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E layer
E layern. A region of the ionosphere, extending from about 90 to 150 kilometers (55 to 95 miles) above the earth and influencing long-distance communications by strongly reflecting radio waves in the range from one to three megahertz. Also called E region, Heaviside layer, Kennelly-Heaviside layer.E layer n (General Physics) another name for E region E layer
n. the radio-reflective ionospheric layer of maximum electron density, at an altitude of about 60 mi. (100 km). [1930–35] Thesaurus| Noun | 1.E layer - a region of the ionosphere (from 50 to 90 miles up) that reflects radio waves of medium lengthE region, Heaviside layer, Kennelly-Heaviside layerionosphere - the outer region of the Earth's atmosphere; contains a high concentration of free electrons |
E layer
E layer[′ē ‚lā·ər] (geophysics) A layer of ionized air occurring at altitudes between 60 and 72 miles (100 and 120 kilometers) in the E region of the ionosphere, capable of bending radio waves back to earth. Also known as Heaviside layer; Kennelly-Heaviside layer. E layer A highly ionized part of the ionosphere with an ionization of around 105 free electrons/cm3. It is found at heights of 60 to 90 miles (100 to 150 km). Its height varies between summers and winters as well as days and nights. It is most pronounced in the daytime but does not entirely disappear at night. It reflects electromagnetic waves from 100 kHz to 20 MHz back to the earth. There is some evidence to indicate a second layer above the normal E layer, the E2 layer, which is located at about 90 miles (150 km). The E layer plays an important role in the quality of radio communications; radio waves bounce off the E layer. Also called the E1 layer, the Kennelly-Heaviside layer, and the Heaviside layer—the latter after its discoverer. See Heaviside layer.E layer
Synonyms for E layernoun a region of the ionosphere (from 50 to 90 miles up) that reflects radio waves of medium lengthSynonyms- E region
- Heaviside layer
- Kennelly-Heaviside layer
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