Saturn's ringlets

This paper suggests that Saturn's magnetic field is, in part, responsible for the very fine-scale radial features, or ringlets, seen in the ring-system. The planet's dipole field interacts with slight radial variations in plasma density, and the operation of an instability segregates the magnetic flux and plasma in the ring-plane into narrow alternating zones. It is suggested that this mechanism may act by itself to give rise to the inner ringlets. It is believed that at greater radial distances it amplifies gravitational resonances.