Zhang Yuzhe

Zhang Yuzhe, also known as Yu-Che Chang, was a Chinese astronomer and director of the Purple Mountain Observatory who is widely regarded as the father of modern Chinese astronomy. He studied the light curves of asteroids, and thus their rotation periods. He also researched the variable star CZ Cassiopeiae and the evolution of the orbit of Comet Halley. Zhang discovered three comets and is credited under the name Y. C. Chang by the Minor Planet Center for the discovery of one minor planet, the outer main-belt asteroid 3789 Zhongguo.