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Earth May Have Been Hit By a Gamma-Ray Burst In 775 AD

The Bad Astronomer writes "Studies of carbon-14 in Japanese trees and beryllium-10 in Antarctic ice indicate the Earth was hit by a big radiation blast in 775 AD. Although very rare, occurring only once every million years or so, the most likely culprit is a gamma-ray burst, a cosmic explosion accompanying the birth of a black hole. While a big solar flare is still in the running, a GRB from merging neutron stars produces the ratio of carbon and beryllium observed, and also can explain why no bright explosion was seen at the time, and no supernova remnant is seen now."

4 of 157 comments (clear)

  1. Re:Umm? How far away would it have been? by Chris+Burke · · Score: 5, Informative

    I thought a nearby GRB would wipe out all life, all the way down to viruses.

    It would. But if it was farther away, it would just create a bunch of radioactive isotopes in the upper atmosphere while leaving life on the ground mostly unmolested.

    If only someone had an estimate of how far away this one was, and had presented it in something that would describe this news item in detail. We could call it an "article".

    For non-douches who also didn't RTFA, it's estimated at 3000 to 13000 ly away. For comparison, in Phil's book "Death from the Skies" he discusses what would happen as a result of a GRB from 100 ly away, and the result is Very Bad(tm).

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  2. Now we know by Anonymous Coward · · Score: 5, Funny

    They were really the Glow-In-The-Dark Ages.

  3. Re:How many times did this happen? by Anonymous Coward · · Score: 5, Informative

    This is not a dupe, the first article pointed to tree rings, the second confirms the results using Antarctic ice.

  4. Re:Effects on Humans and animals by Megahard · · Score: 5, Funny

    It killed off all the creatures that only lived back then - dragons, elves, fairies, witches and the like.

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