Mayor and Queloz Discovered 51 Pegasi b in 1995, Launching a 5,500-Planet Exoplanet Era
Updated
Updated · Daily Kos · Aug 10
Mayor and Queloz Discovered 51 Pegasi b in 1995, Launching a 5,500-Planet Exoplanet Era
1 articles · Updated · Daily Kos · Aug 10
Summary
In October 1995, Swiss astronomers Michel Mayor and Didier Queloz detected 51 Pegasi b around a Sun-like star 50 light-years away, a finding widely seen as the breakthrough that opened modern exoplanet science.
Using the ELODIE spectrograph at France’s Haute-Provence Observatory, they measured tiny Doppler shifts in the star’s motion — the radial-velocity “wobble” caused by an orbiting planet.
51 Pegasi b upended theory: the gas giant, at least half Jupiter’s mass, circles its star every 4.2 days from just 8 million kilometers away, defining the then-unexpected class of “hot Jupiters.”
More than 5,500 exoplanets have since been confirmed as transit, microlensing, direct-imaging and astrometry methods expanded the search beyond the original radial-velocity technique.
The discovery earned Mayor and Queloz the 2019 Nobel Prize in Physics and underpins today’s push to study exoplanet atmospheres and hunt for possible biosignatures with telescopes such as James Webb.