Ivan Osipovich Yarkovsky (Polish: Jan Jarkowski) (24 May 1844, Asveya, Vitebsk Governorate – 22 January 1902, Heidelberg) was a Russian civil engineer of Polish descent. He worked for a Russian railway company and was obscure in his own time. Beginning in the 1970s, long after Yarkovsky's death, his work on the effects of thermal radiation on small objects in the solar system (e.g., asteroids) was developed into the Yarkovsky effect and the YORP effect. The asteroid 35334 Yarkovsky is named in his honour †. In 1888 he also created a mechanical explanation of gravitation.