Great bands happen when the orbits of bodies in motion intersect and a compatible gravitational pull keeps them together in rotation around a central core of energy, forming a coherent, graceful and dynamic solar system.
Often unconsidered is the fact that even while these planets are circling in concert around one another, each one is still spinning, independently of the motions of the others. Their orbits can remain the same for years or more, synchronized with their cohorts—but the planets still move.
Sometimes, these bodies move farther apart from one another, which can lead to entropy and, eventually, inertia. In other instances, they can move closer to one another; however, when the orbits in these systems become too tight, friction is an inevitable consequence.