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Amenhotep III

(Encyclopedia)Amenhotep III ăˌmĕnōˈfĭs [key], d. c.1372 b.c., king of ancient Egypt, of the XVIII dynasty. He succeeded his father, Thutmose IV, c.1411 b.c. His reign marks the culmination and the start of th...

geomorphology

(Encyclopedia)geomorphology, study of the origin and evolution of the earth's landforms, both on the continents and within the ocean basins. It is concerned with the internal geologic processes of the earth's crust...

month

(Encyclopedia)month, in chronology, the conventional period of a lunation, i.e., passage of the moon through all its phases. It is usually computed at approximately 29 or 30 days. For the computation of the month a...

Laplace, Pierre Simon, marquis de

(Encyclopedia)Laplace, Pierre Simon, marquis de pyĕr sēmôNˈ märkēˈ də läpläsˈ [key], 1749–1827, French astronomer and mathematician. At 18 he went to Paris, proved his gift for mathematical analysis to...

radar astronomy

(Encyclopedia)radar astronomy, application of radar to the determination of distances and planetary features within the solar system, such as rotation rates. A short burst of radio waves is transmitted in the direc...

radar

(Encyclopedia)radar, system or technique for detecting the position, movement, and nature of a remote object by means of radio waves reflected from its surface. Although most radar units use microwave frequencies, ...

power, electric

(Encyclopedia)power, electric, energy dissipated in an electrical or electronic circuit or device per unit of time. The electrical energy supplied by a current to an appliance enables it to do work or provide some ...

Dick, Philip K.

(Encyclopedia)Dick, Philip K. (Philip Kindred Dick), 1928–82, American science-fiction writer, b. Chicago. Dick often wrote of the psychological states of individuals caught in altered realities where the everyda...

Ericsson, John

(Encyclopedia)Ericsson, John ĕrˈĭksən [key], 1803–89, Swedish-American inventor and marine engineer, b. Värmlands co., Sweden. He moved to London in 1826, and entered the railroad locomotive Novelty in a con...

geophysics

(Encyclopedia)geophysics, study of the structure, composition, and dynamic changes of the earth, its atmosphere, hydrosphere and magnetosphere, based on the principles of physics. The term was probably first used i...