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The Schumann resonances are a set of spectrum peaks in the extremely low frequency (ELF) portion of the Earth's electromagnetic field spectrum. Schumann resonance is due to the space between the surface of the Earth and the conductive ionosphere acting as a waveguide. The limited dimensions of the earth cause this waveguide to act as a resonant ...
The global electromagnetic resonance phenomenon is named after physicist Winfried Otto Schumann who predicted it mathematically in 1952. Schumann resonances are the principal background in the part of the electromagnetic spectrum [2] from 3 Hz through 60 Hz [3] and appear as distinct peaks at extremely low frequencies around 7.83 Hz (fundamental), 14.3, 20.8, 27.3, and 33.8 Hz.
The fundamental Schumann resonance is at approximately 7.83 Hz, the frequency at which the wavelength equals the circumference of the Earth, and higher harmonics occur at 14.1, 20.3, 26.4, and 32.4 Hz, etc. Lightning strikes excite these resonances, causing the Earth–ionosphere cavity to "ring" like a bell, resulting in a peak in the noise ...
A frequency vs. time plot (spectrogram) showing several whistler signals amidst a background of sferics as received at Palmer Station, Antarctica on August 24, 2005.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.
Use of NASA logos, insignia and emblems is restricted per U.S. law 14 CFR 1221.; The NASA website hosts a large number of images from the Soviet/Russian space agency, and other non-American space agencies.
Ecological light pollution [1] is the effect of artificial light on individual organisms and on the structure of ecosystems as a whole.. The effect that artificial light has upon organisms is highly variable, [2] and ranges from beneficial (e.g. increased ability for predator species to observe prey) to immediately fatal (e.g. moths that are attracted to incandescent lanterns and are killed by ...
Light pollution is the presence of any unwanted, inappropriate, or excessive artificial lighting. [1] [2] In a descriptive sense, the term light pollution refers to the effects of any poorly implemented lighting sources, during the day or night. Light pollution can be understood not only as a phenomenon resulting from a specific source or kind ...
Globe at Night is an international scientific research program that crowdsources measurements of light pollution in the night sky. At set time periods within each year, the project asks people to count the number of stars that they can see from their location and report it to the project's website.