Article: Doppler effect
The Columbia Encyclopedia, Sixth Edition;      356 words ......Austrian scientist Christian Doppler, who demonstrated the effect...stationary listener. The Doppler effect in reflected radio waves is employed in radar to...surveillance. In astronomy, the Doppler effect for light is used to measure...the Doppler effect for ...

Article: radio
World Encyclopedia;      291 words ......electromagnetic radiation in the form of radio waves. A transmitter generates a radio signal...modulation, to retrieve the signal. Radio waves travel at the speed of light and are...UHF) and very high frequency (VHF) radio waves used to send signals for television...

Article: radio astronomy
The Columbia Encyclopedia, Sixth Edition;      700+ words ......and absorb naturally. Radio Telescopes Radio waves emanating from celestial bodies are...telescope. This dish serves to focus the radio waves into a concentrated signal that is then...rotation of the earth. Galactic Sources of Radio Waves Naturally occurring radio emission from...

Article: Doppler Effect
Science of Everyday Things;      700+ words ...DOPPLER EFFECT CONCEPT Almost everyone has experienced the Doppler effect, though perhaps without knowing what causes it...lowers perceptibly. This is an example of the Doppler effect: the change in the observed frequency of a wave...

Article: VHF
The Oxford Pocket Dictionary of Current English;      23 words ...VHF • abbr. very high frequency, denoting radio waves of a frequency of about 30–300 MHz and a wavelength of about 1–10 meters.

Article: Grote Reber
Encyclopedia of World Biography;      700+ words ......describing how he had detected the first radio waves from outer space. Reber read Jansky...stars emitted energy in the form of radio waves, as well as light waves. Jansky followed...another report in 1935 which linked the radio waves to the distribution of the Milky Way...

Article: radio waves
A Dictionary of Astronomy;      51 words ...radio waves Electromagnetic radiation of wavelength longer than about 1 mm (30 GHz). The longest radio waves observable by radio astronomers have a wavelength of about 30 m (10 MHz) (see radio window ). The shortest radio...

Article: Seeing
World of Earth Science;      688 words ......light, the near infrared, microwaves and radio waves with wavelengths between about 0.35...ultraviolet light, x rays, gamma rays, and radio waves with wavelengths greater than 1 m. The...water and molecular oxygen, while long radio waves are absorbed by ions high in the earth...

Article: magnetic resonance imaging
The Columbia Encyclopedia, Sixth Edition;      183 words ......magnetically. The patient is then subjected to radio waves, which cause the aligned nuclei to flip ; when the radio waves are withdrawn the nuclei return to their original positions, emitting radio waves that are then detected by a receiver and...

Article: antenna
A Dictionary of Astronomy;      123 words ...antenna A device used in radio astronomy to detect radio waves; also known as an aerial . In an antenna, radio waves induce an oscillating electric current in a conductor...resolution. Antennas may also be used to transmit radio waves.

Article: ultra high frequency
World Encyclopedia;      27 words ...ultra high frequency ( UHF ) Radio waves in the frequency band 300–3000MHz. UHF waves have a wavelength of c. 1m (3ft) or less, and are used for television broadcasting .

Article: An Effective Treatment Alternative for Cancer, Osteoporosis & Kidney Disease: GEMM Therapy Unveiled.
Business Wire;  October 1, 2007 ;     700+ words ......molecules primarily communicate via radio waves which is the universal language of the...reactions. By externally applying comparable radio waves, it is possible to intervene with the...We have been extensively utilizing radio waves in all kinds of communications such...

Article: radar astronomy
The Columbia Encyclopedia, Sixth Edition;      237 words ......as rotation rates. A short burst of radio waves is transmitted in the direction of the...under study. The object reflects the radio waves back to earth, where they are detected...precisely measured electronically. Since radio waves travel with the speed of light, the...

Article: Japanese Mobile Phone Operators Find No Adverse Health Effects from Base Station Radio Waves.
JCN Newswires;  January 24, 2007 ;     700+ words ......collaborating to examine the effects of radio waves. As part of the collaboration, large-sca...the cellular and genetic level using radio waves up to 10 times stronger than the limit...not find adverse health effects from radio waves from mobile phone base stations. The...