There are no generalized solutions to the three-body problem. Say you have three planets orbiting each other: it’s impossible to calculate how they will move using Newton’s laws of motion and gravity.

Unlike the two-body problem, the three-body problem has no general closed-form analytic solution. The differential equations that govern the motions of three gravitating bodies are not integrable and cannot be solved to give explicit formulas for the positions of the bodies as a function of time. For most initial conditions, the dynamical system for three orbiting bodies is chaotic, and the only way to predict their motions is to estimate them using numerical methods.

But thousands of stable three-body orbits have been found — their paths repeat after a given interval. The Three Body Orbits website is an atlas of some of those orbits: you can watch each three-body system play itself out in a wide variety of different shapes and complexities. There’s this simple figure 8, this slightly less simple one, and this one that looks like a spirograph.

Underlying Source: https://www.threebodyorbits.com/

  • ns1@feddit.uk
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    3 days ago

    This makes me wonder if any of the fancy orbits can be found in nature, or if it’s always the usual star/planet/moon configuration

    • manxu@piefed.social
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      3 days ago

      There are plenty triple and quadruple star systems that manage to survive. If two stars in such a system are closer to each other than to the rest, then they essentially form a single binary that is independent of the other bodies. Alpha Centauri comes to mind, the nearest star system to us. A and B are close to each other, and Proxima, the third one in the system and closest star to the sun, essentially rotates around the first pair.

    • Creat@discuss.tchncs.de
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      3 days ago

      Planets of larger size (at least in our solar system) have multiple or many moons.

      Things tend to be unstable in reality rather easily, and since star systems are around for billions of years, them being in that configuration are slim once observed.