Michel Gustave Édouard Mayor (born 12 January 1942) is a Swiss astrophysicist. He was professor emeritus at the University of Geneva's Department of Astronomy. He retired in 2007, but works as a researcher at the Observatory of Geneva. He is co-winner of the 2019 Nobel Prize in Physics, the 2010 Viktor Ambartsumian International Prize, and the winner of the 2015 Kyoto Prize.