Mutual UFO Network - MUFONET-BBS Network
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                   ASTRONOOMY NEWS - WIRE
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=START=   XMT: 11:11 Mon Jan 14  EXP: 11:00 Thu Jan 17

U.S. ASTRONOMERS REPORT EXPLOSIVE QUASAR ERUPTION SEEN
(JAN. 14) UPI - Astronomers Monday announced the discovery of
a record eruption from a quasar 2 billion light years away, an
unimaginable three-minute burst of energy that, when viewed
from Earth, rivaled the total output of the sun over nearly 1
million years.

''Quasars, even in their quiet state, are really mind boggling
in how much energy they radiate,'' said astronomer Ronald
Remillard, co-author of a paper on the flare presented Monday
at a meeting of the American Astronomical Society in
Philadelphia.

''That's just part of why so many astronomy researchers are
working on trying to really nail down the last secrets about
them because it's just phenomenal what they do.''
A Japanese satellite named ''Ginga'' - Galaxy - recorded the
X-ray burst from quasar PKS 0558-504 in the constellation
Orion at 8:12 p.m.  EST Nov. 13, 1989.  The quasar is believed
to be 2 billion light years from Earth, so far that light,
traveling 186,000 miles per second, took 2 billion years to
cover the distance.

The announcement of the flare discovery was made Monday after
extensive analysis to make sure the unusual signal was real.
The discovery was made by graduate student Bruce Grossan,
Remillard and Hale Bradt, all of the Massachusetts Institute
of Technology in Cambridge, Mass.; Takaya Ohashi of the
University of Tokyo; and Yasuo Tanaka, Kiyoshi Hayashida and
Fumijoshi Makino, all of the Institute of Space and
Astronautical Science in Sagamihara, Japan.

Remillard said the signal detected by Ginga indicated a record
three-minute eruption equal to the sun's total energy output
over nearly 1 million years, assuming the outburst was spread
evenly in all directions.

To put that into perspective, the sun produces about 53
million watts of power each second for every square yard of
its surface, enough power per square yard to light 100,000
average homes.

Put another way, the sun converts 660 million tons of matter
into energy every second. The conversion of a mere 1 pound of
hydrogen into energy through nuclear fusion can power a 100
watt light bulb for 450, 000 years.

But when it comes to sheer energy production, nothing in the
known universe rivals the output of quasars, mysterious
objects that can be as small as a single solar system and yet
outshine entire galaxies.

It is widely believed that quasars are located at the cores of
distant galaxies that serve as hosts to super-massive black
holes, objects with such tremendous gravity that not even
light can escape. Quasar PKS 0558-504 is thought to have a
central black hole with a mass of at least 100 million times
that of the sun.

As gas, dust and other stellar debris falls into such black
holes, it is heated to extreme temperatures. High energy light
in the form of X-rays and gamma rays is emitted before the
matter falls into the black hole, past the point where gravity
prevents anything from escaping.

''For the time being, it's certainly taken for granted that
the gravity of a super-collapsed object is about the only
thing anyone can imagine that could power (a quasar),''
Remillard said in a telephone interview from Cambridge.
But the very energy emitted by material falling into the hole
can produce an outward pressure pushing against the falling
matter.

''The natural thing to assume if you see a quasar flare is
that, well, just an extra blob of stuff fell into the
system,'' Remillard said.  ''The problem is ... while gravity
is pulling things in and keeping the gas together near the
quasar, as you start adding more and more light coming out of
the thing, the light starts pushing on the gas. It wants to
drive stuff outward.''

Calculations show there is a limit to how much a quasar's
energy output can increase in a given period of time ''before
you're actually getting too much light out of the system and
it's going to stop the gas from going in,'' Remillard said.
''The problem with our flare is we exceed that number.''
But by assuming the flare was caused by matter traveling in
the direction of Earth at a velocity near the speed of light,
the astronomers were able to use the concept of ''relativistic
beaming'' to explain the titanic eruption, based on Einstein's
theory of relativity.

''This condition ... may arise if part of the energy of the
infalling matter is directed to the formation of a jet of gas
that escapes in a narrow beam (like a high-pressure hose)
before falling too near to the black hole,'' the researchers
said in a news release.

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 * Origin: MUFONET-BBS Network - Memphis, Tenn 901-785-4943 (1:123/26)