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Dawn Chorus (electromagnetic)
The electromagnetic dawn chorus is a phenomenon that occurs most often at or shortly after dawn local time. With the proper radio equipment, dawn chorus can be converted to sounds that resemble birds' dawn chorus (by coincidence). The electromagnetic dawn chorus is believed to be generated by a Doppler-shifted cyclotron interaction between anisotropic distributions of energetic (> 40 keV) electrons and ambient background VLF noise. These energetic electrons are generally injected into the inner magnetosphere at the onset of the substorm expansion phase. Dawn choruses occur more frequently during magnetic storms. This phenomenon also occurs during aurorae, when it is termed an auroral chorus. See also * Auroral chorus *Hiss (electromagnetic) *Whistler (radio) * Cluster One, a Pink Floyd track using sferics A radio atmospheric signal or sferic (sometimes also spelled "spheric") is a broadband electromagnetic impulse that occurs as a result of natural atmospheric light ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chorus Electromagnetic Palmer 2003-02-27 T085030
Chorus may refer to: Music * Chorus (song) or refrain, line or lines that are repeated in music or in verse * Chorus effect, the perception of similar sounds from multiple sources as a single, richer sound * Chorus form, song in which all verses or stanzas are sung to the same music * Choir, a vocal ensemble * ''Chorus'' (Eberhard Weber album), a 1985 album by jazz composer Eberhard Weber * ''Chorus'' (Erasure album), a 1991 album by English musical duo Erasure ** "Chorus" (Erasure song), a 1991 single from the album * ''Chorus'' (Flying Saucer Attack album), an album by the band Flying Saucer Attack * Chorus UK, a community choir in Sheffield, UK Other entertainment * Greek chorus, a group of performers in the plays of classical Greece who comment on the dramatic action * Chorus (musical theatre), non-principal performers in musical theatre * ''Chorus'' (magazine), a Japanese manga magazine * ''Chorus'' (1974 film), a film directed by Mrinal Sen * ''The Chorus'' (1982 fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auroral Chorus
An auroral chorus is a series of electromagnetic waves at frequencies which resemble chirps, whistles, and quasi-musical sounds in predominantly rising tones when played as pressure waves (sound), which are created by geomagnetic storms also responsible for the auroras. The sounds last approximately 0.1 to 1.0 seconds. Other auroral sounds includes hissing, swishing, rustling and cracking. The electromagnetic waves are a type of natural radio waves, vibrations of electric and magnetic energy occurring at the same frequency as sound. Detection Auroral chorus can be detected primarily around the magnetic equator, specifically in two distinct frequency bands, one above the equatorial half gyro-frequency and one below it. The gyro-frequency ranges from 0.6 kHz to about 1.6 kHz. Distinguishable on high resolution wideband spectrographs, the wave amplitude grows linearly then switches to non-linear. Demonstrating a peak distribution near dawn, the auroral chorus is most dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Society Of Great Britain
The Radio Society of Great Britain (RSGB) is the United Kingdom's recognised national society for amateur radio operators. The society was founded in 1913 as the London Wireless Club, making it one of the oldest organisations of its kind in the world. Through its work, it represent the interests of the UK's 80,000 licensed radio amateurs in the United Kingdom and certain dependent territories of the United Kingdom at the International Amateur Radio Union, acting as a medium for communication between the licensed operators and the UK government. Role The RSGB has traditionally acted as the organisation through which its members interact with the telecommunications regulatory authority of the United Kingdom, Ofcom. Although Ofcom has used its web site to solicit opinions directly from all amateur radio enthusiasts and other interested parties, the RSGB continues to advise and to seek to influence Ofcom on the likely impact of proposed changes in many areas – from decisions on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Atmospheric
A radio atmospheric signal or sferic (sometimes also spelled "spheric") is a broadband electromagnetic impulse that occurs as a result of natural atmospheric lightning discharges. Sferics may propagate from their lightning source without major attenuation in the Earth–ionosphere waveguide, and can be received thousands of kilometres from their source. On a time-domain plot, a sferic may appear as a single high-amplitude spike in the time-domain data. On a spectrogram, a sferic appears as a vertical stripe (reflecting its broadband and impulsive nature) that may extend from a few kHz to several tens of kHz, depending on atmospheric conditions. Sferics received from about distance or greater have their frequencies slightly offset in time, producing ''tweeks''. When the electromagnetic energy from a sferic escapes the Earth-ionosphere waveguide and enters the magnetosphere, it becomes dispersed by the near-Earth plasma, forming a whistler signal. Because the source of the wh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pink Floyd
Pink Floyd are an English rock band formed in London in 1965. Gaining an early following as one of the first British psychedelic groups, they were distinguished by their extended compositions, sonic experimentation, philosophical lyrics and elaborate live shows. They became a leading band of the progressive rock genre, cited by some as the greatest progressive rock band of all time. Pink Floyd were founded in 1965 by Syd Barrett (guitar, lead vocals), Nick Mason (drums), Roger Waters (bass guitar, vocals), and Richard Wright (keyboards, vocals). Under Barrett's leadership, they released two charting singles and the successful debut album '' The Piper at the Gates of Dawn'' (1967). Guitarist and vocalist David Gilmour joined in December 1967; Barrett left in April 1968 due to deteriorating mental health. Waters became the primary lyricist and thematic leader, devising the concepts behind the band's peak success with the albums ''The Dark Side of the Moon'' (1973), ''W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cluster One
"Cluster One", an instrumental, is the opening track on Pink Floyd's 1994 album, ''The Division Bell''. History It is the first Pink Floyd song credited to just Wright/ Gilmour since " Mudmen", from the 1972 album ''Obscured by Clouds''. The piece has never been performed live by the band, although portions of it were included in the sound collage tape played before their 1994 concerts. Track overture The noise which opens the track caused some confusion among fans in 1994, who were unsure, on playing the album for the first time, whether or not their copy was faulty, as the noise lasts for just over 1 minute before any music begins. According to an interview with Andy Jackson, recording engineer for the album, this noise is electromagnetic noise from the solar wind. More precisely, this sound is a very low frequency record of dawn chorus and sferics, radio events respectively due to solar wind interference with Earth's magnetosphere, and lightning Lightning is a natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whistler (radio)
A whistler is a very low frequency (VLF) electromagnetic (radio) wave generated by lightning. Originally published by Stanford University Press, Stanford, California (1965). Frequencies of terrestrial whistlers are 1 kHz to 30 kHz, with a maximum amplitude usually at 3 kHz to 5 kHz. Although they are electromagnetic waves, they occur at audio frequencies, and can be converted to audio using a suitable receiver. They are produced by lightning strikes (mostly intracloud and return-path) where the impulse travels along the Earth's magnetic field lines from one hemisphere to the other. They undergo dispersion of several kHz due to the slower velocity of the lower frequencies through the plasma environments of the ionosphere and magnetosphere. Thus they are perceived as a descending tone which can last for a few seconds. The study of whistlers categorizes them into Pure Note, Diffuse, 2-Hop, and Echo Train types. Voyager 1 and 2 spacecraft detected whistler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hiss (electromagnetic)
Electromagnetic hiss is a naturally occurring Extremely Low Frequency/Very Low Frequency electromagnetic wave (i.e., 300 Hz – 10 kHz) that is generated in the plasma of either the Earth's ionosphere or magnetosphere. Its name is derived from its incoherent, structureless spectral properties which, when played through an audio system, sound like white noise (hence the onomatopoetic name, "hiss"). Varieties Hiss may be observed in any of several varieties depending on local time and L-shell of the observer: * ''Plasmaspheric hiss'' is generally observed within the plasmasphere, peaking in frequency slightly below ~1 kHz and rarely exceeding 3 kHz. * ''Exo-hiss'' and ''ELF hiss'' are two varieties of hiss observed outside of the plasmasphere, both having a spectrum similar to that of plasmaspheric hiss. * ''Midlatitude hiss'' is generally observed outside of the plasmasphere and tends to have frequencies between 2 and 10 kHz. * ''Auroral hiss'' is obser ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auroral Chorus
An auroral chorus is a series of electromagnetic waves at frequencies which resemble chirps, whistles, and quasi-musical sounds in predominantly rising tones when played as pressure waves (sound), which are created by geomagnetic storms also responsible for the auroras. The sounds last approximately 0.1 to 1.0 seconds. Other auroral sounds includes hissing, swishing, rustling and cracking. The electromagnetic waves are a type of natural radio waves, vibrations of electric and magnetic energy occurring at the same frequency as sound. Detection Auroral chorus can be detected primarily around the magnetic equator, specifically in two distinct frequency bands, one above the equatorial half gyro-frequency and one below it. The gyro-frequency ranges from 0.6 kHz to about 1.6 kHz. Distinguishable on high resolution wideband spectrographs, the wave amplitude grows linearly then switches to non-linear. Demonstrating a peak distribution near dawn, the auroral chorus is most dete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Electromagnetism
In physics, electromagnetism is an interaction that occurs between particles with electric charge. It is the second-strongest of the four fundamental interactions, after the strong force, and it is the dominant force in the interactions of atoms and molecules. Electromagnetism can be thought of as a combination of electricity and magnetism, two distinct but closely intertwined phenomena. In essence, electric forces occur between any two charged particles, causing an attraction between particles with opposite charges and repulsion between particles with the same charge, while magnetism is an interaction that occurs exclusively between ''moving'' charged particles. These two effects combine to create electromagnetic fields in the vicinity of charge particles, which can exert influence on other particles via the Lorentz force. At high energy, the weak force and electromagnetic force are unified as a single electroweak force. The electromagnetic force is responsible for m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auroral Light
An aurora (plural: auroras or aurorae), also commonly known as the polar lights, is a natural light display in Earth's sky, predominantly seen in high-latitude regions (around the Arctic and Antarctic). Auroras display dynamic patterns of brilliant lights that appear as curtains, rays, spirals, or dynamic flickers covering the entire sky. Auroras are the result of disturbances in the magnetosphere caused by the solar wind. Major disturbances result from enhancements in the speed of the solar wind from coronal holes and coronal mass ejections. These disturbances alter the trajectories of charged particles in the magnetospheric plasma. These particles, mainly electrons and protons, precipitate into the upper atmosphere (thermosphere/exosphere). The resulting ionization and excitation of atmospheric constituents emit light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomagnetic Storm
A geomagnetic storm, also known as a magnetic storm, is a temporary disturbance of the Earth's magnetosphere caused by a solar wind shock wave and/or cloud of magnetic field that interacts with the Earth's magnetic field. The disturbance that drives the magnetic storm may be a solar coronal mass ejection (CME) or (much less severely) a co-rotating interaction region (CIR), a high-speed stream of solar wind originating from a coronal hole. The frequency of geomagnetic storms increases and decreases with the sunspot cycle. During solar maximum, geomagnetic storms occur more often, with the majority driven by CMEs. The increase in the solar wind pressure initially compresses the magnetosphere. The solar wind's magnetic field interacts with the Earth's magnetic field and transfers an increased energy into the magnetosphere. Both interactions cause an increase in plasma movement through the magnetosphere (driven by increased electric fields inside the magnetosphere) and an increase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
