Galactic Concentration

galactic concentration

[gə′lak·tik ‚käns·ən′trā·shən]
A measure of the increasing density of stars toward the galactic plane, equal to the ratio of the density of stars of a given magnitude at the galactic plane to that at the galactic poles.
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 It might be outdated or ideologically biased.

Galactic Concentration


a property of the spatial distribution of stars in the Milky Way System manifested as an increase in the number of stars per unit area of sky as the Milky Way is approached. The degree of the galactic concentration of stars depends on their magnitude: the fainter the stars, the greater the galactic concentration. For stars with a stellar magnitude of 21, as an example, the galactic concentration is 16 times greater than for stars of the sixth stellar magnitude. The phenomenon of the Milky Way is a consequence of a galactic concentration mainly of faint stars. Galactic concentration is also observed in the distribution of interstellar gas and dust matter. Owing to galactic concentration, most of the galactic objects and the interstellar gas and dust matter occupy the space within the equatorial disk of the Milky Way System. Galactic concentration is also evident among thermal sources of galactic radio emission. The distribution of galactic objects is also characterized by a tendency to concentrate toward the center of the Milky Way System.


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