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atmosphere

(Encyclopedia)CE5 Atmosphere atmosphere [Gr.,=sphere of air], the mixture of gases surrounding a celestial body with sufficient gravity to maintain it. Although some details about the atmospheres of other plane...

seeing

(Encyclopedia)seeing, in astronomy, the clarity with which stars and other celestial objects can be observed. It is primarily determined by the atmosphere of the earth. The most obvious phenomenon is twinkling, whe...

muffler

(Encyclopedia)muffler, in automobiles, device designed to reduce the noise from the exhaust of an internal-combustion engine. When the exhaust gases from an internal-combustion engine are released directly into the...

geochemistry

(Encyclopedia)geochemistry, study of the chemical changes on the earth. More specifically, it is the study of the absolute and relative abundances of chemical elements in the minerals, soils, ores, rocks, water, an...

meteor

(Encyclopedia)meteor, appearance of a small particle flying through space that interacts with the earth's upper atmosphere. While still outside the atmosphere, the particle is known as a meteoroid. Countless meteor...

carbon cycle

(Encyclopedia)CE5 Carbon cycle carbon cycle, in biology, the exchange of carbon between living organisms and the nonliving environment. Inorganic carbon dioxide in the atmosphere is converted by plants into sim...

Titan , in astronomy

(Encyclopedia)Titan tīˈtən [key], in astronomy, the largest of the named moons, or natural satellites, of Saturn. Also known as Saturn VI (or S6), Titan is 3,200 mi (5,150 km) in diameter, orbits Saturn at a mea...

solar constant

(Encyclopedia)solar constant, the average amount of radiant energy received by the earth's atmosphere from the sun; its value is about 2 calories per min incident on each square centimeter of the upper atmosphere. ...

Van Allen radiation belts

(Encyclopedia)CE5 Van Allen radiation belts: The solar wind, a stream of protons, electrons, and ions coming from the sun, gives the belts their asymmetrical shape. Van Allen radiation belts, belts of radiation...

Keeling, Charles David

(Encyclopedia)Keeling, Charles David, 1928–2005, U.S. geochemist, b. Scranton, Pa., Ph.D. Northwestern Univ., 1954. As a postdoctoral fellow at the California Institute of Technology (1953–56), he developed a s...