Jupiter is the fifth planet from the sun and is known for being absolutely huge. In fact, the gas giant is so large, it actually doesn’t orbit the sun.
With 2.5 times the mass of all of the other planets in the solar system combined—it’s big enough that the center of gravity between Jupiter and the sun doesn’t actually reside inside the sun. Instead, it sits at a point in space just above the sun’s surface.
Here’s the short of it: when a small object orbits a big object in space, the less massive one doesn’t travel in a perfect circle around the large one. Instead, both objects orbit a combined center of gravity.
When it comes to the Earth orbiting the sun, the center of gravity is so close to the center of the larger object that the impact of this phenomenon is too small to be noticeable. The bigger object doesn’t seem to move, and the smaller one draws a circle around it, Business Insider reports.
When the International Space Station (ISS) orbits the Earth, both the Earth and the space station orbit their combined center of gravity, but the center of gravity is so close to the center of the Earth that the planet’s motion around the point is difficult to spot. The ISS has a near-perfect circle around the whole planet. The same is true when most planets orbit the Sun. It is so much larger than planets like Earth of Venus, that their centers of mass with the sun all lie within the star itself.
With Jupiter, it’s a different story. The gas giant is so big that its center of mass with the sun actually exists 1.07 solar radii from the middle of the sun. Both the Sun and Jupiter orbit around that point in space. Essentially, Jupiter and the sun move through space together—though the distances and sizes are different.
Internal structure of jupiter