Search results
Results from the WOW.Com Content Network
EPSG Geodetic Parameter Dataset (also EPSG registry) is a public registry of geodetic datums, spatial reference systems, Earth ellipsoids, coordinate transformations and related units of measurement, originated by a member of the European Petroleum Survey Group (EPSG) in 1985.
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 ...
Frequency Band Terra: 8212.5 MHz: 8175-8215 MHz METEOROLOGICAL-SATELLITE SERVICE Earth exploration-satellite service Aqua: 8160 MHz: 8025-8175 MHz: Earth exploration-satellite service NOAA 17,18 1707 MHz 1700-1710 MHz: Meteorological-satellite service: ERS-2 (High rate) 8140 MHz 8025-8175 MHz: Earth exploration-satellite service SPOT 4,5 8253 MHz
A telluric current (from Latin tellūs 'earth'), or Earth current, [1] is an electric current that flows underground or through the sea, resulting from natural and human-induced causes. These currents have extremely low frequency and traverse large areas near or at Earth 's surface.
Ground conductivity is an extremely important factor in determining the field strength and propagation of surface wave (ground wave) radio transmissions. Low frequency (30–300 kHz) and medium frequency (300–3000 kHz) radio transmissions are particularly reliant on good ground conductivity as their primary propagation is by surface wave. [1]
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 official planetary K p-index is derived by calculating a weighted average of K-indices from a network of 13 geomagnetic observatories at mid-latitude locations.Since these observatories do not report their data in real-time, various operations centers around the globe estimate the index based on data available from their local network of observatories.
You are free: to share – to copy, distribute and transmit the work; to remix – to adapt the work; Under the following conditions: attribution – You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses ...