The explosion of a star halfway across the universe was so huge it set a record for the most distant object that could be seen on Earth by the naked eye.
A star 7.5 billion light years away exploded, giving off the brightest gamma-ray burst afterglow ever seen.
The aging star, in a previously unknown galaxy, exploded in a gamma ray burst 7.5 billion light years away, its light finally reaching Earth early Wednesday.
The gamma rays were detected by NASA's Swift satellite at 2:12 a.m. "We'd never seen one before so bright and at such a distance," NASA's Neil Gehrels said.
It was bright enough to be seen with the naked eye.
However, NASA has no reports that any skywatchers spotted the burst, which lasted less than an hour.
Telescopic measurements show that the burst -- which occurred when the universe was about half its current age -- was bright enough to be seen without a telescope.
"Someone would have had to run out and look at it with a naked eye, but didn't," said Gehrels, chief of NASA's astroparticles physics lab at Goddard Space Flight Center in Greenbelt, Md.
The starburst would have appeared as bright as some of the stars in the handle of the Little Dipper constellation, said Penn State University astronomer David Burrows. How it looked wasn't remarkable, but the distance traveled was.
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The 7.5 billion light years away far eclipses the previous naked eye record of 2.5 million light years. One light year is 5.9 trillion miles.
"This is roughly halfway to the edge of the universe," Burrows said.
Before it exploded, the star was about 40 times bigger than our sun. The explosion vaporized any planet nearby, Gehrels said.
From Wikipedia:
Research has been conducted to investigate the consequences of Earth being hit by a beam of gamma rays from a nearby (about 500 light years) gamma ray burst. This is motivated by the efforts to explain mass extinctions on Earth and estimate the probability of extraterrestrial life. A gamma ray burst at 6000 light years would result in mass extinction; a 1000 light year distant burst would be equivalent to a 100,000 megaton nuclear explosion. A burst 100 light years away would blow away the atmosphere, create tidal waves, and start to melt the surface of the earth. There is a one in a million chance that there could be a gamma ray burst as near as the earth's closest star, Alpha Centauri, in the lifetime of the earth. Such a burst, at 4.3 light years distant, would effectively incinerate the earth.
A star 7.5 billion light years away exploded, giving off the brightest gamma-ray burst afterglow ever seen.
The aging star, in a previously unknown galaxy, exploded in a gamma ray burst 7.5 billion light years away, its light finally reaching Earth early Wednesday.
The gamma rays were detected by NASA's Swift satellite at 2:12 a.m. "We'd never seen one before so bright and at such a distance," NASA's Neil Gehrels said.
It was bright enough to be seen with the naked eye.
However, NASA has no reports that any skywatchers spotted the burst, which lasted less than an hour.
Telescopic measurements show that the burst -- which occurred when the universe was about half its current age -- was bright enough to be seen without a telescope.
"Someone would have had to run out and look at it with a naked eye, but didn't," said Gehrels, chief of NASA's astroparticles physics lab at Goddard Space Flight Center in Greenbelt, Md.
The starburst would have appeared as bright as some of the stars in the handle of the Little Dipper constellation, said Penn State University astronomer David Burrows. How it looked wasn't remarkable, but the distance traveled was.
Don't Miss
http://www.cnn.com/2008/TECH/s...ing.star.ap/index.html
The 7.5 billion light years away far eclipses the previous naked eye record of 2.5 million light years. One light year is 5.9 trillion miles.
"This is roughly halfway to the edge of the universe," Burrows said.
Before it exploded, the star was about 40 times bigger than our sun. The explosion vaporized any planet nearby, Gehrels said.
From Wikipedia:
Research has been conducted to investigate the consequences of Earth being hit by a beam of gamma rays from a nearby (about 500 light years) gamma ray burst. This is motivated by the efforts to explain mass extinctions on Earth and estimate the probability of extraterrestrial life. A gamma ray burst at 6000 light years would result in mass extinction; a 1000 light year distant burst would be equivalent to a 100,000 megaton nuclear explosion. A burst 100 light years away would blow away the atmosphere, create tidal waves, and start to melt the surface of the earth. There is a one in a million chance that there could be a gamma ray burst as near as the earth's closest star, Alpha Centauri, in the lifetime of the earth. Such a burst, at 4.3 light years distant, would effectively incinerate the earth.