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NASA's Hubble Finds Most Distant Galaxy Candidate Ever Seen in Universe









WASHINGTON -- Astronomers have pushed NASA's Hubble Space Telescope to
its limits by finding what is likely to be the most distant object
ever seen in the universe. The object's light traveled 13.2 billion
years to reach Hubble, roughly 150 million years longer than the
previous record holder. The age of the universe is approximately 13.7 billion years.

The tiny, dim object is a compact galaxy of blue stars that existed
480 million years after the big bang. More than 100 such
mini-galaxies would be needed to make up our Milky Way. The new
research offers surprising evidence that the rate of star birth in
the early universe grew dramatically, increasing by about a factor of
10 from 480 million years to 650 million years after the big bang.

"NASA continues to reach for new heights, and this latest Hubble
discovery will deepen our understanding of the universe and benefit
generations to come," said NASA Administrator Charles Bolden, who was
the pilot of the space shuttle mission that carried Hubble to orbit.
"We could only dream when we launched Hubble more than 20 years ago
that it would have the ability to make these types of groundbreaking
discoveries and rewrite textbooks."

Astronomers don't know exactly when the first stars appeared in the
universe, but every step farther from Earth takes them deeper into
the early formative years when stars and galaxies began to emerge in
the aftermath of the big bang.

"These observations provide us with our best insights yet into the
earlier primeval objects that have yet to be found," said Rychard
Bouwens of the University of Leiden in the Netherlands. Bouwens and
Illingworth report the discovery in the Jan. 27 issue of the British
science journal Nature.

This observation was made with the Wide Field Camera 3 starting just a
few months after it was installed in the observatory in May 2009,
during the last NASA space shuttle servicing mission to Hubble. After
more than a year of detailed observations and analysis, the object
was positively identified in the camera's Hubble Ultra Deep
Field-Infrared data taken in the late summers of 2009 and 2010.

The object appears as a faint dot of starlight in the Hubble
exposures. It is too young and too small to have the familiar spiral
shape that is characteristic of galaxies in the local universe.
Although its individual stars can't be resolved by Hubble, the
evidence suggests this is a compact galaxy of hot stars formed more
than 100-to-200 million years earlier from gas trapped in a pocket of dark matter.

"We're peering into an era where big changes are afoot," said Garth
Illingworth of the University of California at Santa Cruz. "The rapid
rate at which the star birth is changing tells us if we go a little
further back in time we're going to see even more dramatic changes,
closer to when the first galaxies were just starting to form."

The proto-galaxy is only visible at the farthest infrared wavelengths
observable by Hubble. Observations of earlier times, when the first
stars and galaxies were forming, will require Hubble's successor, the
James Webb Space Telescope (JWST).

The hypothesized hierarchical growth of galaxies -- from stellar
clumps to majestic spirals and ellipticals -- didn't become evident
until the Hubble deep field exposures. The first 500 million years of
the universe's existence, from a z of 1000 to 10, is the missing
chapter in the hierarchical growth of galaxies. It's not clear how
the universe assembled structure out of a darkening, cooling fireball
of the big bang. As with a developing embryo, astronomers know there
must have been an early period of rapid changes that would set the
initial conditions to make the universe of galaxies what it is today.

"After 20 years of opening our eyes to the universe around us, Hubble
continues to awe and surprise astronomers," said Jon Morse, NASA's
Astrophysics Division director at the agency's headquarters in
Washington. "It now offers a tantalizing look at the very edge of the
known universe -- a frontier NASA strives to explore."

Hubble is a project of international cooperation between NASA and the
European Space Agency. NASA's Goddard Space Flight Center in
Greenbelt, Md., manages the telescope. The Space Telescope Science
Institute (STScI) conducts Hubble science operations. STScI is
operated for NASA by the Association of Universities for Research in
Astronomy, Inc., in Washington.

For more information about Hubble, visit:

http://www.nasa.gov/hubble

Source: NASA



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