TIL ; That Jupiter doesn't revolve around the Sun

warrensteem(65)

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We've always been told that every planet in our solar system revolves around the sun

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Well this is actually in correct. Ill try break it down to make it as simple as possible.

When a small object orbits a large object, they actually orbit their center of gravity.
So for instance when the earth orbits the sun, the center of gravity between these two lie pretty much at the center of the sun because of the massive mass the sun has. Therefor making it seem like the earth it self is orbiting the sun which in fact it orbits their center of gravity.

Another Example is the ISS ( International Space Station ) and the earth. Due to the difference is mass between the ISS and the earth, their center of gravity is nearly perfectly in the center of the earth and therefor creates a perfect orbit around earth.

This is were the term barycenter comes in

What is a barycenter?

Well taken directly from wikipedia it states that

is the center of mass of two or more bodies that are orbiting each other, or the point around which they both orbit. It is an important concept in fields such as astronomy and astrophysics. The distance from a body's center of mass to the barycenter can be calculated as a simple two-body problem.
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So now this leads us to Jupiter

Jupiters' mass is so great that it has 2.5 times the mass of all the other planets in the entire solar system combined. This means that the center of gravity of the these two giants(Jupiter and the Sun) is actually 1.07 solar radii from the center of the sun, so its 7% of the suns radius away from the surface.

Below is a gif to further explain this ( This is not to scale)

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