Aurora on Triton?

Abstract

It is argued that the presence of an aurora on Triton implies the existence of an intrinsic field on this satellite. The highly conducting ionosphere predicted for Triton, coupled with Triton's 40 km/s velocity relative to the magnetospheric plasma, leads to a limiting current that produces an induced magnetosphere. This magnetosphere would deviate the flowing plasma and reduce the potential across Triton. If Triton were to have a weak intrinsic magnetic field, the current would be funneled into an auroral zone, producing a concentration of current that may trigger specific auroral acceleration processes such as double-layer formation.