Japanese researchers look at 800-year-old books and trees for signs of extreme solar events

On Feb. 21, 1204, Japanese poet Fujiwara no Teika described in his diary a bizarre phenomenon: the northern Kyoto skies suddenly burning red at night.

by By Tomoko Otake

https://www.japantimes.co.jp/news/2026/04/10/japan/science-health/fujiwara-no-teika-diary-solar-storms/

Full article here:
https://www.jstage.jst.go.jp/article/pjab/102/4/102_pjab.102.011/_article

Solar cycle at PG:
https://www.gutenberg.org/ebooks/search/?query=solar+cycle

#books #old_manuscripts #medieval_solar_activity