Fundación Galileo Galilei - INAF Telescopio Nazionale Galileo 28°45'14.4N 17°53'20.6W 2387.2m A.S.L.

Nobel Prize for Physics 2019: James Peebles, Michel Mayor, Didier Queloz

The Nobel Prize for Physics 2019 was awarded to James Peebles for his discoveries in the field of cosmology; Michel Mayor and Didier Queloz for the discovery of the first exoplanet in orbit around a solar-type star, 51 Pegasi.

M. Mayor, Professor at the University of Geneva, and D. Queloz, Professor at the University of Cambridge (United Kingdom), discovered, in 1995, the first planet orbiting a star outside our Solar System: 51 Pegasi b. The exoplanet located at a distance of 50 light years from Earth, orbits around its star in only 4 days. Due the proximity of the planet to the star,its surface has a temperature of about 1000 degrees Celsius, which makes it a no-habitable planet.

Mayor and Queloz discovered the first exoplanet using the Doppler effect. We can measure the radial velocity variations of the star due to the gravitational force of a planet orbiting around it. Such measurements are performed with instruments named spectrographs, like HARPS-N (High Accuracy Radial velocity Planet Searcher in North hemisphere), installed at the Telescopio Nazionale Galileo since 2012.

To date, astronomers have discovered more than 4000 exoplanets, a lot of them using HARPS-N. The whole TNG staff is proud that Michel Mayor was one of the main promoters of HARPS-N and is still one of the main users.

Useful link:

Symbolic fiber cut at the inauguration

Symbolic fiber cut at the inauguration by M. Mayor and D. Latham (April 23 of 2012)
Credits: J. San Juan (FGG-INAF)


HARPS-N: the hunter of exoplanet at the TNG.
Credits: A. Harutyunyan (FGG-INAF)