Comet Ikeya–Zhang (Chinese, Japanese: 池谷-張彗星, officially designated 153P/Ikeya–Zhang) is a comet discovered independently by two astronomers from Japan and China in 2002. On February 1, 2002, Chinese astronomer Zhang Daqing from Kaifeng discovered a new comet in the constellation Cetus, and reported it to the IAU. He found that Japanese astronomer Kaoru Ikeya had discovered it earlier than he had, as the time of sunset is earlier than China. According to tradition, since they discovered the new comet independently, the comet was named after both of them. The comet was initially designated as C/2002 C1 (Ikeya-Zhang).