Researcher points to Sun as likely source of eighth-century 'Charlemagne event'
Friday, November 30, 2012 - 08:31
in Astronomy & Space
(Phys.org)—Until recently, the years 774 and 775 were best known for Charlemagne's victory over the Lombards. But earlier this year, a team of scientists in Japan discovered a baffling spike in carbon-14 deposits within the rings of cedar trees that matched those same years. Because cosmic rays are tied to carbon-14 concentrations, scientists around the world have wondered about the cause: a nearby supernova, a gamma ray burst in the Milky Way or an intense superflare emanating from the Sun?