Galaxies, galaxies everywhere - as far
as NASA's Hubble Space Telescope can see. This view of
nearly 10,000 galaxies is the deepest visible-light image
of the cosmos. Called the Hubble Ultra Deep Field, this
galaxy-studded view represents a "deep" core
sample of the universe, cutting across billions of light-years.
The snapshot includes galaxies of various
ages, sizes, shapes, and colors. The smallest, reddest
galaxies, about 100, may be among the most distant known,
existing when the universe was just 800 million years
old. The nearest galaxies - the larger, brighter, well-defined
spirals and ellipticals - thrived about 1 billion years
ago, when the cosmos was 13 billion years old.
In vibrant contrast to the rich harvest
of classic spiral and elliptical galaxies, there is a
zoo of oddball galaxies littering the field. Some look
like toothpicks; others like links on a bracelet. A few
appear to be interacting. These oddball galaxies chronicle
a period when the universe was younger and more chaotic.
Order and structure were just beginning to emerge.
The Ultra Deep Field observations, taken
by the Advanced Camera for Surveys, represent a narrow,
deep view of the cosmos. Peering into the Ultra Deep Field
is like looking through an eight-foot-long soda straw.
In ground-based photographs, the patch
of sky in which the galaxies reside (just one-tenth the
diameter of the full Moon) is largely empty. Located in
the constellation Fornax, the region is so empty that
only a handful of stars within the Milky Way galaxy can
be seen in the image.
In this image, blue and green correspond
to colors that can be seen by the human eye, such as hot,
young, blue stars and the glow of Sun-like stars in the
disks of galaxies. Red represents near-infrared light,
which is invisible to the human eye, such as the red glow
of dust-enshrouded galaxies.
The image required 800 exposures taken
over the course of 400 Hubble orbits around Earth. The
total amount of exposure time was 11.3 days, taken between
Sept. 24, 2003 and Jan. 16, 2004.
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