Koichi Yokoyama (b. 1940) is a professor emeritus of the National Astronomical observatory, Japan. He was Director of the International Polar Motion Service (1981-1987) and first chairman of the directing board of the International Earth Rotation Service. He also improved the nutation tables.
Avastatud: 22-10-1976 Avastamiskoht: Kiso Avastajad: Kosai, H., Hurukawa, K.