From: Spudboy100@aol.com
Date: Fri Jul 12 2002 - 00:40:22 MDT
http://www.cnn.com/virtual/editions/europe/2000/roof/change.pop/frameset.exclud
e.html
July 11, 2002 Posted: 4:11 PM EDT (2011 GMT)
By Richard Stenger
CNN
(CNN) -- The universe could be much older than previously expected, based on
an examination of X-rays from a peculiar body near the edge of the known
cosmos, the European Space Agency said this week.
Many astronomers theorize that the universe began with the Big Bang between
13 billion and 14 billion years ago. In large part the estimate comes from
measuring the red shift of light and other energy from moving galaxies.
But scientists using ESA's XMM-Newton X-ray satellite observatory found that
a quasar about 13.5 billion light-years away offered a serious challenge to
the conventional age estimate.
"One distinct possibility to explain these observations is that at the red
shift we are looking at, the universe is older than we think," said Fred
Jansen, an XMM-Newton project scientist.
Red shifts resemble Doppler sound shifts. For example, sound waves from a
train whistle become longer and lower in pitch when a train moves away from
an observer.
Likewise, spectral light from galaxies seems to shift lower, observations
that astronomers use to estimate the speed and age of galaxies.
Moreover, spectral red shifts provide the scientific foundation for the
cosmological model that the universe continues to expand after the primordial
Big Bang.
"If you study the evolution the universe, one of the basic rules is that we
can tie red shift to age," Jansen said.
Yet the red shift of the quasar, a vibrant galaxy with a bright central
region and massive central black hole, revealed that it contained much more
iron than it should for its age.
Scientists think that exploding stars release iron and that the metal
gradually builds up in the universe. Earlier generation stars should have
little iron compared to later generation ones like the sun.
But iron in the quasar, known as APM 8279+5255, was three times more
plentiful than in our solar system, which puzzled astronomers.
"The solar system formed just 5 [billion] years ago, so it should contain
more iron than the quasar, which formed over 13.5 [billion] years ago," ESA
said in a statement.
By looking at distant objects, scientists in a sense look back in time. The
light from APM 8279+5255, for example, takes 13.5 billion years to reach
Earth, so we see it as looks 13.5 billion years ago.
Presumably, the quasar should look very young in the early cosmic snapshot,
but due to its iron-rich content, it looks much more mature.
The team, which includes researchers at the Max-Planck Institute in Germany,
said that the most likely explanation for the mystery is that the quasar and
hence the universe are older than expected.
They added that perhaps undiscovered "iron factories" are sprinkled through
the early universe, spitting out the metal through an unknown physical
process.
"This is the less likely solution in my opinion," Jansen said.
The report appeared in the July 10 issue of Astrophysical Journal Letters
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