Jupiter 318 times more massive than Earth. As a result of its large mass, the barycenter of Jupiter and the Sun isn't near the center of the Sun – it's just outside the Sun's surface.
The barycenter is the center of mass of a system of objects moving under the influence of their mutual gravity. In a system of bodies with identical masses, the barycenter lies directly in the center of the two bodies. For the Earth-Moon system, the barycenter is lies 1,710 kilometers below Earth's surface. This is because Earth is far more massive than the Moon and it is this common center of mass around which Earth and the Moon seem to go around.
|As seen from above, a large planet and a star orbit their shared center of mass, or barycenter.|
|As seen from the side, a large planet and a star orbit their shared center of mass, or barycenter. The slightly off-center barycenter is what makes the star appear to wobble back and forth.|