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MoviegoerKinz · 06-22-2009, 06:59 PM

Quote:

Originally Posted by Mistress Vondella

"Thank you for joining us, ladies. Satine, consider my not taking house points off you thanks for bringing the extra supplies for the Hufflepuffs. Rachel, 5 points for arriving late."

He looked around the room again and continued:

Certain star explosions, called hypernovae, have much greater reach. Ten times more powerful than typical supernovae, hypernovae are the source for long-duration gamma ray bursts (GRBs), which are high-energy beams emitted along the dying star's axis. A GRB could travel 6,500 light-years and still inflict terrific damage on Earth, Thomas says.

The number of GRBs is much less than the number of supernovae, but the exact rate in our galaxy is still a matter of debate. A few years ago, a group of astronomers calculated that the likelihood of a GRB going off near us was very low, due to the fact that GRBs tend to arise in young galaxies with less heavy elements than the Milky Way.

But Thomas says that subsequent analyses have called this calculation into question, partly because our galaxy has merged in the past with smaller, younger galaxies that could have brought GRB-ticking-time-bombs in with them. "Our likelihood for hosting a GRB could vary with time," Thomas says.

He speculates that on average a GRB lights up our galaxy about once every 10 million years.

Aislynn was contemplating of asking a question. Why should we listen to what this Thomas had to say, she thought. It was probably some muggle just speculating. Besides Earth has encountered any kind of gamma-ray activity since 2004.

06-22-2009, 06:59 PM	#21 (permalink)
MoviegoerKinz Lupin's ♥ for Tonks Nogtail Join Date: Jul 2005 Location: Mooning Over Lupin Posts: 4,793 Hogwarts RPG Name: Roman J. Lupin First Year	GLEEk Magic Picture Finder Quote: Originally Posted by Mistress Vondella "Thank you for joining us, ladies. Satine, consider my not taking house points off you thanks for bringing the extra supplies for the Hufflepuffs. Rachel, 5 points for arriving late." He looked around the room again and continued: Certain star explosions, called hypernovae, have much greater reach. Ten times more powerful than typical supernovae, hypernovae are the source for long-duration gamma ray bursts (GRBs), which are high-energy beams emitted along the dying star's axis. A GRB could travel 6,500 light-years and still inflict terrific damage on Earth, Thomas says. The number of GRBs is much less than the number of supernovae, but the exact rate in our galaxy is still a matter of debate. A few years ago, a group of astronomers calculated that the likelihood of a GRB going off near us was very low, due to the fact that GRBs tend to arise in young galaxies with less heavy elements than the Milky Way. But Thomas says that subsequent analyses have called this calculation into question, partly because our galaxy has merged in the past with smaller, younger galaxies that could have brought GRB-ticking-time-bombs in with them. "Our likelihood for hosting a GRB could vary with time," Thomas says. He speculates that on average a GRB lights up our galaxy about once every 10 million years. Aislynn was contemplating of asking a question. Why should we listen to what this Thomas had to say, she thought. It was probably some muggle just speculating. Besides Earth has encountered any kind of gamma-ray activity since 2004. __________________ This is how I roll, animal print pants out control. This is how I roll, come on ladies it's time to go!