By combining written texts, folklore, and astronomical calculations, a team of researchers at Nagoya University, the National Astronomical Observatory of Japan, and Otaru University of Commerce identified, examined, and analyzed specific records for three historical eclipses. The texts included the writings of Tokunai Mogami (1755–1836), one of the most prominent Shogunate explorers for Hokkaido, Sakhalin, and the Kuril Islands, the islands found between Japan and Russia.