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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...

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...

Enceladus

(Encyclopedia)Enceladus ĕnsĕlˈədəs [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn II (or S2), Enceladus is 310 mi (500 km) in diameter, orbits Saturn at a m...

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...

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 ...

McEwan, Ian

(Encyclopedia)McEwan, Ian (Ian Russell McEwan) məkyo͞oˈən [key], 1948–, English novelist, b. Aldershot, B.A. Univ. of Sussex, 1970, M.A. Univ. of East Anglia, 1971. His early short-story collections, First Lo...

Musk, Elon

(Encyclopedia)Musk, Elon ēˈlŏn [key], 1971–, American business executive and entrepreneur, b. Pretoria...

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...