PASADENA,
Calif. (Reuters) - A galaxy near the Big Dipper constellation
that was once believed to be the ``Most Distant Object Known''
is closer than originally thought, scientists said Thursday.
The faint
galaxy, informally known as ``Sharon,'' was first seen last year
in images captured by NASA (news - web sites)'s Hubble Space Telescope,
astronomers at NASA's Jet Propulsion Laboratory (JPL) said. Their
research is presented in the latest issue of the British science
magazine ``Nature.''
At that time
scientists inferred a distance of approximately 12.5 billion light
years, which would make ``Sharon'' the most distant object known.
JPL scientists said the distance was equivalent to looking back
in time to about 600 million years after the Big Bang or just
five percent of the current age of the universe.
However, new
observations show the galaxy is closer than previously believed,
likely about 10 billion light years away, corresponding to 3.3
billion years after the Big Bang or about 25 percent of the current
age of the universe.
JPL scientists
based their findings on a revamped analysis of the galaxy's ``redshift,''
or speed at which it is moving away from the earth as the universe
expands, JPL spokeswoman Jane Platt said.
The faster
an object moves away, the more its light shifts to the red part
of the spectrum (indicating longer wavelengths). In the 1920s,
astronomer Edwin Hubble discovered that the faster an object appears
to move, the farther away it is.
``The identification
of galaxies at extreme distances provides our most direct information
on the earliest phases of galaxy formation,'' said Daniel Stern,
whose team made the new observations using images obtained at
the W.M. Keck Observatory, Mauna Kea, Hawaii.
With this
galaxy's distance debunked, the new titleholder for most distant
object in the universe is a remote galaxy or quasar, identified
by astronomers in September 2000.
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