If we picture the solar system, we often picture our dominant star at the center of things, static and immobile as planets orbit circles around it. That picture makes things simple to understand, but technically it’s inaccurate. Take our largest planet Jupiter, for instance. It doesn’t orbit the sun’s center — it orbits a spot in empty space between it and the sun called the barycenter. This is because the sun doesn’t just exert gravity on Jupiter — Jupiter’s so big that its own pull affects how the sun moves, too.
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