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Turing machine

(Encyclopedia)Turing machine, a mathematical model of a device that computes via a series of discrete steps and is not limited in use by a fixed maximum amount of data storage. Introduced by the British mathematici...

osprey

(Encyclopedia)osprey ŏsˈprē [key], common name for a fish-eating bird of prey found near water in most parts of the world. The osprey, or fish hawk, Pandion haliaetus, has brown upperparts and a grayish white he...

coast protection

(Encyclopedia)coast protection, methods used to protect coastal lands from erosion. Beaches can exist only where a delicate dynamic equilibrium exists between the amount of sand supplied to the beach and the inevit...

apsis

(Encyclopedia)CE5 Apsis points, or apsides, in the earth's orbit: At perihelion the earth is closest to the sun and at aphelion it is farthest from the sun. apsis (pl. apsides), point in the orbit of a body whe...

Eris, in astronomy

(Encyclopedia)Eris, in astronomy, the largest known dwarf planet. Eris, whose highly eccentric elliptical orbit ranges from 38 AU to 97 AU and is inclined more than 44°, is the largest known object of the Kuiper b...

Hyperion, in astronomy

(Encyclopedia)Hyperion hīpērˈēən [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn VII (or S7), Hyperion is the largest highly irregular (nonspherical) body in...

Phoebe, in astronomy

(Encyclopedia)Phoebe fēˈbē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IX (or S9), Phoebe is 137 mi (220 km) in diameter, orbits Saturn at a mean distance ...

Prometheus, in astronomy

(Encyclopedia)Prometheus prōmēˈthēəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn XVI (or S16), Prometheus is an irregularly shaped (nonspherical) body me...

Ban, Shigeru

(Encyclopedia)Ban, Shigeru, 1957–, Japanese architect. After graduating (1984) from the Cooper Union School of Architecture, New York City, he established (1985) a practice in Tokyo, later adding offices in Paris...

space law

(Encyclopedia)space law, agreements governing the exploration and use of outer space, developed since the first launching (1957) by humans of a satellite into space. Space law, an aspect of international law, has g...