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What Struck Earth in 775?
ananyo writes "Just over 1,200 years ago, the planet was hit by an extremely intense burst of high-energy radiation of unknown cause, scientists studying tree-ring data have found. The radiation burst, which seems to have hit between 774 and 775, was detected by looking at the amounts of the radioactive isotope carbon-14 in tree rings that formed during the 775 growing season in the Northern Hemisphere. The increase in 14C levels is so clear that the scientists conclude that the atmospheric level of 14C must have jumped by 1.2% over the course of no longer than a year, about 20 times more than the normal rate of variation (abstract). Yet, as the only known events that can produce a 14C spike are supernova explosions or giant solar flares, and neither event was observed at the time, astronomers have a cosmic mystery on their hands."
You need only look at the years leading up to 775 to unravel this mystery. In 773 at the start of the Islamic Golden Age, the number zero was introduced to Baghdad which would, in 775, surpass China's capital of Chang'an as Earth's largest city. Now, we know from the second law of thermodynamics that 'the entropy of an isolated system that is in equilibrium is constant.' Now with all those people suddenly using zero in tons of transactions and writings, Earth experienced a huge decrease in entropy. I'm sure if you analyze the existing works from the time, you'll find that pervasive use of the hot new number zero increased the frequency of numbers at the time by 1.2%. That means that somewhere there had to be an increase in entropy to maintain the balance described by the second law of thermodynamics. Of course, anyone with a mail-order internet degree can tell you the obvious natural source of entropy at the time would be the decay of nitrogen-14. What? Falsifiability? Just watch, the floods in Thailand have lead to a decrease in production of ones and zeros hard drives which means we'll finally get a break from this 'global warming' or (let's just call it for what it really is) the 'entropic energy extravaganza!'
Also, for good measure: Nazis.
My work here is dung.
I don't have a comment other than to say that I enjoy articles like this one. Please bring more like it and i will hit refresh 20 times to get yor page hit count up :)
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
Is that you?
If the supernova was behind or near the Sun, earthlings around 775 wouldn't have been able to detect it.
All ideas^H^H^H^H^Hprocesses in this post are Patent Pending. (as well as the process of patenting all postings)
Would this mean carbon dating is inaccurate for items older than 1300 years?
Time to redate the Shroud of Turin?
Where people making observations of the Sun in 775?
See my blog http://ilovecookes.blogspot.com/ for light hearted technical information.
The Sol system was the site of a major inter-stellar battle. Two great space armadas firing nuclear weapons at each other. Each one trying to gain a foothold in this part of the Western Spiral Arm until of course they realized there was nothing worth it here.
Either that or a Vogon constructor fleet started making a hyper space by-pass. They got the planet between Mars and Jupiter and then the funding ran out.
Undetectable Steganography? Yep, there's an app fo
A Volcano could have spit out the this stuff?
Yet, as the only known events that can produce a 14C spike are supernova explosions or ... and neither event was observed at the time
... was observed at the time in surviving northern written records.
Are there any detailed written astronomical observations from the southern hemisphere from that long ago?
Also it would be pretty funny if the two guys recording solar observations in 775 both had a rainstorm the day of the largest solar flare.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Since a near supernova enough to increase Carbon 14 levels would leave other effects, and the flares explanation is, similarly, weak.It is just as likely there was a temporary reduction in the earth's magnetic field that allowed more ambient cosmic rays to strike earth. While this amount of variation in the magnetic field is high, it isn't out of range of other events. It has the further advantage of not leaving a large number of highly visible effects, except for very strong auroras, which, given the date, might not have been recorded frequently or unequivocally enough.
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Build it, and they will come^Hplain.
Atmospheric nuclear expolisions can also cause a spike in C14... http://en.wikipedia.org/wiki/Carbon-14
The obvious answer is that earth was nuked in the year 775!!!
"Behind the Sun?"
Maximum Prophet, for your information, the Earth rotates around the Sun.
Being behind the Sun may not matter here, if the effect was strong and _long_ enough to elevate C14 levels.
Wrong! Back then, the universe rotated around the earth. Everybody knows that. So it could be perfectly true back then, that this supernova hid behind the sun.
Rimmer: Just cause they're aliens doesn't mean to say they don't have to visit the little boys' room. Only they probably do something weird and alien-esque, like it comes out of the top of their heads or something.
Lister: Well, I wouldn't like to be stuck behind one in a cinema.
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775 was a year of false permissiveness when anyone could read or do anything as long as it was produced by a small cabal known as "the group", headed by "owner".
"I opened my eyes, and everything went dark again"
A.D. 774. This year the Northumbrians banished their king,
Alred, from York at Easter-tide; and chose Ethelred, the son of
Mull, for their lord, who reigned four winters. This year also
appeared in the heavens a red crucifix, after sunset; the
Mercians and the men of Kent fought at Otford; and wonderful
serpents were seen in the land of the South-Saxons.
http://omacl.org/Anglo/part2.html
rewriting history since 2109
First of all, the 14C measurements and related considerations could be simply flawed. It would not be the first time. ... which would require a rather large number of samples to be studied and collected from a wide spread area (the whole northern emishere). I wonder how many (precious) samples of wood can be retrieved intact from 1200 years in the past to be literally burnt in order to measured the 14C.
Second, the fact that the primary natural source of carbon-14 on Earth is cosmic ray action upon nitrogen in the atmosphere doesn't mean it's been a super nova for sure. That could also be due to abnormal solar activity (this is said in the article) which could easily go unobserved by civilizations that don't have the proper technology.
Third, astronomical records at that era were relatively scarce and quite imprecise too.
Fourth, the article talks about northern emisphere
Fifth, you can also have a not-so-strong abnormal solar activity just lasting months or even quarters to produce the same amount of 14C.
But all these could be as flawed as the original considerations ...
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
Richardcm posted this on reddit:
"[The Anglo-Saxon Chronicle](http://omacl.org/Anglo/part2.html) gives this curious entry for the year 774: A.D. 774. ... This year also appeared in the heavens a red crucifix, after sunset; the Mercians and the men of Kent fought at Otford; and wonderful serpents were seen in the land of the South-Saxons.
The Anne Savage translation says 'Men saw Christ's red cross in the heavens after sunset' but in the year 776." Interesting, and noteworthy.
Wrong again. Everyone knows the Earth was flat in 775...so there was no rotation only spinnning. Perfectly plausible to have a supernova hide under the Earth.
Of course, it all makes sense now. The supernove killed all the turtles, so the Earth had no choice but to start rotating.
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The original article links don't provide any useful data to assess the likelihood of either suggested potential cause (supernova or solar flare).
Here is a nice report that does:
http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19690024196_1969024196.pdf also see: http://journals.ametsoc.org/doi/abs/10.1175/1520-0469(1964)021%3C0134%3APOCBSP%3E2.0.CO%3B2
What one finds is that the normal rate of C-14 production is around 2.5 C-14 atoms cm^2/sec, normally 95% of it from solar protons. The large solar flare of 1956 Feb 23, if at an opportune time of reduced shielding (the effective shielding fluctuates), would produce an annualized equivalent of 2.33, which would about double the normal production. The closest recent supernova of 1054 on the other hand is only capable of producing up to perhaps 0.2, only 8% more than normal.
To get a 2000% increase over normal you either need a supernova 16 times closer and 250 times brighter than 1054, or you need one 20-fold super-solar flare, or 20 big normal solar flares at an opportune low shielding period. Whether or not anyone saw or recorded a supernova this close, the remnant would be glaring obvious today - it would be a naked eye object larger than the full moon. On the other hand no one even noticed a solar flare before 1857, except for the auroras seen. It suggests a rare abnormal solar flare, or a rare abnormal series of more typical solar flares is by far the most likely candidate.
As others have noted on this thread, records do exist of strange events in the sky from that time, which might possibly refer to unusual auroras, and records from that time are terribly spotty anyway so the evidence would be expected to be thin, if present at all.
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