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Earth Space Science

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."
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What Struck Earth in 775?

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  • Behind the Sun? (Score:5, Insightful)

    by Maximum Prophet ( 716608 ) on Monday June 04, 2012 @08:54AM (#40207613)
    If the supernova was behind or near the Sun, earthlings around 775 wouldn't have been able to detect it.
  • by h4rr4r ( 612664 ) on Monday June 04, 2012 @09:04AM (#40207733)

    Why do we care when a poorly made fake was made?

    Your first question is more interesting.

  • by Anonymous Coward on Monday June 04, 2012 @09:26AM (#40207927)
    If I do it'll be because I think it's funny; not because you say so.
    I really wish people would stop with this sort of thing.
  • Re:Behind the Sun? (Score:5, Insightful)

    by Lumpy ( 12016 ) on Monday June 04, 2012 @09:37AM (#40208035) Homepage

    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..

  • by TheCarp ( 96830 ) < minus pi> on Monday June 04, 2012 @09:59AM (#40208243) Homepage

    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".

  • by EasyTarget ( 43516 ) on Monday June 04, 2012 @10:10AM (#40208355) Journal

    "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.

  • by philip.paradis ( 2580427 ) on Monday June 04, 2012 @10:17AM (#40208437)

    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.

  • A few hints (Score:5, Insightful)

    by aglider ( 2435074 ) on Monday June 04, 2012 @10:18AM (#40208447) Homepage

    First of all, the 14C measurements and related considerations could be simply flawed. It would not be the first time.
    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 ... 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.
    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 ...

  • by mrsquid0 ( 1335303 ) on Monday June 04, 2012 @10:19AM (#40208465) Homepage

    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.

  • by Unordained ( 262962 ) <> on Monday June 04, 2012 @10:34AM (#40208629)

    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?

  • by Impy the Impiuos Imp ( 442658 ) on Monday June 04, 2012 @10:45AM (#40208769) Journal

    > 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.

  • by N0Man74 ( 1620447 ) on Monday June 04, 2012 @10:56AM (#40208887)

    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.

  • by DinDaddy ( 1168147 ) on Monday June 04, 2012 @12:50PM (#40210241)

    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".

  • by DinDaddy ( 1168147 ) on Monday June 04, 2012 @12:54PM (#40210291)

    Carbon 14 dating assumes that the half-life is fairly constant,

    No it doesn't. It accounts for events like this.

  • by just_common_sense ( 2485226 ) on Monday June 04, 2012 @04:32PM (#40213191)
    That's a straw man. You're forming a mental picture of how the "real thing" would look like and then disproving it. The fact is, nobody really knows how the image on the Shroud was formed.

    What surprises me is that there isn't any reasonable explanation (that I know of) for how such a fake could be produced, even though the Shroud is perhaps the most studied artifact in our history. There's pretty good evidence that the image isn't painted. (For instance, the VP-8 image analysis shows a "3D" quality and the image only exists on the surface of the fibers.) So how was it made? If you know of any theories that account for everything, I'd be glad to hear them.

    From what I've heard, the recreations fail in major ways, even though our technology is far, far better than what they had in the middle ages. ;-) If I'm wrong about that, please provide an example. I'd also like to point out that in the middle ages, they didn't have the types of analysis we have today, and would have had no reason, for instance, to fake aspects that can only be seen on the microscopic level.

    I honestly don't know whether the Shroud is a forgery or not, but I've always been quite overwhelmed by the amount of evidence that suggests it is not.

Help! I'm trapped in a PDP 11/70!