Illustration of the Swiss astronomer Didier Queloz (born 1966). In 1995, while working for his PhD with advisor Michel Mayor, they discovered the first extrasolar planet orbiting a Sun-like star, 51 Pegasi B. It orbits the star 51 Pegasi, which is 42 light years from Earth. It was discovered using a spectrograph that was able to measure the star's radial (line-of-sight) velocity, which is shifted by the gravitational pull of any orbiting object. Queloz has developed new instruments and methods that have lead to the discovery of hundreds of new exoplanets. Queloz was awarded a share of the Nobel Prize in Physics in 2019, along with Mayor and cosmologist James Peebles, for the discovery of 51 Pegasi B.