airglow

airglow

(air -gloh) (nightglow) The faint everpresent glow arising in the Earth's atmosphere that is light emitted (along with infrared radiation) during the recombination of ionized atoms and molecules following collisions with high-energy particles and radiation, mainly from the Sun. Airglow interferes with optical and infrared observations of faint celestial bodies.

Collins Dictionary of Astronomy © Market House Books Ltd, 2006

airglow

[′er‚glō]

(geophysics)

The quasi-steady radiant emission from the upper atmosphere over middle and low latitudes, as distinguished from the sporadic emission of auroras which occur over high latitudes. Also known as light-of-the-night-sky; night-sky light; night-sky luminescence; permanent aurora.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Airglow

 

the luminescence of gases found in the upper atmosphere at altitudes above 70–80 kilometers; an important component of the luminescence of the night sky.

Airglow exhibits not only a continuous spectrum but also atomic emission lines of oxygen, hydrogen, and sodium and molecular bands of the hydroxyl radical, oxygen, carbon dioxide, ozone, water, and nitrogen oxides. The emission of the individual components of airglow occurs at various altitudes in strata of varying thickness. The altitude and thickness of the layers may change. One of the main energy sources for airglow is the energy of solar radiation, which causes dissociation and ionization in the upper atmosphere; the subsequent recombination of particles produces airglow.

The intensity of all the emissions depends on the degree to which the upper atmosphere is illuminated, on the density, temperature, and composition of the upper atmosphere at the altitudes where the emissions occur, on solar and geomagnetic activity, and on the latitude of the observation site. There are daily and seasonal cycles.

The mechanisms responsible for airglow have not yet been fully explained. Observations of the spectra of airglow and of variations in its intensity dependent on heliogeophysical conditions are widely used to obtain data on the composition, density, temperature, and other properties of the atmosphere at high altitudes.

REFERENCE

Chamberlain, J. Fizika poliarnykh siianii i izlucheniia atmosfery. Moscow, 1963. (Translated from English.)

IU. L. TRUTTSE

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.