What did the first galaxies look like? To help answer this
question, the Hubble Space Telescope has just finished taking
the eXtreme Deep Field (XDF), the deepest image of the universe
ever taken in Pictured above, the XDF shows a sampling of some
of the oldest galaxies ever seen, galaxies that formed just
after the dark ages, 13 billion years ago, when the universe was
only a few percent of its present age. The Hubble Space
Telescope's ACS camera and the infrared channel of the WFPC3
camera took Combining efforts spread over 10 years, the XDF is
more sensitive, in some colors, than the original Hubble Deep
Field (HDF), the Hubble Ultra Deep Field (HUDF) completed in
2004, and the HUDF Infrared completed in 2009. Astronomers the
world over will likely study the XDF for years to come to better
understand how stars and galaxies formed in the early universe.
D. Magee, and P. Oesch (UCSC), R. Bouwens (Leiden Obs.), and the