A NEW study led by St
Andrews University scientists has found the universe has already
“guzzled its way” through about 20% of its original fuel reserves,
which have now turned into stars through matter produced by the “Big
Bang.”
The
statistics allied to the study are mind-numbing, and involve 10,000
giant galaxies, each comprising up to 10 billion stars, not to mention
phenomena such as bulges, discs and super-massive black holes. The
survey determined how much of the universe’s matter is locked in black
holes, some a million billion times more massive than Earth.
Project
leader Dr Simon Driver, of St Andrews, yesterday said the simplest
prognosis is the universe will be able to form stars for a further 70
billion years, then will start to go dark.
“However,
unlike our stewardship of the Earth, the universe is tightening its
belt, with the rate new stars are forming steadily decreasing,” he said.
Tracking
down what happened to normal matter dating back to the Big Bang 14
billion years ago has been a key goal for cosmologists for many years.
The survey reveals about 20% is locked up in stars, 0.1% lies in dust
expelled from the massive stars (and from which solid structures like
the Earth and man are made), and about 0.01% is in the form of
super-massive black holes.
“The
remaining 80% is almost completely in gaseous form lying within and
between galaxies and constitutes the reservoir from which future
generations of stars may form.”
The
survey involved scientists from Australia, Germany and the UK, and
resulted in the Millennium Galaxy Catalogue (MGC), the first to
catalogue reliable information on the bulge and disc components of so
many galaxies. On average half the stars in the universe lie in the
central bulges of galaxies, while the other half are found in discs
surrounding the bulges.
“By
measuring the stars in each galaxy’s bulge, we have also determined the
super-massive black hole mass at the heart of each galaxy,” said Dr
Alister Graham of the Australian National University. “It was then a
simple matter of summing these up to determine how much of the
universe’s matter is locked away in such huge black holes.”
The survey was presented at the general assembly of the International Astronomical Union in Prague.
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