Chapter 5
Astronomy in Early Showa. III. Sendai
1926–1945
Abstract Sendai is a central city of the northeastern region of Japan’s main island,
and it was a capital of the Sendai clan, which continued from the early Tokugawa
until the Meiji Revolution. In 1907 Tohoku Imperial University was established in
Sendai as a new type of university opened for women and foreign students. Astronomy was promoted at first by physicists Kusakabe Shirota and Ishiwara Jun, then
taken over by astrophysicists Matukuma Takehiko and Hitotuhanagi Zyuiti
(Takeuchi and Seki 2008; Takeuchi 2014).
5.1 Early History of Astronomy
5.1.1 Sendai in the Tokugawa-Meiji Period
Around 1670, the Sendai clan sent Eshi Tomotatsu (江志知辰, 1649–1714) to
Kyoto to study astrology and calendar making under Shibukawa Harumi
(Chap. 1). In Sendai, Eshi’s disciples, Aoki Nagayoshi (青木長由, 1669–1740)
and Toita Yasusuke (戸板保祐, 1708–1784), worked at the Tenmonkata (天文方,
Bureau of Astronomy) of the clan and built a base of astronomy in Sendai. Toita
constructed an armillary sphere in 1733 and began to make accurate time observations of celestial phenomena, including solar eclipses, comets, and stellar motions.
Whereas the purpose of his observations was high-precision calendar making, he
also paid attention to peculiar phenomena, such as comets, meteors, parhelion,
planetary motions, and others. In his book Iseishō (Digest of Peculiar Stars, 異星
鈔, 1759), Toita described numerous particular phenomena with an astrological
interpretation, such as what type of disaster might happen in the near future given
a particular sky event.
In the middle of the nineteenth century, Furuyama Makoto (古山誠, or Furuyama
Toshisada, 古山利貞, 1824–1887) began to work on astronomy and geodesy in
Sendai (Takeuchi 2014). Furuyama was born in Sendai as a samurai of the Sendai
clan. From his youth he studied mathematics, astronomy, and geodesy in Western
style, as well as classical Shintoism. He was hired as an assistant astronomer in 1840
and then promoted as a Tenmonkata of the clan in 1855. His work was the annual
© Springer Nature Switzerland AG 2021
T. Kogure, The History of Modern Astronomy in Japan, Historical & Cultural
Astronomy, https://doi.org/10.1007/978-3-030-57061-3_5
119
Astronomy in Early Showa. III. Sendai
1926–1945
Abstract Sendai is a central city of the northeastern region of Japan’s main island,
and it was a capital of the Sendai clan, which continued from the early Tokugawa
until the Meiji Revolution. In 1907 Tohoku Imperial University was established in
Sendai as a new type of university opened for women and foreign students. Astronomy was promoted at first by physicists Kusakabe Shirota and Ishiwara Jun, then
taken over by astrophysicists Matukuma Takehiko and Hitotuhanagi Zyuiti
(Takeuchi and Seki 2008; Takeuchi 2014).
5.1 Early History of Astronomy
5.1.1 Sendai in the Tokugawa-Meiji Period
Around 1670, the Sendai clan sent Eshi Tomotatsu (江志知辰, 1649–1714) to
Kyoto to study astrology and calendar making under Shibukawa Harumi
(Chap. 1). In Sendai, Eshi’s disciples, Aoki Nagayoshi (青木長由, 1669–1740)
and Toita Yasusuke (戸板保祐, 1708–1784), worked at the Tenmonkata (天文方,
Bureau of Astronomy) of the clan and built a base of astronomy in Sendai. Toita
constructed an armillary sphere in 1733 and began to make accurate time observations of celestial phenomena, including solar eclipses, comets, and stellar motions.
Whereas the purpose of his observations was high-precision calendar making, he
also paid attention to peculiar phenomena, such as comets, meteors, parhelion,
planetary motions, and others. In his book Iseishō (Digest of Peculiar Stars, 異星
鈔, 1759), Toita described numerous particular phenomena with an astrological
interpretation, such as what type of disaster might happen in the near future given
a particular sky event.
In the middle of the nineteenth century, Furuyama Makoto (古山誠, or Furuyama
Toshisada, 古山利貞, 1824–1887) began to work on astronomy and geodesy in
Sendai (Takeuchi 2014). Furuyama was born in Sendai as a samurai of the Sendai
clan. From his youth he studied mathematics, astronomy, and geodesy in Western
style, as well as classical Shintoism. He was hired as an assistant astronomer in 1840
and then promoted as a Tenmonkata of the clan in 1855. His work was the annual
© Springer Nature Switzerland AG 2021
T. Kogure, The History of Modern Astronomy in Japan, Historical & Cultural
Astronomy, https://doi.org/10.1007/978-3-030-57061-3_5
119