compound belonging to the family of carboxylic acids, present in certain plant juices, in the blood and muscles of animals, and in the soil. It is the commonest acidic constituent of fermented milk products such as sour milk, cheese, and buttermilk....
  • 2-hydroxypropionic acid (chemical compound)
    an organic compound belonging to the family of carboxylic acids, present in certain plant juices, in the blood and muscles of animals, and in the soil. It is the commonest acidic constituent of fermented milk products such as sour milk, cheese, and buttermilk....
  • 2-keto-3-deoxy-6-phosphogluconate (chemical compound)
    ...(derived from glucose via steps [1] and [12]) is not oxidized to ribulose 5-phosphate via reaction [13] but, in an enzyme-catalyzed reaction [14], loses water, forming the compound 2-keto-3-deoxy-6-phosphogluconate (KDPG)....
  • 2-methyl-1-propanol (chemical compound)
    any of four organic compounds having the same molecular formula but different structures: normal (n-) butyl alcohol, secondary (sec-) butyl alcohol, isobutyl alcohol, and tertiary (t-) butyl alcohol....
  • 2-methyl-1,3-butadieneisoprene (chemical compound)
    a colourless, volatile liquid hydrocarbon obtained in processing petroleum or coal tar and used as a chemical raw material. The formula is C5H8....
  • 2-methyl-2-propanol (chemical compound)
    ...of four organic compounds having the same molecular formula but different structures: normal (n-) butyl alcohol, secondary (sec-) butyl alcohol, isobutyl alcohol, and tertiary (t-) butyl alcohol....
  • 2-methyl-3-butadiene (chemical compound)
    a colourless, volatile liquid hydrocarbon obtained in processing petroleum or coal tar and used as a chemical raw material. The formula is C5H8....
  • 2-methylbenzenol (chemical compound)
    any of the three methylphenols with the same molecular formula but having different structures: ortho- (o-) cresol, meta- (m-) cresol, and para- (p-) cresol....
  • 2-methylpropene (chemical compound)
    ...compounds belonging to the series of olefinic hydrocarbons. The chemical formula is C4H8. The isomeric forms are 1-butene, cis-2-butene, trans-2-butene, and isobutylene. All four butenes are gases at room temperature and pressure....
  • 2-[p-chloro-α-(2-dimethylaminoethyl) benzyl]pyridine (2-dimethylaminoethyl)
    synthetic drug used to counteract the histamine reaction, as in allergies. Chlorpheniramine, introduced into medicine in 1951, is administered orally or by intravenous, intramuscular, or subcutaneous injection in the form of chlorpheniramine maleate. It is effective in controlling the symptoms of hay fever, acute skin reactions (such as ...
  • 2-propanol (chemical compound)
    one of the most common members of the alcohol family of organic compounds. Isopropyl alcohol was the first commercial synthetic alcohol. It is easily synthesized from the reaction of propylene with sulfuric acid, followed by hydrolysis....
  • 2-propanone (chemical compound)
    organic solvent of industrial and chemical significance, the simplest and most important of the aliphatic (fat-derived) ketones. Pure acetone is a colourless, somewhat aromatic, flammable, mobile liquid that boils at 56.2 °C (133 °F)....
  • 2-propenal (chemical compound)
    As another example, the common name of CH2=CHCHO, for which the IUPAC name is 2-propenal, is acrolein, a name derived from that of acrylic acid, the parent carboxylic acid....
  • 2-tone (music)
    In several regional British cities, the distinct late 1970s combination of economic turmoil, unemployment benefits (effectively an arts subsidy), and art school punks resulted in a generation of eccentric talent. In Coventry, the southernmost centre of Britain’s Midlands engineering belt, the outcome was 2-Tone, a mostly white take on ska, the music brought to Britain by Jamaican immigrants...
  • 20 (number)
    The number 20 has little mystical significance, but it is historically interesting because the Mayan number system used base 20. When counting time the Maya replaced 20 × 20 = 400 by 20 × 18 = 360 to approximate the number of days in the year. Many old units of measurement involve 20 (a score)—for example, 20 shillings to...
  • 20/20 (American television program)
    ...network news program and, with a salary of $1 million per year, the highest-paid journalist at that time. In 1978 she left the program. The following year she joined the ABC newsmagazine show 20/20 as correspondent, becoming cohost with Downs in 1984; she remained with the program until 2004....
  • 200-metre race (running race)
    American sprinter who held the world record for the 200-metre dash with turn (1966–71), his best time being 19.83 sec—the first time that the distance was run in less than 20 sec. He also held the record for the straightaway 200-metre dash (1965–79), his best time being 19.5 sec....
  • 2000 Academy Awards (awarded 2001)
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  • 2000 ad (British comic)
    ...were young, as was the case in popular music and film, to which comics were often linked. The transition from the juvenile to the “young adult” market is exemplified in Britain’s 2000 ad, which flourished from 1978 to 1985 (and continues in the 21st century at a lower circulation level), was reprinted in the United States, and at its peak sold 120...
  • 20,000 Leagues Under the Sea (film by Fleischer [1954])
    ...Color: Milton Krasner for Three Coins in the FountainArt Direction, Black-and-White: Richard Day for On the WaterfrontArt Direction, Color: John Meehan for 20,000 Leagues Under the SeaMusic Score of a Dramatic or Comedy Picture: Dimitri Tiomkin for The High and the MightyScoring of a Musical Picture: Saul Chaplin and......
  • 2001: A Space Odyssey (film by Kubrick [1968])
    Stanley Kubrick’s hugely successful film 2001: A Space Odyssey (1968) was based on Clarke’s short story The Sentinel (1951), which Clarke and Kubrick subsequently developed into a novel (1968), published under the same name as the movie. A sequel novel, 2010: Odyssey Two (1982), by Clarke alone, was released ...
  • 2001 Academy Awards (awarded 2002)
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  • 2002 Academy Awards (awarded 2003)
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  • 2003 Academy Awards (awarded 2004)
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  • 2003 EL61 (dwarf planet)
    unusual dwarf planet orbiting the Sun in the Kuiper belt beyond Pluto. It was discovered in 2003 by a team of American astronomers at Cerro Tololo Inter-American Observatory. Originally called 2003 EL61, Haumea is named for the Hawaiian goddess of birth and fertility. Haumea is an elongated object, unusu...
  • 2003 UB313 (astronomy)
    large, distant body of the solar system, revolving around the Sun well beyond the orbits of Neptune and Pluto in the Kuiper belt. It was discovered in 2005 in images taken two years earlier at Palomar Observatory in California, U.S. Before it received its official name, Eris was known by the provisional designation 2003 UB...
  • 2004 Academy Awards (awarded 2005)
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  • 2005 Academy Awards (awarded 2006)
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  • 2005 FY9 (dwarf planet)
    dwarf planet orbiting the Sun beyond the orbit of Pluto. Originally called 2005 FY9, Makemake is named after the creator god of the Polynesian inhabitants of Easter Island; the name alludes to its discovery by astronomers at Palomar Observatory on March 31, 2005, a few days after Easter...
  • 2006 Academy Awards (awarded 2007)
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  • 2007 Academy Awards (awarded 2008)
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  • 2010: Odyssey Two (novel by Clarke)
    ...The Sentinel (1951), which Clarke and Kubrick subsequently developed into a novel (1968), published under the same name as the movie. A sequel novel, 2010: Odyssey Two (1982), by Clarke alone, was released as a film in 1984. In 1997 he published 3001: The Final Odyssey. Clarke was knighted in 2000....
  • 2060 Chiron (astronomy)
    icy small body orbiting the Sun in the outer solar system. Once thought to be the most distant known asteroid, it is now believed to have the composition of a comet nucleus—i.e., a mixture of water ice, frozen gases, and dust....
  • 20th Century-Fox Film Corporation (American company)
    major American motion-picture studio, formed in 1935 by the merger of Twentieth Century Pictures and the Fox Film Corporation. The latter company was founded in 1915 by William Fox, a New York City exhibitor who had begun distributing films in 1904 and producing them in 1913. In 1915 Fox moved his studio to Los Angeles and named it the Fox Film Corporation. In 1927 the company ...
  • 21-centimetre radiation
    electromagnetic radiation of radio wavelength emitted by cold, neutral, interstellar hydrogen atoms. The hydrogen atom is composed of a positively charged particle, the proton, and a negatively charged particle, the electron. These particles have some intrinsic angular momentum called spin. (However, this spin is not an actual physical rotation; it is, rather, a quantum mechanic...
  • 21-hydroxylase (enzyme)
    The most common type of congenital adrenal hyperplasia is deficiency of 21-hydroxylase, an enzyme that stimulates one of the last steps in cortisol synthesis. Excess androgen produced to overcome this deficiency during fetal life results in virilization—the development of masculine-appearing external genitalia in newborn girls and precocious sexual development in boys—that becomes......
  • 212 Squadron (United States military unit)
    ...General Claire L. Chennault’s American Volunteer Group, the Flying Tigers, in China. After the Japanese attack on Pearl Harbor, he rejoined the Marines in 1942 and organized Squadron 214, called the Black Sheep Squadron, one of the most renowned fighting units of the war, operating mostly in the Solomon Islands. On his last mission, on January 3, 1944, he shot down three Japanese aircraf...
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