- (astronomy) A faint brightening of the night sky in the region of the ecliptic directly opposite the Sun.
- 1860, George Jones, “Recent Observations, by various persons, on the Gegenschein, or Completed Arch of the Zodiacal Light”, in Proceedings of the American Association for the Advancement of Science, Volume 13, Digitized edition, published 2007, page 172:
- My object in appearing before the Association, at this time, is to present the observations of several other persons on the gegenschein or completed arch of the zodiacal light, of which I have received accounts since our meeting in Motreal.
- 2001 Feb, John E. Bortle, “Introducing the Bortle Dark-sky Scale”, in Sky and Telescope, volume 101, number 2, page 126:
- The zodiacal light, gegenschein, and zodiacal band … are all visible.