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Vesta, in astronomy

(Encyclopedia)Vesta vĕsˈtə [key], in astronomy, the fourth asteroid to be discovered. It was found in 1807 by H. Olbers. It is the third largest asteroid in size, with a diameter of c.326 mi (525 km). Its averag...

communications satellite

(Encyclopedia)communications satellite artificial satellite that functions as part of a global radio-communications network. Echo 1, the first communications satellite, launched in 1960, was an instrumented inflat...

isolationism

(Encyclopedia)isolationism, a national policy of abstaining from political, military, or economic alliances or agreements with other countries. Isolationism may be adopted in order to devote a country's energies to...

mandates

(Encyclopedia)mandates, system of trusteeships established by Article 22 of the Covenant of the League of Nations for the administration of former Turkish territories and of former German colonies. As finally adopt...

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. ...

tide

(Encyclopedia)tide, alternate and regular rise and fall of sea level in oceans and other large bodies of water. These changes are caused by the gravitational attraction of the moon and, to a lesser extent, of the s...

conservatism

(Encyclopedia)conservatism, in politics, the desire to maintain, or conserve, the existing order. Conservatives value the wisdom of the past and are generally opposed to widespread reform. Modern political conserva...

Japanese

(Encyclopedia)Japanese jăpˌənēzˈ [key], language of uncertain origin that is spoken by more than 125 million people, most of whom live in Japan. There are also many speakers of Japanese in the Ryukyu Islands, ...

cycle

(Encyclopedia)cycle, in astronomy, period of time required for the recurrence of some celestial event. The length of a cycle may be measured relative to the sun or to the fixed stars (see sidereal time). A frequent...