Cosmos winks at
isle star watchers

New clues emerge from the
possible birth of a black hole

Scientists say they might know a little bit more about one of the most powerful and mysterious phenomena in the universe after spotting an infrared flash while observing a gamma-ray burst.

Identified by scientists at Los Alamos National Laboratory 30 years ago, gamma-ray bursts are believed to signal the births of black holes.

Still, little is known about the massive, short-lived explosions, including why they happen.

But scientists at a telescope at Mount Hopkins, Ariz., observing one gamma-ray burst, reported spotting something completely new on Dec. 19: an infrared flash. In the following days, the W.M. Keck Observatory atop Mauna Kea continued to keep watch as the energy of the blast faded.

The discovery of the flash is reported in today's issue of the journal Nature.

Gamma rays are a high- energy form of light, while infrared light are a relative lower-energy form of light. Neither is visible to the naked eye.

While infrared light has been seen following a burst before, it was believed to have been caused by interactions with material around the explosion site.

"This possibility of an infrared flash wasn't discussed much in gamma-ray burst theory," Joshua Bloom, astronomy professor at the University of California at Berkeley and senior author of the article, said in a statement. "It's like having a new look at an old friend. This flash in the infrared was very unexpected."

In their analysis of the event, the authors of the article concluded that the flash was the result of the process that creates the burst itself.

What attracts scientists to the gamma-ray burst is the prodigious amount of energy they put out within a tiny fraction of a second, said Frederic Chaffee, director of the Keck Observatory.

Each gamma-ray burst is more powerful than everything else in the universe combined. Within moments the blast is gone without a soul on the ground ever knowing it even happened -- except astronomers behind powerful telescopes.

The bursts are believed to be the result of the collision between neutron stars, super-dense, dead stars.

But astronomers are still in the early phases of understanding the physics of the phenomenon, and finding an application for those discoveries might not happen for decades, Chaffee said.

"We study phenomenon for the sake of understanding them," Chaffee said, "very much as we studied atoms at the early part of the 20th century when nobody could see an application. ... And yet atomic bombs came out of that and nuclear reactors."

Peters Automated Infrared Imaging Telescope
W.M. Keck Observatory

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