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© Keith Vanderlinde/NSF/Antarctic SunIce cores from the Earth's polar regions may contain chemical traces of ancient supernovae.

Japanese scientists have journeyed to Antarctica to recover evidence of alterations to Earth's atmosphere, caused in medieval times by supernovae recorded by ancient scholars - including obscure Irish monasteries where monks later interpreted them signs of the Antichrist. No, this isn't the plot of the next Dan Brown novel (or a Dan Brown fan-fiction written by an X-Files addict): this is real science.

Supernovae release terrific amounts of energy, as in "If one happened too close the planet would be sterilized" truly terror-inducing terrific. Some of this energy is fired off as gamma rays, which can travel thousands of light-years and still pack enough of a punch after to alter the atmosphere - which is exactly what happened in 1006 and again in 1054, when gamma rays blasted the upper atmosphere and created spikes in NO3 levels. There was also quite a lot of visible light, creating a star visible even during the day which was noted by various Chinese, Egyptian and even monastic records.

To access past records of the atmosphere, a team of Japanese scientists carefully extracted 122 meters of ice core from Antarctica. Even better, to locate events on such a stretch of frozen time you use known volcanic atmosphere-altering events as reference points - in other words, these guys use exploding mountains as a ruler.

The team found NO3 spikes at times corresponding to 1006 and 1054, as well as a mysterious unknown third event - and we remind you that this is not a movie, even though that sounds so much like a second act reveal leading to a lost city or something, we can practically see Nicolas Cage's shocked expression.

Unlike any movie adventurer of the unknown, who has a tendency to steal/detonate every single relic they find, the Japanese team have also made things easier for anyone who follows them. The unprecedented detail of their observations reveals a standard 11-year cycle in ice-core records, corresponding to the sunspot cycle. This will help future ice-core observers track the time of events.

These people look at timescales so huge that the pulsing of the sun itself is just the ticking of a clock.