An Impacting Descent Probe for Europa and the other Galilean Moons of Jupiter

TL;DR

This paper proposes a small impact descent probe for Europa and other Galilean moons, enhancing scientific data collection during planetary encounters with minimal added complexity and risk.

Contribution

It introduces a novel impact descent probe concept that can be deployed by orbiters to increase scientific return from planetary bodies without significant additional engineering effort.

Findings

Design of a small (<100 kg) impact descent probe for Europa.

Potential to collect surface images, exosphere data, and magnetic field measurements during descent.

Extension of previous concepts with detailed assessment for NASA's Europa mission.

Abstract

We present a study of an impacting descent probe that increases the science return of spacecraft orbiting or passing an atmosphere-less planetary body of the solar system, such as the Galilean moons of Jupiter. The descent probe is a carry-on small spacecraft (< 100 kg), to be deployed by the mother spacecraft, that brings itself onto a collisional trajectory with the targeted planetary body in a simple manner. A possible science payload includes instruments for surface imaging, characterisation of the neutral exosphere, and magnetic field and plasma measurement near the target body down to very low-altitudes (~1 km), during the probe's fast (~km/s) descent to the surface until impact. The science goals and the concept of operation are discussed with particular reference to Europa, including options for flying through water plumes and after-impact retrieval of very-low altitude science data. All in all, it is demonstrated how the descent probe has the potential to provide a high science return to a mission at a low extra level of complexity, engineering effort, and risk. This study builds upon earlier studies for a Callisto Descent Probe (CDP) for the former Europa-Jupiter System Mission (EJSM) of ESA and NASA, and extends them with a detailed assessment of a descent probe designed to be an additional science payload for the NASA Europa Mission.