993 Miyake event
Confirmed radiocarbon spike. Red auroras in Korea, Germany, Denmark and Ireland in late 992 and early 993 are the proposed match. The Song dynasty history has no aurora or sunspot at all in 993 to 994, which is itself odd.
How it connects
This mystery we read it in
Hayakawa et al. 2015, Records of sunspot and aurora during CE 960 to 1279 in the Chinese chronicle of the Song dynasty, Earth Planets Space 67:82 no Chinese record 993 to 994
This mystery has this clue
Radiocarbon spike 993 to 994
This mystery has this clue
Korean sky record, late 992
This mystery has this clue
Auroras in Germany, Denmark and Ireland, 992 to 993