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Bode, Johann Elert

(Encyclopedia)Bode, Johann Elert yōˈhän āˈlĕrt bōˈdə [key], 1747–1826, German astronomer. From 1772 to 1825 he was astronomer of the Academy of Science, Berlin, and from 1786, director of the Berlin Obse...

Ra, in Egyptian religion

(Encyclopedia)Ra rā [key], in Egyptian religion, sun god, one of the most important gods of ancient Egypt. Ra was chief of the cosmic deities and was sometimes called the creator and father of all things. Early Eg...

raffia

(Encyclopedia)raffia rāˈfēə [key], fiber obtained from the raffia palm of Madagascar, exported for various uses, such as tying up plants that require support, binding together vegetables to be marketed, and wea...

actinometer

(Encyclopedia)actinometer ăkˌtənŏmˈətər [key], instrument used to measure the heating power of radiation. Actinometers are used chiefly in meteorology to measure solar radiation as transmitted directly by th...

sky

(Encyclopedia)sky, apparent dome over the earth, background of the clouds, sun, moon, and stars. The blue color of the clear daytime sky results from the selective scattering of light rays by the minute particles o...

stratosphere

(Encyclopedia)stratosphere strătˈəsfēr [key], second lowest layer of the earth's atmosphere. The level from which it extends outward varies with latitude; it begins c.51⁄2 mi (9 km) above the poles, c.6 or 7 ...

transit

(Encyclopedia)transit, in astronomy, passage of a body across a meridian or passage of a small body across the visible disk of a larger one. (The passage of a large body across a smaller one is called an eclipse or...

astronomy

(Encyclopedia)astronomy, branch of science that studies the motions and natures of celestial bodies, such as planets, stars, and galaxies; more generally, the study of matter and energy in the universe at large. ...

Pluto, in astronomy

(Encyclopedia)Pluto, in astronomy, a dwarf planet and the first Kuiper belt, or transneptunian, object (see comet) to be discovered (1930) by astronomers. Pluto has an elliptical orbit usually lying beyond that of ...

Deneb

(Encyclopedia)Deneb dĕnˈĕb [key], brightest star in the constellation Cygnus; Bayer designation Alpha Cygni; 1992 position R.A. 20h41.2m, Dec. +45°15′. It is a white supergiant of spectral class A2 Ia; its in...