spacetoday.net: Hubble and Keck jointly discover most distant galaxy

Posted: Mon, Feb 16, 2004, 8:30 PM ET (0130 GMT)
Abell 2218 galaxy cluster (STScI)

Astronomers using the Hubble Space Telescope and the Keck Observatory announced Sunday that they have discovered the most distant galaxy in the known universe, dating back to when the universe was less than a billion years old. Astronomers initially detected the object in images from Hubble of the region around the nearby galaxy cluster Abell 2218. The galaxy cluster acts as a gravitational lens, permitting astronomers to observe distant, faint objects. Followup observations by the 10-meter telescopes of the Keck Observatory determined the object had a redshift of approximately 7, corresponding to a distance from Earth of about 13 billion light-years. Astronomers said the light being observed from the object originated when the universe was only 750 million years old, around the time the first galaxies formed at the end of a "Dark Ages" after the Big Bang. The object is thought to be relatively small for a galaxy — only 2,000 light-years across — but very active in terms of star formation.