D2 radio source

D2 radio source

[¦dē¦tü ′rād·ē·ō ‚sȯrs]
(astronomy)
A radio source consisting of a small, variable nuclear component sometimes coincident with an optical object, and a second, larger component with a much steeper radio spectrum.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.