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gamma radiation

(Encyclopedia)gamma radiation, high-energy photons emitted as one of the three types of radiation resulting from natural radioactivity. It is the most energetic form of electromagnetic radiation, with a very short ...

joint, in anatomy

(Encyclopedia)joint, in anatomy, juncture between two bones. Some joints are immovable, e.g., those that connect the bones of the skull, which are separated merely by short, tough fibers of cartilage. Movable joint...

Mayne, Thom

(Encyclopedia)Mayne, Thom, 1944–, American architect, b. Waterbury, Conn., grad. Univ. of Southern California (B.A., 1968), Harvard (M.A., 1978). In 1972 Mayne cofounded the firm Morphosis in Santa Monica, Calif....

Musk, Elon

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

ceramics

(Encyclopedia)ceramics sərămˈĭks [key], materials made of nonmetallic minerals that have been permanently hardened by firing at a high temperature, or objects made of such materials. Most ceramics resist heat a...

celestial mechanics

(Encyclopedia)celestial mechanics, the study of the motions of astronomical bodies as they move under the influence of their mutual gravitation. Celestial mechanics analyzes the orbital motions of planets, dwarf pl...

transmutation of elements

(Encyclopedia)transmutation of elements, conversion of one chemical element into another. The expression has both historical and contemporary significance. The transmutation of certain metals into gold by means of ...

blazonry

(Encyclopedia)blazonry blāˈzənrē [key], science of describing or depicting armorial bearings. The introduction, since the Middle Ages, of artificial rules and fanciful medieval terms has complicated the science...

biology

(Encyclopedia)biology, the science that deals with living things. It is broadly divided into zoology, the study of animal life, and botany, the study of plant life. Subdivisions of each of these sciences include cy...

sextant

(Encyclopedia)CE5 Sextant sextant, instrument for measuring the altitude of the sun or another celestial body; such measurements can then be used to determine the observer's geographical position or for other n...