Radio occultations of the Io plasma torus by Juno are feasible

TL;DR

This paper proposes using Juno spacecraft radio occultations to measure plasma densities and scale heights in the Io plasma torus, enabling better understanding of plasma flow in Jupiter's magnetosphere.

Contribution

It introduces a novel method to measure plasma densities and spatial variations in the Io plasma torus with high accuracy using radio occultations.

Findings

Plasma column densities can be measured with 10% uncertainty.

Spatial variation scale heights can be determined with similar accuracy.

Method supports system-scale studies of plasma flow in Jupiter's magnetosphere.

Abstract

The flow of material from Io's volcanoes into the Io plasma torus, out into the magnetosphere, and along field lines into Jupiter's upper atmosphere is not adequately understood. The lack of observations of spatial and temporal variations in the Io plasma torus impedes attempts to understand the system as a whole. Here we propose that radio occultations of the Io plasma torus by the Juno spacecraft can measure plasma densities in the Io plasma torus. We find that the line-of-sight column density of plasma in each of the three regions of the Io plasma torus (cold torus, ribbon, and warm torus) can be measured with uncertainties of 10%. We also find that scale heights describing the spatial variation in plasma density in each of these three regions can be measured with similar uncertainties. Such observations will be sufficiently accurate to support system-scale studies of the flow of plasma through the magnetosphere of Jupiter.