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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.
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.
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 ...
The images are corrected for nearly constant geometric resolution prior to being broadcast; as such, the images are free of distortion caused by the curvature of the Earth. Of the two images, one is typically long-wave infrared (10.8 micrometers ) with the second switching between near-visible (0.86 micrometers) and mid-wave infrared (3.75 ...
For the real Earth's surface, the ground wave becomes dissipated and depends on the orography along the ray path. [5] For VLF waves at shorter distances, this effect is, however, of minor importance, and the reflection factor of the Earth is R e = 1 {\displaystyle R_{e}=1} , in a first approximation.
EarthTV's camera in Macau. EarthTV Network GmbH is a German satellite Television Network, which airs live broadcasts from its camera network around the world. [1] [2] Cameras are located in well-known cities as well as lesser-known locations. EarthTV cameras usually feature beaches, mountains, seaside resorts, or skylines of major cities.
Daily (or Earth's rotation frequency) 10 −4: 100 μHz ~277.8 μHz: Hourly 10 −2: 1 centihertz (cHz) ~16.667 mHz: One rpm: 10 −1: 1 decihertz (dHz) 189 mHz: Acoustic – frequency of G −7, the lowest note sung by the singer with the deepest voice in the world, Tim Storms. His vocal cords vibrate 1 time every 5.29 seconds. 10 0: 1 hertz ...
For wave trains with a very small difference in frequency (and thus wavenumbers), this pattern of wave groups may have the same velocity as seismic waves, between 1500 and 3000 m/s, and will excite acoustic-seismic modes that radiate away. Wave groups generated by waves with opposing directions. The blue curve is the sum of the red and black.