Text clue to ancient radiation spike
An eerie "red crucifix" seen in Britain's evening sky in ad 774 may be a previously unrecognized supernova explosion — and could explain a mysterious spike in carbon-14 levels in that year's growth rings in Japanese cedar trees. The link is suggested today in a Nature Correspondence by a US undergraduate student with a broad interdisciplinary background and a curious mind1.
A few weeks ago, Jonathon Allen, a biochemistry major at the University of California, Santa Cruz, was listening to the Nature podcast when he heard about a team of researchers in Japan who had found an odd spike in carbon-14 levels in tree rings. The spike probably came from a burst of high-energy radiation striking the upper atmosphere, increasing the rate at which carbon-14 is formed (see 'Mysterious radiation burst recorded in tree rings').
But there was a problem: the only known causes of such radiation are supernova explosions or gigantic solar flares, and the researchers knew of no such events in ad 774 or 775, the dates indicated by the tree rings....
comments powered by Disqus
- 150 years later, schools are still a battlefield for interpreting Civil War
- Where are America's memorials to pain of slavery, black resistance?
- Richmond split over Confederate history
- The World's Jewish Population Is Nearing Pre-Holocaust Levels
- Bernie Sanders’s Revolutionary Roots Were Nurtured in ’60s Vermont
- Did a historian who said he’s a victim of McCarthyism get the story wrong?
- Stephanie Coontz’s work on the history of marriage cited by the Supreme Court.
- How Does It Feel To Have One’s Work as a Historian Cited by the Supreme Court? Cool. Very Cool. Thank You Very Much.
- NYT History Book Reviews: Who Got Noticed this Week?
- David Hackett Fischer wins $100,000 prize for lifetime achievement in military writing