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matter

(Encyclopedia)matter, anything that has mass and occupies space. Matter is sometimes called koinomatter (Gr. koinos=common) to distinguish it from antimatter, or matter composed of antiparticles. The atomic th...

cosmology

(Encyclopedia)cosmology, area of science that aims at a comprehensive theory of the structure and evolution of the entire physical universe. The earliest pre-Ptolemaic theories assumed that the earth was the cent...

rocket, in aeronautics

(Encyclopedia)CE5 Relative positions of the components of the Saturn V rocket, the U.S. space vehicle used in the moon missions rocket, any vehicle propelled by ejection of the gases produced by combustion of s...

Hitler, Adolf

(Encyclopedia)Hitler, Adolf äˈdôlf hĭtˈlər [key], 1889–1945, founder and leader of National Socialism (Nazism), and German dictator, b. Braunau in Upper Austria. By July, 1944, the German military si...

Korea

(Encyclopedia)CE5 Korea kôrēˈə, kə– [key], Korean Hanguk or Choson, region and historic country (85,049 sq mi/220,277 sq km), E Asia. A peninsula, 600 mi (966 km) long, Korea separates the Sea of Japan (c...

Somalia

(Encyclopedia)CE5 Somalia sōmäˈleə [key], officially Federal Republic of Somalia, country (2015 est. pop. 10,616,000), 246,200 sq mi (637,657 sq km), extreme E Africa. It is directly south of the Arabian pen...

planet

(Encyclopedia)planet [Gr.,=wanderer], a large nonluminous body of rock, gas, or ice that orbits the sun or another star, has a rounded shape due to gravity, and has cleared its orbit of smaller objects. The term, o...

Kurds

(Encyclopedia)Kurds kûrds, ko͝ords [key], a non-Arab Middle Eastern minority population that inhabits the region known as Kurdistan, an extensive plateau and mountain area, c.74,000 sq mi (191,660 sq km), in SW A...

atom

(Encyclopedia)CE5 Bohr-Rutherford atom CE5 Probability distribution of the electron in the hydrogen atom: A. Ground state B. Highly excited state atom [Gr.,=uncuttable (indivisible)], basic unit of matte...

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 ...