Named in honor of Yasuo Tanaka (1931– ), Japanese astrophysicist, who organized the first group of space scientists in the Netherlands. Tanaka is head of the space research group in Japan. He contributed to the launching of the Japanese satellites Hakucho (1979), Tenma (1983) and Ginga (1987). Ginga observed the first X-ray signals from supernova 1987A. (M 18142) _ _.