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radar astronomy

(Encyclopedia)radar astronomy, application of radar to the determination of distances and planetary features within the solar system, such as rotation rates. A short burst of radio waves is transmitted in the direc...

antenna

(Encyclopedia)antenna ăntĕnˈə [key], in electronics, system of wires or other conductors used to transmit or receive radio or other electromagnetic waves (see radio); sometimes called an aerial. The idea of usi...

pulsar

(Encyclopedia)pulsar, in astronomy, a neutron star that emits brief, sharp pulses of energy instead of the steady radiation associated with other natural sources. The study of pulsars began when Antony Hewish and h...

citizens band radio

(Encyclopedia)citizens band radio: see radio.

Radio Free Europe

(Encyclopedia)Radio Free Europe (RFE), broadcasting organization established in 1950 with the stated mission of promoting democratic values and institutions. Its original purpose was to broadcast news to countries ...

Radio Frequencies (table)

(Encyclopedia)Radio Frequencies

radio-frequency identification

(Encyclopedia)radio-frequency identification (RFID), a technology that uses radio waves to transmit data and uniquely identify an animal, person, or thing. An RFID system typically consists of a tag and a reader. T...

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,...

interference

(Encyclopedia)CE5 Constructive interference: Two crests or two troughs meet and combine (A, B, C). Destructive interference: A crest and a trough meet and cancel each other (D, E, F). interference, in physics, ...

X-ray astronomy

(Encyclopedia)X-ray astronomy, study of celestial objects by means of the X rays they emit, in the wavelength range from 0.01 to 10 nanometers. X-ray astronomy dates to 1949 with the discovery that the sun emits X ...