What Struck Earth in 775? 344
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."
Quite Obvious, Even to Me (Score:5, Funny)
Also, for good measure: Nazis.
Re:Quite Obvious, Even to Me (Score:5, Funny)
Flooding in Thailand? That's just the rumblings of Cthulhu in his city of Rl'yeh.
Also, as far as what hit Earth in 775, that was plainly a time-travelling Chuck Norris.
Re: (Score:3)
Solar flare from Bernard's Star in our direction
Re: (Score:2)
I was going to answer "Tesla and one of his experiments" but your explanation works for me.
Re: (Score:2)
I was going to answer "Tesla and one of his experiments" but your explanation works for me.
Presumably the experiment involving time travel.
Re:Quite Obvious, Even to Me (Score:4, Funny)
But his name was Josef Gottsdamm before, and he was a plumber from Sheissburg.
Re:Quite Obvious, Even to Me (Score:5, Funny)
Couldn't've been, Hitler is still in my textbooks.
Duh. We have to go back and rescue him every time one of you noobs gets your time travel license.
Re:Quite Obvious, Even to Me (Score:5, Funny)
All that means is that whomever time traveled failed to kill Hitler.
Of course, the world has a way of self correcting so even if we had killed Hitler we'd just be dealing with someone else.
No... to thoroughly get rid of Hitler was must first eliminate the conditions which lead to the Nazi rise in power. To do that it would be desirable to avoid the punitive nature of the Treaty of Versailles. Though to avoid that we really need to have avoided the first World War. Obviously, the best way to avoid that is too prevent Duke Ferdinand from being assassinated....
Frankly, I don't want to continue stepping backwards but suffice it to say, I think the best course of action is to go back far enough to find the first homo sapiens and brutally murder them all. That should prevent Hitler from creating the Holocaust.
Re:Quite Obvious, Even to Me (Score:5, Funny)
Re:Quite Obvious, Even to Me (Score:4, Funny)
Success!!!
(and tell your grandmother I said "Hi")
Just kidding, she wouldn't speak to me at the high school dance...
Re:Quite Obvious, Even to Me (Score:5, Funny)
Re: (Score:3)
My hat is off to you, sir. You clearly understand time cube.
Re:Quite Obvious, Even to Me (Score:5, Funny)
All I see is the universal Linux file permission.
Re:Quite Obvious, Even to Me (Score:4, Funny)
Exactly. In 773, the world had write and execute permissions--clearly a mistake. Mankind tried to correct this error in 774 by making it read-only for the world, but it was too late. By then the world had already installed its payload--a virus for the ages, unlike any that had ever been seen before. There was nothing to be done once the execution bit was enabled in 775 except to mourn for the dead. The cycle is set to repeat itself every 777 years.
Mind blown.
Re: (Score:3)
I'm not saying it was aliens, but it was aliens. Obligatory Giorgio A. Tsoukalos reference.
Re: (Score:2)
Re:Quite Obvious, Even to Me (Score:5, Funny)
With that much carbon, it must have been a wet one.
More articles like this one (Score:5, Interesting)
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 :)
Re:More articles like this one (Score:5, Funny)
I don't know, I've read the article and it's still not clear to me whether an iPhone or Android is better, who to vote for, whether I should be mad at banks and who to vote for.
On a more serious note, I wholeheartedly agree.
Re:More articles like this one (Score:4, Funny)
I don't know, I've read the article and it's still not clear to me whether an iPhone or Android is better, who to vote for, whether I should be mad at banks and who to vote for.
Whether an iPhone or Android is better: Yes. While both iPhones and Android phones also emit radiation, that radiation is for sure less harmful than the high-energy radiation from this event.
Who to vote for: It was an event of huge radiation. Radiation is bad, so to prevent such radiation in the future, you should vote for the Green: Since they are against radiation, they will certainly make sure that such a disastrous event (so disastrous that even the records about it got destroyed!) won't happen again.
Whether you should be mad at banks: Banks usually have security personnel, therefore being mad at that place might not be a good idea. On the other hand, if you are a danger to yourself when going mad, it may be a better idea to be mad at a bank than when alone at home. Just make sure it's not your bank you get mad at, because they might not let you in again afterwards.
Who to vote for: Well, this was possibly caused by solar flares. Now the Green are all for solar energy, which, as this event shows, is not without danger. Therefore you should vote for anyone but the Green.
SCNR :-)
Re: (Score:2)
Re: (Score:3, Insightful)
> I enjoy articles like this one. Please bring more like it.
You want more articles about huge things hitting the Earth?!?!??
I'd just as soon there be not much to write about.
Lavos (Score:5, Funny)
Is that you?
Re: (Score:2)
By total coincidence, I just came here from ordering the CT remake on DS. Apparently this cosmic ray burst happened to make me feel special today.
Behind the Sun? (Score:5, Insightful)
Re: (Score:3, Informative)
If there was a supernova around then, then there would be remnents of a supernova that we could date back to then, right? We would be able to observe the remnents today and work back to about when that particular star died, even if it wasn't observed back in 775, right?
Re: (Score:3, Funny)
First, we need a llama and then lots and lots of bubble wrap.
Re: (Score:3)
Big magnet and a big fan.
Re:Behind the Sun? (Score:5, Funny)
that is a great idea...
now how do you propose to find this one particular needle in a giant haystack?
Maybe we could start by looking for elevated 14C level's in the tree rings?
Circular evidence is still evidence right?
Re: (Score:3)
Circular evidence is still evidence right?
Of course it is. Though technically, tree rings aren't perfectly circular. There tends to be a fair amount of variation, primarily due to environmental factors. Perhaps we should compromise and just call it 'oblong evidence'.
Re: (Score:3)
Re:Behind the Sun? (Score:5, Insightful)
You cant see a Gamma Ray burst. Sorry the real world is not like SCI-Fi.
And no, they would not see it. Can you see ANY nebula in the night sky with your eyes? there are several that are LARGER than the moon up there if they were visible to the eye, but require a camera to show them, something that did not exist back then. Supernovae dont stay lit in the sky for a very long time they fade out to below human visibility within a short time and if it was close to the viewing line of the sun, Nobody would have ever seen it even if it was Lit up for a few weeks..
Re:Behind the Sun? (Score:5, Informative)
Yes, there are. Orion, Pipe, Eta Carinae and Coal Sack are four you can see with the naked eye. Granted, the people back then wouldn't have known they were nebulas, but those objects were still visible in the night sky.
Re:Behind the Sun? (Score:5, Informative)
Re:Behind the Sun? (Score:4, Informative)
Unfortunately M42 is not visible from around here, and most people cant spot it until it is pointed out, even in low light pollution areas. People in general dont notice. But the trained eye certainly can, like you point out.
But, IT would have to be brighter than -2.5 to be seen from Earth during full daylight. Anything near the sun within several sun widths would have to be ungodly bright to even be noticed. Even during a 2 month period a close supernovae would be unnoticed. The could would not stay at -2.5 for very long, so even if it was a super bright -1 it would be close to 6 months before it would swing around into twilight.
You could have a 4.5 month period of not being able to see it. Plenty of time for a distant one to dim considerably.
Re: (Score:3)
One cannot see the gamma-ray part of a gamma-ray burst, but one can see the afterglow, and afterglows can be very bright. A typical optical afterglow from a gamma-ray burst lasts for several days, and can be brighter than a supernova. If a gamma-ray burst did cause this burst of radiation then it is quite reasonable that the optical afterglow would have been seen. However, if the burst did occur behind the Sun then, because the afterglow fades very fast, it is possible that the afterglow would have faded
Re:Behind the Sun? (Score:5, Interesting)
If a GRB went off in the Galaxy then a few years of increased radioisotopes would be the least of the indicators. A mass extinction would be associated with such an event as most of the ionosphere would be striped from the Earth causing cosmic rays to reach the surface, this would have dramatic and lasting effects on life. I also neither implied nor stated that this was associated with a GRB.
While supernova do not "stay lit in the sky for a very long time" you need to scale that with your time scale of the event. The Crab Nebula is the result of a supernova that went off in 1054 [wikipedia.org] (Earth time) and was visible to the human eye for a period of approximately 2 years after it went off. There is no associated increase in radioisotopes for that event, thus indicating that a larger (likely closer as well) event would have to be the cause of the increased radioisotopes observed in 775.
Re: (Score:3)
And if it was in line with the galactic disc it can easily be hidden from the dust and all the light pollution from our galaxy, Very good point.
Re: (Score:3)
Gamma rays wouldn't form C14, only neutrons that got caught in the nuclei.
Re: (Score:2)
Re:Behind the Sun? (Score:5, Informative)
Nearby supernovae appear as one of the brightest objects in the sky for a few days to a week. The remnants remain visible for months, and then have a habit of leaving a nebula behind.
The Earth travels slightly more than one degree of its orbit per day; The Sun, as seen from the Earth, subtends half a degree of arc. In the absolute worst case, the sun couldn't completely "hide" a supernova for more than a single day; and half a week later, the supernova remnant would dominate the dusk (or dawn) as the brightest thing in the sky except possibly the moon.
Re: (Score:3)
Mea culpa - make that slightly less than one degree per day.
Re:Behind the Sun?! (Score:5, Funny)
"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.
Re:Behind the Sun?! (Score:5, Funny)
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.
Re:Behind the Sun?! (Score:5, Funny)
Of course, it all makes sense now. The supernove killed all the turtles, so the Earth had no choice but to start rotating.
Effect on Carbon dating? (Score:5, Interesting)
Would this mean carbon dating is inaccurate for items older than 1300 years?
Time to redate the Shroud of Turin?
Re:Effect on Carbon dating? (Score:5, Insightful)
Why do we care when a poorly made fake was made?
Your first question is more interesting.
Re: (Score:3)
Re:Effect on Carbon dating? (Score:5, Informative)
Would this mean carbon dating is inaccurate for items older than 1300 years?
Things that were alive in 775 appear to have more C14 than usual, so even after centuries of decay, they'd still have more C14 than usual, which would make them measure younger. This is my understanding from reading the "Amateur Scientist" column in "Scientific American" about doing radiocarbon dating at home. SciAm used to be a pretty cool magazine, well, 50 years ago. When I was a high school kid I spent about two weeks one summer reading on microfilm pretty much every Amateur Scientist column from the 30s (when it was all telescopes) until the 70s when it started sucking. You can buy a collection of those columns on a cdrom now, of course.
Time to redate the Shroud of Turin?
I'm not up on my mythology, but I think it's made of woven plant or animal fibers, and this would have no effect unless the plants or animals that made it were alive in 775. If it was grown in 775, then it would be misdated to be somewhat younger. I might misremember but isn't the mythology something along the lines that it was grown just a short time before year 0 ? This error is going in the opposite direction then. Or theres some alternate mythology as regards templars and freemasons and such, which is too recent to be fixed by the error.
Or the TLDR summary version of the above is ... "no, and no".
Re:Effect on Carbon dating? (Score:5, Insightful)
No, it's not demeaning, unless you define "demeaning" as failure to place higher value on political correctness than scientific examination of things based on evidence. Beliefs being heartfelt doesn't make them scientifically valid, and oftentimes seems to result in irrational adherence to said beliefs. This occurs in the face of absolute lack of supporting evidence for said beliefs, and/or overwhelming evidence to the contrary.
Re: (Score:3)
It's half in the usage and half in the reception. Using "mythology" as a descriptor for various religions *can* be offensive to religious folks because "mythology" typically makes one think of the Greek myths and the like. Nobody likes to have their religion compared to obviously metaphorical legends from a couple thousand years ago.
What these offended believers don't understand is "mythology" is a neutral term, used to describe a belief system not rooted in fact. If you are offen
Re:Effect on Carbon dating? (Score:5, Insightful)
Curious why you posit a difference between modern religions vs. older Greek religions that leads you to label the latter unequivocally as myths? Maybe I am reading a distinction you did not intend, but I would have said "makes one think of older Greek religions which are now accepted as myths".
Re: (Score:3)
Both ancient and more modern religious stories can be correctly labelled as "myth", assuming the intended definition is: "a traditional or legendary story, usually concerning some being or hero or event, with or without a determinable basis of fact or a natural explanation, especially one that is concerned with deities or demigods and explains some practice, rite, or phenomenon of nature." http://dictionary.refer [reference.com]
Re:Effect on Carbon dating? (Score:5, Insightful)
No. A myth is still a myth no matter how many people believe that it is not. If two billion people started to believe that the world was gnawed out of a carrot by The Great Rabbit, it would still be just a myth.
Re:Effect on Carbon dating? (Score:5, Funny)
The Great Rabbit will protect me.
Re: (Score:3)
Re: (Score:3)
He's not calling Christianity a myth, just the backstory of the Shroud of Turin. And the number of people who believe the Shroud of Turin is actually Christ's burial shroud is quite a bit smaller than the number of Christians in the world.
That said, though, "myth" has two definitions: one is a "false belief", but the other is "a traditional story, especially concerning early history or origins, typically involving the supernatural", with no judgement made on the story's truth or falsehood. The New Testame
Re:Effect on Carbon dating? (Score:5, Insightful)
Just a side comment, but don't you think it's a little insulting to tell scientists who've put blood and sweat into these scientific discoveries that they need to pander to the religious, to pretend to hold some doubt, to lie that they wish they were wrong, to equivocate when no equivocation is really required, to imply and insinuate and hint rather than outright state what they know (inasmuch as you can know anything -- they'll grant you that), just to make people less sad about the religion they have merely because of the location of their birth and the (recursive) beliefs of their ancestry? I'm not normally one to go and try to de-convert the religious (my parents were missionaries, I'd rather just leave peole alone), but does that mean we have to be on eggshells? Besides -- the religious all feel free to call each other's religions (N) mere mythology and outright lies, why should we hold back about N+1 beliefs?
Re:Effect on Carbon dating? (Score:5, Insightful)
Just a side comment, but don't you think it's a little demeaning to dismiss the heartfelt beliefs of major segments of today's human population as "mythology"?
Is it only demeaning if the beliefs are held by a major segment? There are still people who believe in or honor the Norse gods too, but I have yet to hear anyone get upset about the phrase "North Mythology".
Listen, I fully support anyone's right to believe in whatever crazy thing they want (as long as nobody nobody else is being hurt or deprived of rights in the process) but that doesn't mean that I have to legitimize anyone's myths or handle its believers with kids gloves, whether the a vast majority or a tiny minority.
Re:Effect on Carbon dating? (Score:5, Interesting)
Is it only demeaning if the beliefs are held by a major segment? There are still people who believe in or honor the Norse gods too, but I have yet to hear anyone get upset about the phrase "North Mythology".
I'll give you your report about Norse mythology getting people upset, then. During my time in the Army I got to spend some time doing joint ops with the Norwegian military. I was given stern warnings by my buddies that the guys wearing hammer tattoos in the bar on base were not safe to taunt regarding their religion. Reason given: it's likely to get a violent response. I'm sure that when they're sober they would take some friendly ribbing just fine, but I felt no desire to see how a drunk Thor worshiper would react to being ridiculed at their base's bar for believing in a myth.
Re: (Score:3)
Welcome to Slashdot. Please check your cultural baggage at the door.
We only allow sacred cows with names like "Mac" and "PC" and "Emacs" and "VI" in here - And even those, we'll still butcher and barbecue if it suits our whims.
Re: (Score:3)
Have you ever even thought of any of the accounts of Rama or Vishnu, say, as being "Hindu myths"?
Surprisingly, no. I spent a year in Thailand, a Bhuddist country, and I have the utmost respect for them. Especially one Bhudist priest; I'll recount a story but you'll surely think it's bullshit, because if I hadn't experienced it myself I wouldn't believe it. I probably recounted this story elsewhere, but here it is.
I was out in the boonies by the ocean visiting some Thai friends, and waited by the side of the
Re:Effect on Carbon dating? (Score:5, Insightful)
"Would this mean carbon dating is inaccurate for items older than 1300 years? "
No; RC dating uses lots of correction tables to account for events like this (this is not the only such event, just the biggest one that is not explained) and for natural/cyclic variations in C14. So the effects of this will already be catered for when computing dates; it's just the 'WTF' of the event itself being discussed here.
Re:Effect on Carbon dating? (Score:5, Informative)
No, scientists have known for a long time that the 14C creation rate isn't quite constant, and have taken this into account in order to do accurate radiocarbon dating. In fact, it was by looking at this carbon-dating calibration curve that they first noticed something unusual in 775.
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature11123.html [nature.com]
Re:Effect on Carbon dating? (Score:5, Insightful)
Carbon 14 dating assumes that the half-life is fairly constant,
No it doesn't. It accounts for events like this.
Solar telescopes? (Score:3)
Where people making observations of the Sun in 775?
Re:Solar telescopes? (Score:5, Funny)
No. The sun was completely invisible until 1013.
Re:Solar telescopes? (Score:5, Funny)
The Police wrote a song about that, IIRC.
Re: (Score:2)
I take it that blindness was a common occupational hazard for those observers.
Re:Solar telescopes? (Score:5, Insightful)
I really wish people would stop with this sort of thing.
Re:Solar telescopes? (Score:4, Funny)
Mod parent insightful!!!!
Re: (Score:3)
Re: (Score:2)
http://en.wikipedia.org/wiki/Solar_flare#History [wikipedia.org]
Says that the first observation of a solar flare didn't take place until the 1800s.
I am not all that sure about duration of such events but what if it had only been visible from the Americas? You still have the other effects but missing direct observation or no surviving data from direct observation seems very possible.
Re:Solar telescopes? (Score:4, Informative)
Where people making observations of the Sun in 775?
Considering that the Camera Obscura [wikipedia.org] dates back to at least 400 BCE, I would say yes, yes there were.
It is Quit Obvious (Score:5, Funny)
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.
Re: (Score:3)
doesn't even need to be in this galaxy. a shot fired and missing will just keep travelling until it hits something.
Re: (Score:3)
Re: (Score:2)
I read a book once, it was about UFO's, ancient Chinese flying carts, and an ancient nuclear war. Maybe that is it!
Volcano? (Score:2, Interesting)
A Volcano could have spit out the this stuff?
Re: (Score:3)
A Volcano could have spit out the this stuff?
Stop that! Stop that!
You're not going to talk about Scientology while I'm here.....
Southern hemisphere supernova (Score:5, Interesting)
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.
Re:Southern hemisphere supernova (Score:5, Informative)
In 775 the Maya [wikipedia.org] were almost certainly making astronomical observations. In the Eastern Hemisphere, I had to Google a bit but the Srivijaya [wikipedia.org] Empire would have had a strong interest in astronomy for navigational purposes. But neither the Maya nor the Srivijaya civilizations have near as many surviving records as do European or Chinese civilizations of the same period.
Re: (Score:3)
If it was a supernova, the Arabs and Indians were writing a lot about astronomy at around that time, and were observing from latitude 30 degrees or so. From there, they would be able to see over 90% of the sky, all but the area right at the south celestial pole. So odds are they'd have seen it. Also, the full scientific article points out that if a supernova had occurred close enough to cause the 14C spike, it would still be bright and obvious today. And while medieval Arabs might miss something, our mo
Neither explanation is likely (Score:5, Interesting)
Re:Neither explanation is likely (Score:4, Interesting)
It has the further advantage of not leaving a large number of highly visible effects
What about geological magnetic field records?
http://en.wikipedia.org/wiki/Magnetostratigraphy [wikipedia.org]
A lot of the initial geomagnetic reversal theory was figured out by basically plotting magnetic field strips across the sea floor using pretty crude equipment. Screwing around with the field that much would seem easy to detect now?
I had a geologist roommate once... I know just enough about geology to be really dangerous (like programmer with screwdriver)
here's your explainatiion (Score:2)
I've checked this several times and it always comes out the same. It's factually correct, so it must be the explanation.
Re:Neither explanation is likely (Score:5, Informative)
Yeah, this probably won't work. Magnetostratigraphy typically gives you information about changes taking place over the timescale that rock formations are created -- millions of years. Those seafloor magnetic field stripes are 100,000 to a million years wide.
That said, if you found a place with intense, continuous volcanic activity, like Hawaii or Iceland, you might be able to find a series of lava flows the right age that would preserve the magnetic field data. The problem would be precisely dating the lava flows -- you can't use 14C dating for that.
New model of spaceship that year for the grays (Score:2)
They bought the budget model that didn't include the extra shielding.
Aliens! (Score:4, Informative)
--Red Dwarf, "Kryten"
Obligatory final line (Score:3)
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.
There's one other thing that can cause a spike... (Score:2)
Atmospheric nuclear expolisions can also cause a spike in C14... http://en.wikipedia.org/wiki/Carbon-14 [wikipedia.org]
The obvious answer is that earth was nuked in the year 775!!!
The star of Bethlehem (Score:2)
What was left of it took 775 years to get to earth.
The Empire blew up Alderaan (Score:2)
Year of Permissiveness (Score:5, Insightful)
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".
well (Score:5, Informative)
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 [omacl.org]
Re: (Score:3)
Re: (Score:3)
Agreed it's not reliable, but texts that old rarely are. It does, however, mean that "no observation" of an astronomical phenomenon becomes either "probably no observation" or "no usable observation". These sorts of records get pinned to actual astronomical events by a mix of confirmation bias and sheer number - record enough events and some are bound to have actually happened, record enough things that can be interpreted as events and some are bound to be interpreted that way because they coincide with act
A few hints (Score:5, Insightful)
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 [wikipedia.org] 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 ...
Re: (Score:3)
With corroborating evidence from a different dataset, measured by different authors, based on trees in Europe and North America.
That right there eliminates most (but not all) of the chance of experimental error. If it was just "hey we measured these two Japanese trees", it wouldn't be published in Nature.
Here Is Some Useful Data (Score:3)
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 [nasa.gov] also see: http://journals.ametsoc.org/doi/abs/10.1175/1520-0469(1964)021%3C0134%3APOCBSP%3E2.0.CO%3B2 [ametsoc.org]
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.