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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."
became ye olde incredible hulke...
Depends on intensity I imagine. The article notes it had to be further then 3000 light years away or they'd have expected it to cause an extinction event - and also that there are "short" and "long" GRBs.
But you not like earth when EARTH ANGRY! RAAWWWRR
Did we get struck twice in 775? I bet samzenpus knows.
http://news.slashdot.org/story/12/06/04/1147201/what-struck-earth-in-775
Tic-Tac-Toe, Global Thermonuclear War, and relationships all have the same winning move.
But I'm a Frequentist Statistician, you insensitive clod!
sysadmins and parents of newborns get the same amount of sleep.
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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...why everything tastes like blue.
"Tell me doctor, with all of your defenses, are there any provisions for an attack by killer bees?"
They were really the Glow-In-The-Dark Ages.
FTA: "In the last 3000 years, the maximum age of trees alive today, only one such event appears to have taken place."
The actual oldest trees are about 5,000 (http://en.wikipedia.org/wiki/List_of_oldest_trees)
Though that doesn't devalidate his main point (that this has only happened once in 3,000 years). I just wish he'd fact-check a bit more.
"We cannot treat name-calling as reasoned debate."
That was a line in a speech delivered earlier today. I doubt he was referring to Slashdot specifically, but it's well taken here anyway.
I've heard the 775 C14 anomaly attributed to a very large solar storm period too, even those these guys dismiss the idea.
Neither of the articles discuss what might have happened to living things at the time. Could some people have had radiation sickness for example? Could this have caused mutations?
http://michaelsmith.id.au
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).
Of course for all the preppers out there it should also be said that the closest confirmed GRB is 1.3 billion light-years from Earth, the observation period isn't very long but it's hardly a common occurrence. Which is also why I'm a little sceptic that we've had one right on our doorstep only a few thousand light years away.
Live today, because you never know what tomorrow brings
http://en.wikipedia.org/wiki/774%E2%80%93775_radiation_burst
The part about witness accounts to a red cross like image in the sky, meaning someone may have actually seen the event...
I'd take that with a pinch of salt. I've been reading Tom Holland's "Millennium" and it mentions that one of the Holy Roman emperors (an Otto) was heading down to Jerusalem to hand his crown over to JC when he came down for the second coming, when the army he was with saw a dragon in the sky. They figured this was a portent of bad things, and weren't surprised when Otto died a few days later.
I wouldn't take that anecdote as evidence for dragons though.
"The greatest lesson in life is to know that even fools are right sometimes" - Winston Churchill
That's a bit of a backward way to approach it.
Normally, when we make observations that don't line up with our current understanding (e.g. "Where did all this carbon-14 come from?") we look for explanations. The most likely known sources of carbon-14 spike are GRB's and solar flares. Discounting those because the overall event is unlikely, in spite of the evidence, is what scientist dub "stupid".
http://en.wikipedia.org/wiki/774%E2%80%93775_radiation_burst
The part about witness accounts to a red cross like image in the sky, meaning someone may have actually seen the event...
We'd have to treat that as hearsay as no one around in 774 would be updating wikipedia.
Better check MySpace.
I only crap once per day. The amount of time I sit on the toilet is only about 50 seconds. Considering that there are 86400 seconds in a day, the probability of me sitting on the toilet and crapping at any given moment is extremely small.
Yet here I am, sitting on the toilet and crapping while I type this on my phone. Or since it's so unlikely, is there another explanation for the smell and the splashing sound?
Just the opposite.
Douchebaggery directed against objective truth deserves more harsh response than personal attacks.
Contrary to the popular belief, there indeed is no God.
> Wouldn't it be possible to calculate where that black hole formed in the night sky at the time, and where it is located at the present?
I'm guessing insufficient data. The distance and bearing would need to be established with some precision.
As for finding a stellar-sized black hole 1,000 light years away, unless its effects can be noted, even its peripheral effects would be difficult to observe.
This is why we'll have to be careful once the scientists get off their lazy butts and give us hyperdrive. There you are, zipping along, and all of sudden, "chomp," you get eaten by an uncharted black hole. :)
Cogito, igitur comedam pizza.
There was another event that led to modification of the natural isotopes in North America:
http://ie.lbl.gov/paleo/paleo.html
http://abob.libs.uga.edu/bobk/nuclear.html
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also, couldnt a grb at worst wipe out life on just half the planet? Surely if you're on the "dark side of the earth" for this event, you would be safe.
Sure, if you can build the 40,000 km long, 30 km high wall around the terminator fast enough to prevent your part of atmosphere from getting spoiled with all the NO2 generated by the gamma burst interacting with the atmosphere.
Ezekiel 23:20
no, there is still Eta Carinae 7800 light years away, and if it is part of binary system there is non-zero chance the pole might be oriented at earth when it blows. That would produce ten times lethal dose for anything on that side of Earth when it goes. It is near the end of its life and could hypernova at any time.....
Well, IIRC from the book, basically everything on the facing side of the earth would be dead and on fire. It would also entirely destroy the ozone layer in that hemisphere. Once the atmosphere had equalized, what would be left wouldn't be enough to protect the survivors from the sun, so they'd all die too, just more slowly and painfully.
The enemies of Democracy are
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".
I would still call it an article if it just contained the word "the".
I am anarch of all I survey.
I would still call it an article if it just contained the word "the".
Definitely.
The enemies of Democracy are
The concentrations would have to be startlingly high to actually wipe out all surface life. Even then, the life that doesn't breathe, or lives in the ocean, or just isn't as badly affected as large mammals would be just fine.
From here:
Google: Get to know it. Make it your friend.
Specifically... the risk of crashing into solid matter that doesn't emit or reflect light.
I see that you too own a black lab that sleeps between the bed and the bathroom...
How come Slashdot never gets Slashdotted?