The 993–994 AD Miyake Event

What happened

The second confirmed solar superstorm identified by Fusa Miyake's tree-ring team, published in 2013 — a rapid 9.1% radiocarbon spike dated to AD 993–994, about 220 years after the 774–775 AD event and roughly 0.6 times its size. Confirmed independently across multiple tree-ring records worldwide, it remains one of only a handful of such ancient superstorms identified to date, all inferred from isotope spikes rather than direct observation.