In a binary star system, could a planet travel in an 8 shape around both?

Question

Is it possible for a planet to have an orbit that goes around both stars? In an 8 shape specifically, wherein when it goes through the space between the stars, it changes it's direction and goes around the opposite star to which it just left?

Answer 1

This is the classic three-body problem in physics, and it's not analytically solvable in the general case. Most solutions are chaotic, but some particular ones have curious orbital paths. Unfortunately, for a binary star system where the planet's mass is neglible, there doesn't seem to be a stable figure-8 orbit about them. You can check out this interesting website that explores different three-body orbits, link below. The difficulty of achieving a stable figure-8 orbit stems from the fact the binary star system is itself in motion.

Answer 2

The answer may not be known because it may be possible to to tweak the masses, separations and initial conditions so that such an orbit could be created. Still, I think such orbits don't exist in nature or are at least unstable because when you have three bodies strongly gravitationally interacting, the least massive member almost always gets ejected from the system or gets put in a very elliptical orbit. One can have a situation where a planet may be captured by one star from another making a close appoach. This last point was the topic of a recent journal paper by Fred Adams and Greg Laughlin.

Answer 3

There are a number of variables to consider with this, proximity to the stars, the size and spectral type of both stars, what type of planet it is you are referring to, but I suppose if you mean one like the Earth, my guess is that it would be torn apart from gravitational forces with an orbit like you are suggesting.
Again as I said, it depends on a number of variable factors.