From: Walter Watts (wlwatts@home.com)
Date: Wed Jan 09 2002 - 11:59:18 MST
New Theory on Big Bang
01/09/2002 3:40 AM EST
By PAUL RECER
WASHINGTON (AP) - An outburst of star formation ended a half billion
years of utter darkness following the Big Bang, the theoretical start of
the universe, according to a study that challenges old ideas about the
birth of the first stars.
An analysis of very faint galaxies in the deepest view of the universe
ever captured by a telescope suggests there was an eruption of stars
that burst to life and pierced the blackness very early in the 15
billion-year history of the universe.
The study, by Kenneth M. Lanzetta of the State University of New York at
Stony Brook, challenges the long held belief that star formation started
slowly after the Big Bang and didn't peak until some 5 billion years
later.
"Star formation took place early and very rapidly," Lanzetta said
Tuesday at a National Aeronautics and Space Administration news
conference. "Star formation was 10 times higher in the distant early
universe than it is today."
Lanzetta's conclusions are based on an analysis of what is called a deep
field study by the Hubble Space Telescope. To capture the faintest and
most distant images possible, the Hubble focused on an ordinary bit of
sky for more than 14 days, taking a picture of eve ry object within a
small, deep slice of the heavens. The resulting images are faint, fuzzy
bits of light from galaxies near and far, including some more than 14
billion light-years away, said Lanzetta.
The surprise was that the farther back the telescope looked, the greater
the star-forming activity was.
"Star formation continued to increase to the very earliest point that we
could see," said Lanzetta. "We are seeing close to the first burst of
star formation."
Bruce Margon of the Space Telescope Science Institute in Baltimore said
Lanzetta's conclusions are a "surprising result" that will need to be
confirmed by other studies.
"This suggests that the great burst of star formation was at the
beginning of the universe," said Margon, noting that, in effect: "The
finale came first."
"If this can be verified, it will dramatically change our understanding
of the universe," said Anne Kinney, director of the astronomy and
physics division at NASA.
In his study, Lanzetta examined light captured in the Hubble deep field
images, using up to 12 different light filters to separate the colors.
The intensity of red was used to establish the distance to each point of
light. The distances were then used to create a three-dimensional
perspective of the 5,000 galaxies in the Hubble picture.
Lanzetta also used images of nearby star fields as a yardstick for
stellar density and intensity to conclude that about 90 percent of the
light in the very early universe was not detected by the Hubble. When
this missing light was factored into the three-dimensional perspective,
it showed that the peak of star formation came just 500 million years
after the Big Bang and has been declining since.
Current star formation, he said, "is just a trickle" of that early burst
of stellar birth.
Lisa Storrie-Lombardi, a California Institute of Technology astronomer,
said that the colors of the galaxies in the Hubble deep field images
"are a very good indication of their distance."
Current theory suggests that about 15 billion years ago, an infinitely
dense single point exploded - the Big Bang - creating space, time,
matter and extreme heat. As the universe cooled, light elements, such as
hydrogen and helium, formed. Later, some areas became more dense with
elements than others, forming gravitational centers that attracted more
and more matter. Eventually, celestial bodies became dense enough to
start nuclear fires, setting the heavens aglow. These were newborn
stars.
Storrie-Lombardi said that current instruments and space telescopes now
being planned could eventually, perhaps, see into the Dark Era, the time
before there were stars.
"We are getting close to the epoch where we can not see at all," she
said.
--- On the Net: Hubble images: http://oposite.stsci.edu/pubinfo/pr/2002/02 Also: http://hubble.stsci.edu/go/news -- Walter Watts Tulsa Network Solutions, Inc.
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