Near the same time that a mountain "exploded" and demolished a remote village in Leyte, Phillipines, astronomers were gaping at a stellar [and not seen since 1998] type of "explosion" in deep space.
Astronomers Agog Over Stellar Explosion
By Robert Naeyee
http://skyandtelescope.com/printable/news/article_1686.asp February 23, 2006
The astronomical community is abuzz with activity following the closest long-duration gamma-ray burst (GRB) observed since 1998. Major telescopes on the ground and in space are being trained on the source. Research astronomers have high hopes that further study of this event will provide crucial details about the connection of long GRBs extraordinarily powerful bursts of very-high-energy radiation that last several seconds to several minutes) to supernovae (the explosions of massive stars).
Advanced amateur astronomers will monitor the explosion's expanding fireball, which should brighten to about 16th magnitude over the next one to two weeks.
NASA's Swift satellite detected the GRB at 3:43:30 Universal Time on February 18th.
In less than 3 minutes Swift's Ultraviolet/Optical Telescope slewed to the correct coordinates, in the constellation Aries, and found the afterglow of the burst. Astronomers all over the world were alerted, and an armada of telescopes began to observe the fading afterglow.
At first the burst appeared rather strange because it lasted for about 30 minutes, which is 100 times longer than a typical long-duration GRB. Many astronomers wondered if it was instead a transient object within our Milky Way Galaxy. But follow-up observations from numerous ground-based telescopes quickly associated the afterglow with a small, 20th-magnitude star-forming galaxy about 470 million light-years from Earth.
Only a GRB could be so energetic to be seen by Swift at this distance. Even so, that's much closer thannearly all other GRBs.
"We've been waiting several years for a nearby GRB," says Dale Frail (National Radio Astronomy Observatory), who is observing the event at radio wavelengths with the Very Large Array in New Mexico.
The contemporaneous supernova confirms the prevailing theory for long-duration GRBs: that they occur when massive stars explode as supernovae and channel some of the energy into ejecta moving at nearly the speed of light.
From our 2/17/06 post:
'Mountain fell'
Lim said it was a sunny day when the people of Guinsaugon heard a loud crash and felt the earth shake before water mixed with mud and boulders fell from the mountain.
"It looked like the entire mountain fell on the village," said Mayor Mortera.
.... and as above, so below.
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