Michel Gustave Édouard Mayor (French pronunciation: [miʃɛl majɔʁ]; born 12 January 1942)[2] is a Swiss astrophysicist and professor emeritus at the University of Geneva's Department of Astronomy.

[6] For this achievement, they were awarded the 2019 Nobel Prize in Physics "for the discovery of an exoplanet orbiting a solar-type star"[7] resulting in "contributions to our understanding of the evolution of the universe and Earth’s place in the cosmos".

Subsequently, he spent sabbatical semesters at the European Southern Observatory (ESO) in northern Chile and at the Institute for Astronomy of the University of Hawaiʻi System.

[12] Mayor's research interests include extrasolar planets (also known as exoplanets), instrumentation, statistical properties of double stars, globular cluster dynamics, galactic structure and kinematics.

[2] During his time as a research associate, there had been strong interest in developing photoelectric-based Doppler spectrometers to obtain more accurate measurements of radial velocities of stellar objects compared to existing photographic methods.

ELODIE was developed with the specific intent to determine if the substellar secondary objects were brown dwarf stars or potentially giant planets.

[15] By 1994, ELODIE was operational at Geneva and Mayor and Queloz began their survey of Sun-like systems with suspected substellar secondary objects.

[25] In collaboration with Pierre-Yves Frei, Mayor wrote a book in French called Les Nouveaux mondes du Cosmos (Seuil, 260 pages), which was awarded the Livre de l'astronomie 2001 prize by the 17th Astronomy Festival Haute Maurienne.

[25] Mayor has received the 2011 BBVA Foundation Frontiers of Knowledge Award of Basic Sciences (together with his former student Didier Queloz) for developing new astronomical instruments and experimental techniques that led to the first observation of planets around Sun-like stars.

[26] Asteroid 125076 Michelmayor, discovered by Swiss amateur astronomer Michel Ory at the Jura Observatory in 2001, was named in his honor.