scibri (2544842) writes "A few weeks ago, reports of a mysterious spike in carbon-14 levels in Japanese tree rings corresponding to the year 775 intrigued astronomers.
Such a spike could only have been caused by a massive supernova or solar flare, but there was no evidence of either of these at that time. Until Jonathon Allen, a biochem undergrad at UC Santa Cruz googled it.
He found a reference in the Anglo-Saxon Chronicle to a "red crucifix" appearing in the sky in 774, and speculates that it could have been a supernova hidden behind a cloud of dust, which could mask the remnants of the exploded star from astronomers today."
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