Hiroki Kosai

+ Minor planets discovered: 93 see

was a Japanese astronomer with the Kiso Observatory. He is best known for helping to popularize astronomy in Japan and for his observations of comets and asteroids, most notably with his co-discovery of the comet 1976 XVI. He is credited by the Minor Planet Center (MPC) with the discovery of nearly 100 asteroids.

Kosai died on 26 March 2026, at the age of 93.

Awards and honors Asteroid 3370 Kohsai, discovered by Karl Reinmuth at Heidelberg Observatory in 1930, is named in his honor. The official naming citation was published by the MPC on 14 April 1987 ().

List of discovered minor planets

Hiroki Kosai discovered several asteroids, all in collaboration with Kiichirō Furukawa and Goro Sasaki: 2271 Kiso 22 October 1976 2330 Ontake 18 February 1977 2470 Agematsu 22 October 1976 2924 Mitake-mura 18 February 1977 2960 Ohtaki 18 February 1977 3111 Misuzu 19 February 1977 3249 Musashino 18 February 1977 3291 Dunlap 14 November 1982 3319 Kibi 12 March 1977 3320 Namba 14 November 1982 3391 Sinon 18 February 1977 3392 Setouchi 17 December 1979 3607 Naniwa 18 February 1977 3878 Jyoumon 14 November 1982 4072 Yayoi 30 October 1981 4077 Asuka 13 December 1982 4186 Tamashima 18 February 1977 4272 Entsuji 12 March 1977 4526 Konko 22 May 1982 4812 Hakuhou 18 February 1977 4855 Tenpyou 14 November 1982 4890 Shikanosima 14 November 1982 4929 Yamatai 13 December 1982 4963 Kanroku 18 February 1977 5017 Tenchi 18 February 1977 5018 Tenmu 19 February 1977 5082 Nihonsyoki 18 February 1977 5454 Kojiki 12 March 1977 5466 Makibi 30 November 1986 5541 Seimei 22 October 1976 6031 Ryokan 26 January 1982 6218 Mizushima 12 March 1977 6818 Sessyu 11 March 1983 6846 Kansazan 22 October 1976 7104 Manyousyu 18 February 1977 7105 Yousyozan 18 February 1977 7562 Kagiroino-Oka 30 November 1986 7627 Wakenokiyomaro 18 February 1977 7634 Shizutani-Kou 14 November 1982 7991 Kaguyahime 30 October 1981 8133 Takanochoei 18 February 1977 8144 Hiragagennai 14 November 1982 9147 Kourakuen 18 February 1977 9153 Chikurinji 30 October 1981 9293 Kamogata 13 December 1982 9719 Yakage 18 February 1977 10006 Sessai 22 October 1976 10008 Raisanyo 18 February 1977 10009 Hirosetanso 12 March 1977 10453 Banzan 18 February 1977 11254 Konkohekisui 18 February 1977 11255 Fujiiekio 18 February 1977 11442 Seijin-Sanso 22 October 1976 11827 Wasyuzan 14 November 1982 12186 Mitukurigen 12 March 1977 12221 Ogatakoan 14 November 1982 12682 Kawada 14 November 1982 14313 Dodaira 22 October 1976 14314 Tokigawa 18 February 1977 14315 Ogawamachi 12 March 1977 14316 Higashichichibu 12 March 1977 14338 Shibakoukan 14 November 1982 14795 Syoyou 12 March 1977 14820 Aizuyaichi 14 November 1982 14821 Motaeno 14 November 1982 15202 Yamada-Houkoku 12 March 1977 15671 Suzannedébarbat 12 March 1977 15672 Sato-Norio 12 March 1977 16357 Risanpei 22 October 1976 18289 Yokoyamakoichi 22 October 1976 18290 Sumiyoshi 18 February 1977 18291 Wani 18 February 1977 18322 Korokan 14 November 1982 19083 Mizuki 18 February 1977 12 March 1977 19953 Takeo 14 November 1982 19954 Shigeyoshi 14 November 1982 20962 Michizane 12 March 1977 22277 Hirado 14 November 1982 24640 Omiwa 13 December 1982 26794 Yukioniimi 18 February 1977 26806 Kushiike 22 May 1982 14 November 1982 34995 Dainihonshi 18 February 1977 34996 Mitokoumon 18 February 1977 12 March 1977 14 November 1982 14 November 1982 52260 Ureshino 22 May 1982 52261 Izumishikibu 14 November 1982 12 March 1977 12 March 1977 30 November 1986 Co-discovery made with: K. Furukawa G. Sasaki

Hiroki Kosai

Bron en licentie