The region of the atmosphere that lies in the upper mesosphere, extending from about 70 to 90 km (43 to 56 mi) above the Earth. The D region is responsible for the daytime absorption of high-frequency radio signals; at night, oxygen ions recombine with free electrons and form oxygen molecules that are transparent to such signals, which bounce off of the E region and back to Earth.
The region of the ionosphere that lies approximately 90 to 150 km (56 to 93 mi) above the Earth's surface. This region may affect long-distance communications because it influences radio waves in the 1-3 megahertz range.
The highest region of the ionosphere, consisting of free electrons generated by the ionizing effect of solar radiation. This region is subdivided into two layers, designated the F1 layer, and the F2 layer. The F1 layer extends from about 150 km (93 mi) to 240 km (149 mi) above the surface of the Earth and exists only during sunlight hours. At night it merges into the F2 layer. The F2 layer extends from about 240 km (149 mi) to 400 km (248 mi). The density of free electrons in this layer is much higher than it is in the F1 layer. It is the main reflecting layer for high frequency communications, both during sunlight hours and during the night.
A region of the Earth's upper atmosphere, extending from a height of 70 km (43 mi) to 400 km (248 mi) and containing atoms that have been ionized by radiation from the Sun. The ionosphere lies mostly in the lower thermosphere and is subdivided into three regions, the D region (70 km to 90 km; 43 to 56 mi), the E region (90 km to 150 km; 56 to 93 mi), and the F region (150 km to 400 km; 93 to 248 mi). The concentration of ionized atoms is lowest in the D region, intermediate in the E region, and highest in the F region. The ionosphere is useful for radio transmission because radio waves, which normally propagate in straight lines, are reflected off the ionized gas particles, thereby being transmitted long distances across the Earth's curved surface.
Find another word for ionosphere. In this page you can discover 19 synonyms, antonyms, idiomatic expressions, and related words for ionosphere, like: d region, e region, f region, d region e region f region, thermosphere, solar-wind, magnetosphere, magnetotail, boundary layer, magnetospheric and dayside.