Hello Doves,

Here's an interesting article from the NY Times about a starburst that was recorded by scientists on Dec. 27, 2004, (day after the tsunami disaster)
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Starburst Was One of Brightest Objects Observed on Earth
By KENNETH CHANG

Published: February 18, 2005

For a fraction of a second in December, a dying remnant of an exploded star let
out of a burst of light that outshone the other half trillion stars in the Milky
Way galaxy combined.

Even on Earth, half a galaxy away, the starburst was one of the brightest
objects ever observed in the sky, after the Sun and perhaps a comet or two. The
magnitude of the event caught most astronomers by surprise.

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"Whoppingly bright," said Dr. Brian Gaensler, an astronomer at the
Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass. "It gave off
more energy in 0.2 seconds than the Sun does in 100,000 to 200,000 years."

Astronomers presented their observations today at a NASA news conference.
Scientific papers describing the event will be published in a coming issue of
the journal Nature.

No one on Earth directly saw the flare, because most of the light was gamma
rays, photons more energetic than X-rays. But instruments on many spacecraft,
including NASA's new Swift satellite, which was designed to measure gamma rays,
were overwhelmed by the sudden pulse on Dec. 27.

"It was really the big one," said Dr. Kevin Hurley, a researcher at the
University of California Berkeley's Space Sciences Laboratory. "You could not
have missed it."

Dr. Hurley and others pinpointed the source of the outburst, a neutron star
known as SGR 1806-20, about 50,000 light-years distant in the constellation
Sagittarius. Neutron stars are remnants of stars after they have exploded in
supernovae, and SGR 1806-20 is one of about 10 unusual neutron stars known as
magnetars that possess extraordinarily strong magnetic fields, about a trillion
times stronger than those around the Sun and more than a quadrillion times
stronger than the Earth's.

Two magnetar flares have been observed previously, one in 1979 and one in 1998.
The flares are believed to be generated when the magnetic fields shift, similar
to how the Sun releases solar flares. The Dec. 27 flare, however, was 100 times
more powerful.

One physicist, Dr. David Eicher of Ben-Gurion University in Israel, wrote a
paper in 2002 that suggested such magnetars might be capable of such big
explosions, but for most scientists, "We had no idea they could make a flare
this big," Dr. Gaensler said.

SGR 1806-20 has as much mass as 1.4 Suns, compressed into a ball about 15 miles
wide. It spins around once every 7.5 seconds, slow for a neutron star.
Discovered in 1979, SGR 1806-20 has at times emitted small gamma ray flares and
other times gone quiet. Its activity picked in the past last year.

"In retrospect, I guess you could say it was getting ready to let go," Dr.
Hurley said.

He said he thought that the magnetic fields, which are held in place by the
crust of the star, had become twisted, building stress. "At some point, it gives
way like an earthquake," he said.

In the aftermath of the flare, Dr. Gaensler and his colleagues used radio
telescopes on Earth to track a shock wave radiating outward from SGR 1806-20 at
a third of the speed of light. "Which is not what you tend to see in the galaxy
every day," he said.

The star itself continues to spin as before, one revolution every 7.5 seconds.
"Amazingly, the neutron star is still there," Dr. Gaensler said. "It did not
explode or blow itself apart to bits." <Clip Copyright New York Times

PK