This simulation demonstrates a very particular case of the three-body problem and calculates the simple periodic orbit for the newtonian problem of three equal masses in the plane. This is one of the most interesting recently discovered configurations which is caracterized by zero angular momentum and a very rich symmetry pattern. The most surprising feature is that the three bodies chase each other around a fixed eight-shaped curve so that the orbit is stable. By changing the initial conditions we can observe some different instable variations of this motion.
You can change the initial positions (we suppose the only initial zero momentum condition is to be satisfied) just by drag-and-droping the masses. Try, for example, to reset the simulation and and to slightly change the position of one of three bodies.

You can find the original solution proposed by C. Moore in his article "Braids in Classical dynamics" (Physical Review Letters, 1993) and the complete mathematical analysis of this particular case in the article of Alain Chencier and Richard Montgomery "A remarkable periodic solution of the three body problem in the case of equal masses" (Annals of Mathematics, 152 (2000), 881{901).