Keplorr is a planet which is constantly being orbited by Galileans.
While Keplorr is universally known as the homeworld of the Galileans, no Galilean has actually ever set foot on his own home planet. The closest they ever come is residing for a time in orbit around it, revolving like electrons around an atomic nucleus, held in pattern by their planet's gravitational pull.
The more Galileans in orbit around Keplorr at any given time, the greater the energy of the entire system. When the amount of this energy builds up to a critical point, the Galileans are flung away from Keplorr and into the far reaches of space. But like salmon swimming upstream, Galileans are instinctually drawn back to their home planet every so often to re-energize.
The name Keplorr is play on Johannes Kepler, who described planetary motion via a set of laws.