Auroras are seen when bursts of charged particles hit Earth's atmosphere -- but there is no record of these occurring at the same time as the 14C increase in tree rings. ©Nasa
Posted on 06/04/2012 10:58:45 AM PDT by SunkenCiv
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 AD 774 and AD 775, was detected by looking at the amounts of the radioactive isotope carbon-14 in tree rings that formed during the AD 775 growing season in the Northern Hemisphere. The increase in 14C levels is so clear that the scientists, led by Fusa Miyake, a cosmic-ray physicist from Nagoya University in Japan, 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...
The only known events that can produce a 14C spike are floods of γ-rays from supernova explosions or proton storms from giant solar flares. But neither seems likely, Miyake says, because each should have been large enough to have had other effects that would have been observed at the time.
A massive supernova, for example, should have been bright enough to produce a 'new' star visible even in the daytime, as was the case for two known supernovae in AD 1006 and AD 1054. Such an explosion would have needed to be brighter than either of these, Miyake says, because those events were not large enough to leave traces in the 14C record.
It is possible, he says, that the proposed event might have occurred in the far southern skies, where astronomers of the era wouldn't have seen it. But still, he says, if it did happen, today's X-ray and radio astronomers should have found signs of a "tremendously bright" remnant of the explosion.
(Excerpt) Read more at nature.com ...
Auroras are seen when bursts of charged particles hit Earth's atmosphere -- but there is no record of these occurring at the same time as the 14C increase in tree rings. ©Nasa
In the late eighth century, Earth was hit by a mystery blast of cosmic rays, according to a Japanese study that found a relic of the powerful event in cedar trees. Analysis of two ancient trees found a surge in carbon-14 -- a carbon isotope that derives from cosmic radiation -- which occurred just in AD 774 and AD 775, the team report in the journal Nature on Sunday. Earth is battered by protons and other sub-atomic particles which are blasted across space by high-energy sources. The particles collide with the stratosphere and react with nitrogen to create carbon-14, which is then absorbed into the biosphere. A team led by Fusa Miyake of Nagoya University found that levels of carbon-14 in the two cedars were about 1.2% higher in 774 and 775 compared to other years... the cosmic whack of 774-775 cannot be attributed to the Schwabe cycle of the time -- and it is far bigger than any known flare from the Sun. The other possibility is a supernova, or a star that explodes at the end of its life in a welter of gamma radiation. They intend to fine-tune the search for the source by looking at telltale traces of beryllium and nitrate isotopes. They also plan a wider search of historical documents to see if, 1,237 years ago, anyone noted a strange flare in the sky. [ Ancient cedar trees hold 8th-century mystery, AFP ]
Credit: Wikimedia
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| GGG managers are SunkenCiv, StayAt HomeMother & Ernest_at_the_Beach | |
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Thanks Renfield et al. :') |
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No novas or super-novas recorded during that period of time?
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The Cycle of Cosmic Catastrophes:
Flood, Fire, and Famine
in the History of Civilization
by Richard Firestone,
Allen West, and
Simon Warwick-Smith
There are actually non fossilized cedar trees out there that are 1300 years old?
Wow!
A Celestial CollisionEarly in the evening of June 18, 1178, a group of men near Canterbury, England, stood admiring the sliver of a new moon hanging low in the west. In terms they later described to a monk who recorded their sighting, "Suddenly a flaming torch sprang from the moon, spewing fire, hot coals and sparks." In continuing their description of the event, they reported that "The moon writhed like a wounded snake and finally took on a blackish appearance"... [P]lanetary scientist Jack Hartung of the State University of New York... gathered enough clues to suggest that a large asteroid... might have smacked into the moon just over the horizon on the back side. To test his suspicion, Hartung went to the Lunar and Planetary Institute in Houston, and inspected Russian and American photographs of the moon's back side. Sure enough, in just the right place, he found a remarkably fresh crater, 12 miles across and twice as deep as the Grand Canyon. From it radiated white splatter marks for hundreds of miles... Such an impact, reason astrophysicists, would set the moon to ringing like a gong for thousands of years... At Texas' McDonald Observatory, astronomers Odile Calame and J. Derral Mulholland of the University of Texas find that the surface of the moon moves back and forth fully 80 feet! Such an oscillation clearly implies a collision with something large, sometime within the not-too-distant past, probably within the memory of mankind. The problem is that there is no way to peg the date exactly at 1178.
by Larry Gedney
February 10, 1983
That was 75 million years ago...
“The radiation burst, which seems to have hit between AD 774 and AD 775”
Were they prototyping the Fukushima Daiichi reactors then?
We Are All Going To Die
(in case it wasn't obvious, /s)
The end is near.
I’m gonna reach around and scratch mine, then kiss it goodbye. But not until I vote a few people out in November and use some of the coupons I’ve been collecting.
Not, at least, from where it could have been seen from the northern hemisphere, which is where much of the remembered astronomy was happening.
It might be interesting to research some of the mythology or remembered lore of southern hemisphere peoples to see if anything might be connected.
LOL! Somebody had to post “it”!
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