Radial Velocity

摘要

Radial velocity measurement is the mother of exoplanet search techniques. Michel Mayor and Didier Queloz of the Observatory of Geneva in Switzerland used it in 1995 to make the first confirmed detection of an exoplanet around a sunlike star, and it's still going strong. As a planet orbits a star, its gravity causes the star to move around their common center of gravity, usually inside the star. If we view such a system edge-on, the star would appear to be wobbling from side to side. Current telescopes can't detect such tiny movements, but they can spot a wobble back and forth along the line of sight because such changes in radial velocity raise and lower the frequency of the star's light.