A large part of humanity has migrated to various planets and space habitats, both in the solar system and around nearby stars such as Barnard's Star and 51 Pegasi.
Queloz performed an analysis on 51 Pegasi using radial velocity measurements (Doppler effect), and was astonished to find a planet with an orbital period of 4.2 days.
Michel Mayor and Didier Queloz discovered the planet orbiting the star 51 Pegasi from observations made using ELODIE on the 1.93 m telescope.
Hot Jupiters - a class of exoplanets like the one around Pegasi 51 (51 Pegasi b)