Ionosphere

The region of the earth's upper atmosphere containing a small percentage of free electrons and ions produced by photoioniza- tion of the constituents of the atmosphere by solar ultraviolet radiation at very short wavelengths (

ionosphere

A region of charged particles in a planet's upper atmosphere; the part of the earth's atmosphere beginning at an altitude of about 400 kilometers (25 miles) and extending outward 400 kilometers (250 miles) or more.
Found on http://www.solarviews.com/eng/terms.htm

Ionosphere

The region of the Earth's upper atmosphere containing a small percentage of free electrons and ions produced by photoionization of the constituents of the atmosphere by solar ultraviolet radiation. The ionosphere significantly influences radiowave propagation of frequencies less than about 30 MHz.
Found on http://hesperia.gsfc.nasa.gov/sftheory/glossary.htm

Ionosphere

Rarefied, ionized region of the Earth's atmosphere, between approximately 60 and 400 km.
Found on http://www.encyclo.co.uk/local/20130

Ionosphere

A region of the upper atmosphere that reflects some radio waves.
Found on http://www.bbc.co.uk/weather/weatherwise/glossary/i.shtml

ionosphere

[n] - the outer region of the Earth`s atmosphere
Found on http://www.webdictionary.co.uk/definition.php?query=ionosphere

Ionosphere

The region of the Earth's upper atmosphere containing a small percentageof free electrons and ions produced by photo ionization of the constituentsof the atmosphere by solar ultraviolet radiation at very short wavelengths(less than 1000 angstroms). The ionosphere significantly influences radio wavepropagation of frequencies less than about 30 MHz. ...
Found on http://www.diracdelta.co.uk/science/source/i/o/ionosphere/source.html

ionosphere

the upper layer of the air where some of the gas molecules have been ionized by high energy radiation or atomic particles from the Sun. Older forms of radio communication depended on its presence for transmission beyond the horizon.
Found on http://www.encyclo.co.uk/local/20842

ionosphere

<radiobiology> Ionised region of the upper earth atmosphere, which behaves like a plasma, including reflection of AM radio waves and generation of auroral glows. ... (09 Oct 1997) ...
Found on http://www.encyclo.co.uk/local/20973

ionosphere

noun the outer region of the Earth`s atmosphere; contains a high concentration of free electrons
Found on http://wordnetweb.princeton.edu/perl/webwn?s=ionosphere

ionosphere

(from the article `ionosphere and magnetosphere`) IonosphereThe portion of the thermosphere where charged particles (ions) are abundant is called the ionosphere. These ions result from the removal of electrons ... ...through the overlying layer known as the thermosphere. Also above about 80–90 km there is an increasing fraction of ...
Found on http://www.britannica.com/eb/a-z/i/37

Ionosphere

A region in the atmosphere above 50 kilometers from the surface where relatively large concentrations of ions and free electrons exist. The ionosphere is important for human communications because it re-directs AM radio transmissions. This process extends the distance that radio transmissions can travel.
Found on http://www.physicalgeography.net/physgeoglos/i.html

IONOSPHERE

A complex atmospheric zone of ionized gases that extends between 50 and 400 miles (80 to 640 kilometers) above the earth's surface. It is located between the mesosphere and the exosphere and is included as part of the thermosphere.
Found on http://www.weather.com/glossary/i.html

ionosphere

that part of the upper atmosphere characterized by the presence of ions and free electrons mainly arising from photo-ionization, the electron density being sufficient to produce significant modification of the propagation of radio waves in certain frequency bands NOTE - The Earth's ionosphere extends approximately from a height of 50 km to a height...
Found on http://www.electropedia.org/iev/iev.nsf/display?openform&ievref=705-06-11

ionosphere

The part of the atmosphere that is kept partially (up to 0.1%) ionized by ultraviolet light and X-rays from the Sun. It lies immediately above the stratosphere, roughly between altitudes 50 and 500 km, and is divided into three main layers, D, E, and F, on the basis of radio wave propagation propert...
Found on http://www.daviddarling.info/encyclopedia/I/ionosphere.html

ionosphere

ionosphere (īon'usfēr) , series of concentric ionized layers forming part of the upper atmosphere of the earth from around 30 to 50 mi (50 to 80 km) to 250 to 370 mi (400 to 600 km) where it merges with the magnetosphere, the region of the Van Allen radiation belts. The degree of ion...
Found on http://www.infoplease.com/ce6/sci/A0825414.html

Ionosphere

The ionosphere is the ionised layer of the earth's atmosphere. It extends over altitudes from about 50 km to about 600 km.
Found on http://www.probertencyclopaedia.com/browse/GI.HTM

ionosphere

Ionized layer of Earth's outer atmosphere (60–1,000 km/38–620 mi) that contains sufficient free electrons to modify the way in which radio waves are propagated, for instance by reflecting them back to Earth. The ionosphere is thought to be produced by absorption of the Sun's ultraviolet radiation. The British Antarctic Survey ...
Found on http://www.talktalk.co.uk/reference/encyclopaedia/hutchinson/m0006405.html

Ionosphere

A region of charged particles in a planet's upper atmosphere. In Earth's atmosphere, the ionosphere begins at an altitude of about 25 miles and extends outward about 250.
Found on http://www.seasky.org/astronomy/astronomy-glossary.html

Ionosphere

An atmospheric layer dominated by charged, or ionized, atoms that extend from about 38 to 400 miles above the Earth's surface.
Found on http://www.braeunig.us/space/glossary.htm

Ionosphere

Also known as the thermosphere. A layer in the atmosphere above the mesosphere extending from about 80km above the Earth's surface. It can be considered a distinct layer due to a rise in air temperature with increasing height. Atmospheric densities here are very low.
Found on http://www.encyclo.co.uk/local/22268

Ionosphere

A complex atmospheric zone of ionized gases that extends between 50 and 400 miles (80 to 640 kilomet
Found on http://www.superglossary.com/Glossary/Science/Weather/

Ionosphere

A region of the Earth's atmosphere.
Found on http://www.kidsastronomy.com/dictionary.htm

Ionosphere

An atmospheric layer with a high concentration of ions and free electrons.
Found on http://planetfacts.org/space-terms/

Ionosphere

A layer of atmosphere composed largely of ions, that reflects radio waves.
Found on http://jot101.com/2015/05/a-z-of-science-fiction-words/
No exact match found