Aurora Poetry

Medieval poets provide key descriptions to track solar events

- Jacek Krywko

Red aurora over Engaru in Hokkaido, Japan

FOR THREE NIGHTS STRAIGHT in the winter of 1204, red and white stripes stretched across the northern and northeastern horizon in the night sky over Kyoto.

This observation was recorded in part by a Japanese noble and poet named Fujiwara Sadaie in his diary, entitled Meigetsuki (The Record of the Clear Moon).

“It was an aurora, and three-day-long auroras are extremely rare,” says Hiroko Miyahara, a physicist at the Okinawa Institute of Science and Technology. To trace the solar events behind these auroras, Miyahara and her colleagues looked for spikes of telltale atomic variations trapped in 13th-century tree rings, using medieval literature to guide their search. Their findings were published in the Proceedings of the Japan Academy, Series B.