A long-period comet, discovered independently on 1965 September 18 by the Japanese amateur astronomers Kaoru Ikeya (1943– ) and Tsutomu Seki (1930– ); formerly designated 1965 VIII. It is a member of the Kreutz sungrazer group. Perihelion, 0.008 AU (1.2 million km), was on 1965 October 21, when its nucleus broke into three fragments. At perihelion the comet reached at least magnitude −10 and could be seen in broad daylight, while its tail reached about 60° in late October. Ikeya–Seki's orbit has a period of about 880 years, eccentricity 0.9999, and inclination 141°.9.
http://cometography.com/lcomets/1965s1.html Information page at Cometography website.
Subjects: Astronomy and Astrophysics.