Posted on 08/31/2006 12:01:15 AM PDT by neverdem
A star in a galaxy about 440 million light-years away released in a few seconds more energy than the sun will over the course of its entire lifetime, according to observations made on February 18. A high-energy jet of x-rays shot out from the doomed star's core and was captured by the Burst Alert Telescope on NASA's Swift satellite. The satellite relayed the information to astronomers on the ground, and within days a wide array of telescopes turned to the exploding object.
Meanwhile the other telescopes on Swift continued to observe the unusually long-lived burst; it lasted 40 minutes compared with other examples that flared up for only milliseconds. As the x-rays faded away, the star itself exploded in a spectacular supernova--shown in the before (l) and after (r) images above--the first such supernova to be observed from start to finish. Several teams of astronomers report their findings in a series of papers in today's Nature.
Beyond the novelty of the event, astronomers noted some unusual characteristics. Alicia Soderberg of the California Institute of Technology and her team used NASA's Chandra X-ray Observatory to determine that the initial beacon was an x-ray flash rather than a more typical kind of gamma-ray burst. Elena Pian of the Osservatorio Astronomico di Trieste in Italy and her team used the Very Large Telescope in Chile to link the burst and the subsequent supernova as well as to determine that this supernova was half as bright as those typically preceded by such a burst, despite its emanating from a star 20 times as massive as the sun. Such details led Paolo Mazzalli of the Max Planck Institute for Astrophysics in Garching, Germany, to speculate that the series of events might be driven by the birth of a magnetized neutron star, or magnetar.
Because such events are dimmer by nature than previously observed gamma-ray bursts, they are much harder to detect, and only the speedy work of Swift and the explosion's relative nearness allowed astronomers to study it. Nevertheless, such events are probably more common than their more powerful cousins, astronomers say. "Usually these events are not detected until after the supernova has brightened substantially," says Keith Mason of the Particle Physics and Astronomy Research Council in Swindon, England. "On this occasion, we were able to study the remarkable event in all its glory from the very beginning."
Image: SLOAN DIGITAL SKY SURVEY(L);NASA/SWIFT/ULTRAVIOLET OPTICAL TELESCOPE (R)
Supernova caught in its exploding act (NASA SWIFT detects milder gamma-ray burst GRB, X-ray flash)
interesting article (( ping ))
I take it there was no neutrino burst detected?
Did anybody catch a look at this star before it let out the burst? It would be interesting to know what went on on the weeks prior to the event.
Interesting. But other than the observation itself, which is neat, what's to be learned from this?
It is all Bush's fault.
How do you mean 'larger?'
Normally a photon from the galaxy arrives here so rarely that it isn't detected. The event released enough of a flood of photons that many were detected. That the photons were of particularly high energy allows us to determine what is going on.
In the usual meaning of 'larger,' the galaxy is on the order of a hundred LY across and the star, at its normal density, a small fraction of a LY.
Cosmology is not much more testable (or falsifiable) than evolution. You don't hear idiots challenging cosmology as you do fundamentalists yapping. But the preponderance of evidence is similar and this is another datum. Tagline...
Actually, I do encounter them. They're the young-earth, literal six-days of creation types, who insist that the whole universe is also young. If you haven't encountered them, you're fortunate.
In a few seconds, the star released more energy than our sun will have in its entire lifetime. And within days, a wide array of telescopes were looking at the aftermath. Kinda funny if you ask me. All of the action is over, and then everybody looks.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.