Kiyotsugu hirayama biography examples

(b. Miyagi prefecture, Japan, 13 October 1874; d. Tokyo, Japan, 8 April 1943)

Celestial mechanics.

Hirayama graduated in 1896 from the University of Tokyo, where he continued his graduate studies in astronomy.

Kiyotsugu hirayama biography examples

He subsequently became an assistant professor and later a full professor at the university and was simultaneously a staff member of the Tokyo Astronomical Observatory.

In 1915 Hirayama went to the United States and studied celestial mechanics under Ernet W.

Brown at Yale and ephemerides at the U. S. Naval Observatory in Washington, D. C. At Brown’s suggestion that a key to the problems of celestial mechanics lies in the movements of the asteroids and satellites, Hirayama worked on an explanation of the condensations and gaps of the distribution of the mean motions of asteroids.

He thought that the condensations were caused by the destruction of a planet. He called a condensation (similar group) a “family” and theorized that each member of a famil