'Dropouts' pinpoint earliest galaxies

		IMAGE: This is a composite of false color images of the galaxies found at the early epoch around 800 million years after the Big Bang. The upper left panel presents the... Click here for more information.

Pasadena, CA—Astronomers, conducting the broadest survey to date of galaxies from about 800 million years after the Big Bang, have found 22 early galaxies and confirmed the age of one by its characteristic hydrogen signature at 787 million years post Big Bang. The finding is the first age-confirmation of a so-called dropout galaxy at that distant time and pinpoints when an era called the reionization epoch likely began. The research will be published in a December issue of the Astrophysical Journal.