Jupiter’s Pull Makes the Sun Wobble: The Sun–Jupiter Barycentre Lies Just Beyond the Sun’s Surface
Jupiter and the Sun orbit a common centre of mass called the barycentre; at Jupiter’s average distance this barycentre sits about 742,000 km from the Sun’s centre, roughly 46,000 km beyond the Sun’s visible surface, meaning Jupiter does not orbit a fixed Sun but both bodies move around a shifting balance point. This concept helps explain planetary motion and underpins the radial-velocity method used to detect exoplanets by observing stellar wobbles.
