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magnetron

(Encyclopedia)magnetron măgˈnĭtrŏnˌ [key], vacuum tube oscillator (see electron tube) that generates high-power electromagnetic signals in the microwave frequency range. Its operation is based on the combined ...

transept

(Encyclopedia)transept trănˈsĕptˌ [key], term applied to the transverse portion of a building cutting its main axis at right angles or to each arm of such a portion. Transepts are found chiefly in churches, whe...

Bose, Subhas Chandra

(Encyclopedia)Bose, Subhas Chandra sho͝obhäshˈ chŭnˈdrə bōs [key], 1897–1945?, Indian nationalist also known as Netaji. He began his political career in Calcutta (now Kolkata) and soon became the leader of...

orbit

(Encyclopedia)CE5 Important points in a planet's orbit as seen from the earth orbit, in astronomy, path in space described by a body revolving about a second body where the motion of the orbiting bodies is domi...

crystal

(Encyclopedia)CE5 Types of crystal crystal, a solid body bounded by natural plane faces that are the external expression of a regular internal arrangement of constituent atoms, molecules, or ions. The formation...

analytic geometry

(Encyclopedia)analytic geometry, branch of geometry in which points are represented with respect to a coordinate system, such as Cartesian coordinates, and in which the approach to geometric problems is primarily a...

Phoebe, in astronomy

(Encyclopedia)Phoebe fēˈbē [key], in astronomy, one of the named moons, or natural satellites, of Saturn. Also known as Saturn IX (or S9), Phoebe is 137 mi (220 km) in diameter, orbits Saturn at a mean distance ...

apsis

(Encyclopedia)CE5 Apsis points, or apsides, in the earth's orbit: At perihelion the earth is closest to the sun and at aphelion it is farthest from the sun. apsis (pl. apsides), point in the orbit of a body whe...

seafloor spreading

(Encyclopedia)CE5 Schematic model of the oceanic crust, showing seafloor spreading seafloor spreading, theory of lithospheric evolution that holds that the ocean floors are spreading outward from vast underwate...

Hertzsprung-Russell diagram

(Encyclopedia)CE5 The Hertzsprung-Russell diagram shows the relation between the luminosity and surface temperature (which is related to spectral class, or color) of the stars in the Milky Way. Most stars fall a...