Space Fact Of The Day: Jupiter Doesn’t Orbit The Sun
Crazy right? That’s how enormous Jupiter is. It’s 2.5 times the mass of all the other planets in the Solar System combined. This means it’s actually big enough to offset the center of gravity between it and the Sun. Instead of being in the centre of the Sun, it’s a point in space above the Sun’s surface.
This is how that works.
When you think of a small object orbiting a larger object in space, you think of it as the smaller spinning perfect circles around the bigger. In reality, both objects orbit a combined center, just off of the larger object. Take Earth orbiting the Sun as an example. Given how much larger the Sun is compared to Earth, the center of gravity is very close to the center of the Sun, so the phenomenon has very little effect on the orbit. It’s the same with all the other planets in the Solar System, bar Jupiter.
With that gas giant, the center of mass with the sun (the barycenter) is about 7% of a sun-radius above the surface of the Sun. Jupiter and the Sun both orbit that point. Here’s a GIF from NASA that shows the effect (not to scale):
That’s basically how Jupiter and the Sun interact in space. Just remember this animation is only showing the effect, not the scale of the sizes and distances as is factually correct. The Sun is still far more vast than Jupiter, with a diameter of 1,392,000km. This is 9 times the diameter of Jupiter (142,800km), which, in itself, is 11.2 times the diameter of Earth (12,756km). In summary, things in space are pretty damn big.
Just to blow your mind even more, here’s a video showing the size things in our Solar System as compared to some other stars out there:
There. Now you have not just one, but about three awesome space facts for the staff Christmas party.