Didier Queloz

Queloz, together with Michel Mayor, discovered 51 Pegasi b in 1995, the first exoplanet found orbiting a Sun-like star. The planet is a gas giant roughly half the mass of Jupiter but orbits its star in just over four days, making it a 'hot Jupiter.'

Queloz shared the 2019 Nobel Prize in Physics with Michel Mayor and James Peebles. Mayor and Queloz were honored specifically for the discovery of 51 Pegasi b, which opened the modern era of exoplanet research.

Queloz holds joint positions at the University of Cambridge and the University of Geneva. His research group at Cambridge focuses on detecting and characterizing Earth-like exoplanets around nearby stars.

They used the radial velocity method—measuring tiny periodic shifts in the star's spectral lines caused by the gravitational pull of an orbiting planet. The observations were made using the ELODIE spectrograph at the Observatoire de Haute-Provence in France.