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xkcd #2898: Orbital Argument
(imgs.xkcd.com)
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Wait I'm sorry, are we saying that the earth's orbit isn't almost entirely dictated by the gravitational pull of the massive star at the center of our solar system? I am a simple man, I apologize if that is a stupid question.
When dealing with gravitational systems the gravity of each object has to be taken into account. So even though the sun is 99.999% (hyperbole) of the gravity in the equation, the earth’s gravity contributes that small 0.001% and thus the “center” of where they orbit isn’t truly the center of the sun. Tack on Jupiter, which is much more than a fraction of a percent and that “center” moves even farther away from the middle of the sun.
To look at it further, if you had two objects of perfectly equal mass and no other gravitational interference, they would orbit around a point in the middle of each other since their pull is equal. So it’s basically a sliding scale of sorts.
Hope that explains it!
That did help, thanks for taking the time. I think I was thinking about mass and gravity not orbits. Again, I'm an idiot, so that's probably why I missed the central point of the cartoon. 😁