PINPOINTING the stable ways in which three planets or stars can waltz around each other has long been a perplexing problem. Now two mathematicians have proved the possibility of a new dance, in which the stars chase each other around a figure of eight.
Newton’s equations of motion can easily be solved to describe exactly how two bodies orbit each other. But if you throw in a third mass, the picture becomes hugely complex and it’s impossible to calculate all the possible periodic orbits directly.
51¶¯Âþs in the 16th and 17th centuries found some simple solutions. For instance, Swiss mathematician…
