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Poster Version
A massive cluster of yellowish galaxies is seemingly caught in a spider
web of eerily distorted background galaxies in the left-hand image, taken
with the Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space
Telescope.
The gravity of the cluster's trillion stars acts as a cosmic "zoom lens,"
bending and magnifying the light of the galaxies located far behind it, a
technique called gravitational lensing. The faraway galaxies appear in the
Hubble image as arc-shaped objects around the cluster, named Abell 1689.
The increased magnification allows astronomers to study remote galaxies
in greater detail.
One galaxy is so far away, however, it does not show up in the
visible-light image taken with ACS [top, right], because its light is
stretched to invisible infrared wavelengths by the universe's expansion.
Astronomers used Hubble's Near Infrared Camera and Multi-Object
Spectrometer (NICMOS) and NASA's Spitzer Space Telescope with its
Infrared Array Camera (IRAC)—with help from the gravitational
lensing cluster—to see the faraway galaxy.
The distant galaxy, dubbed A1689-zD1, appears as a grayish-white smudge in
the close-up view taken with Hubble's NICMOS [center, right], and as a
whitish blob in the Spitzer IRAC close-up view [bottom, right]. The galaxy
is brimming with star birth. Hubble and Spitzer worked together to show
that it is one of the youngest galaxies ever discovered. Astronomers
estimate that the galaxy is 12.8 billion light-years away. Abell 1689 is
2.2 billion light-years away.
A1689-zD1 was born during the middle of the "dark ages," a period in the
early universe when the first stars and galaxies were just beginning to
burst to life. The dark ages lasted from about 400,000 to roughly a
billion years after the Big Bang. Astronomers think that A1689-zD1 was one
of the galaxies that helped end the dark ages.
The ACS images were taken in 2002, the NICMOS images in 2005 and 2007, and
the Spitzer IRAC images in 2006.
The Hubble Space Telescope is a project of international cooperation
between NASA and the European Space Agency. The Space Telescope Science
Institute conducts Hubble science operations. The institute is operated
for NASA by the Association of Universities for Research in Astronomy,
Inc., Washington, D.C.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages the Spitzer
Space Telescope mission for NASA's Science Mission Directorate,
Washington. Science operations are conducted at the Spitzer Science Center
at the California Institute of Technology, also in Pasadena. Caltech
manages JPL for NASA.
