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Sun Yat-sen

(Encyclopedia)Sun Yat-sen so͞on yät-sĕn [key], Mandarin Sun Wen, 1866–1925, Chinese revolutionary. He was born near Guangzhou into a farm-owning family. He attended (1879–82) an Anglican boys school in Honol...

earth, in geology and astronomy

(Encyclopedia)CE5 A. Cross section of the earth, showing its shells B. Detailed cross section of the crust and upper mantle: The lithosphere consists of the hard rock in the crust and upper mantle, lying above t...

ether, in physics and astronomy

(Encyclopedia)ether or aether, in physics and astronomy, a hypothetical medium for transmitting light and heat (radiation), filling all unoccupied space; it is also called luminiferous ether. In Newtonian physics a...

opposition

(Encyclopedia)opposition, in astronomy, alignment of two celestial bodies on opposite sides of the sky as viewed from earth. Opposition of the moon or planets is often determined in reference to the sun. Only the s...

quadrature

(Encyclopedia)quadrature, in astronomy, arrangement of two celestial bodies at right angles to each other as viewed from a reference point. If the reference point is the earth and the sun is one of the bodies, a pl...

radial velocity

(Encyclopedia)radial velocity, in astronomy, the speed with which a star moves toward or away from the sun. It is determined from the red or blue shift in the star's spectrum. ...

Shklovsky, Iosif Samuilovich

(Encyclopedia)Shklovsky, Iosif Samuilovich yôsˈĭf səmo͞oēlˈəvĭch shklŏfˈskē [key], 1916–85, Soviet astronomer. He was head of the department of radio-astronomy at the Sternberg Astronomical Institute,...

infrared astronomy

(Encyclopedia)infrared astronomy, study of celestial objects by means of the infrared radiation they emit, in the wavelength range from about 1 micrometer to about 1 millimeter. All objects, from trees and building...

neutrino astronomy

(Encyclopedia)neutrino astronomy, study of stars by means of their emission of neutrinos, fundamental particles that result from nuclear reactions and are emitted by stars along with light. Approximately 100 billio...

ultraviolet astronomy

(Encyclopedia)ultraviolet astronomy, study of celestial objects by means of the ultraviolet radiation they emit, in the wavelength range from about 90 to about 350 nanometers. Ultraviolet (UV) line spectrum measure...