This just in from
Scientists Watch Baby Black Hole Get to Work Fast, a NASA feature story released Aug 18:
Baby black holes apparently come into the world kicking and screaming, not unlike humans. And they're fussy eaters, too. Scientists using NASA's Swift satellite say they have found newborn black holes, just seconds old, in a confused state of existence, sloppily gorging on material falling into them while somehow propelling other material away at great speeds.
There will be a paper appearing in the Sept 9 issue of the journal
Science.
SWIFT is a two year mission to study gamma ray bursts. It has three main instruments; an XRAY telescope, an ultraviolet and visible light telescope, and a "Burst Detector". The idea is that the burst detect identifies a gamma ray burst, and then swings the satellite around to bring the telescopes to bear. SWIFT has already been useful in bringing new data for astronomers. Here are some more extracts:
Quote:
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Originally Posted by NASA report on SWIFT
These black holes are born in massive star explosions. An initial blast obliterates the star. Yet the chaotic black hole activity appears to re-energize the explosion again and again over the course of several minutes. This is a dramatically different view of star death, one that entails multiple explosive outbursts and not just a single bang, as previously thought.
"Stars are exploding two, three and sometimes four times in the first minutes following the initial explosion," said Prof. David Burrows of Penn State, lead author on a paper appearing online today on Science Express and in the September 9 issue of Science. "First comes a blast of gamma rays followed by intense pulses of X-rays. The energies involved are much greater than anyone expected."
Scientists have seen this phenomenon in nearly half of the longer gamma-ray bursts detected by Swift so far. These gamma-ray bursts, the most powerful explosions known, are harbingers of a type of massive star explosion called a hypernova, bigger than a supernova. With the Swift satellite, scientists are finally able to see gamma-ray bursts within minutes after the trigger, instead of hours or days, and are now privy to newborn black hole activity.
Until this latest Swift discovery, scientists had assumed a simple scenario of a single explosion followed by a graceful afterglow of the dying embers. ...
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There is also a website where you can find out about the observations from day to day. SWIFT is picking up these massive explosions at the rate of one every couple of days; and other observatories also make occasional contributions. The web site is
http://grb.sonoma.edu/. There is a scrolling lists of bursts; click to get more detail of what was observed. This is an amazing site, able to bring cutting edge big project astronomy right into your computer screen as it happens.
Easy background information at
Gamma Ray Bursts: Introduction to a Mystery, at the NASA "Imagine the Universe" site. This is a NASA educational resource intended for kids, 14 and up. It's high quality, with lots of scope to press deeper. I frankly use it as a resource to help get a handle on the subject.
Cheers -- Sylas
24-August-2005, 12:41 PM
SWIFT sees new born black holes
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