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alphanumeric
alphanumeric or alphameric , the set of letters and numbers. When used in reference to computer input and output, the set usually is expanded to include the upper- and lower-case alphabetic characters (A-Z, a-z), the numeric characters (0-9), and special characters (such as the symbols $, #, a...
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Antares
Antares , brightest star in the constellation Scorpius ; Bayer designation Alpha Scorpii; 1992 position R.A. 16 h 27.6 m , Dec. -26°22′. A red supergiant of spectral class M1, Antares has an apparent magnitude of about 0.9, making it one of the 20 brightest stars in the sky. Its name ...
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civil time
civil time local time based on universal time . Civil time may be formally defined as mean solar time plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon. Civil time is occasionally adjusted by one-second increments to ensure that the difference between a unif...
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Cerro Tololo Inter-American Observatory
Cerro Tololo Inter-American Observatory , astronomical observatory located on Cerro Tololo peak, Chile, with offices in La Serena, about 40 mi (64 km) to the west. Funded by the U.S. National Science Foundation (NSF), it is operated by the Association of Universities for Research in Astronomy (AUR...
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barometer
barometer , instrument for measuring atmospheric pressure. It was invented in 1643 by the Italian scientist Evangelista Torricelli, who used a column of water in a tube 34 ft (10.4 m) long. This inconvenient water column was soon replaced by mercury, which is denser than water and requires a tube ab...
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Durban
Durban , city (1991 pop. 473,826), KwaZulu-Natal, E South Africa, on Natal Bay, an arm of the Indian Ocean. Durban is an industrial center, a major seaport, and a year-round resort. Industries include sugar refining, shipbuilding and ship repairing, petroleum refining, fishing, automobile assembly, ...
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Kitt Peak National Observatory
Kitt Peak National Observatory astronomical observatory located southwest of Tucson, Ariz.; it was founded in 1958 under contract with the National Science Foundation and is administered by the Association of Universities for Research in Astronomy. Its principal instrument is the Mayall 158-in. (...
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seaborgium
seaborgium , artificially produced radioactive chemical element; symbol Sg; at. no. 106; mass number of most stable isotope 266; m.p., b.p., sp. gr., and valence unknown. Situated in Group 6 of the periodic table , it is expected to have properties similar to those of tungsten .
The discovery...
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catfish
catfish common name applied to members of the freshwater fish families constituting the suborder Nematognathi. The catfish is related to the sucker and the minnow , and like them has a complex set of bones forming a sensitive hearing apparatus. Catfish are named for the barbels ( "whiskers" ) ...
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competition
competition in economics, rivalry in supplying or acquiring an economic service or good. Sellers compete with other sellers, and buyers with other buyers. In its perfect form, there is competition among many small buyers and sellers, none of whom is too large to affect the market as a whole; in pra...
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