A mole deployed mass spectrometer for sub-surface volatile detection and characterisation at airless bodies

Orbital observational studies and investigations carried out on returned lunar samples have inferred the presence of a significant reservoir of volatile compounds, in particular water. It seems very likely that these volatile compounds will be concentrated at the poles and other locations, such as at depth, where low temperatures exist to provide cryogenic traps. However, the full inventory of these species, their concentration and their sources are unknown To address some of these issues a volatile analysis instrument is required that is specifically designed for identification and quantification of volatiles. The Lunar Volatile Resources Analysis Package is part of the provisional payload for the ESA European Lander and aims to measure the chemical abundance, chemical and isotopic composition of volatiles from regolith samples and the lunar exosphere. It is important to understand, and limit where possible the contamination of the lunar surface by external volatiles in order that measurements are scientifically meaningful. Any controlled soft landing sequence will contaminate the locality of the lander with rocket propellant by-products. Therefore, to allow meaningful scientific return careful considerations must be given to the sampling campaign, i.e. sampling from below or outside of the contamination zone. To this end, it is considered that the use of a sub-surface penetrating mole offers the possibility of accessing material from within the contamination layer and then at increasing depth into pristine sub-surface material. We report on the design and characterisation of an instrumented sub-surface penetrating mole device with an integrated miniaturised ion trap mass spectrometer capable of performing in-situ volatile detection and characterisation at the moon and any other airless body. The design uses the heritage gained from the Ptolemy Mass Spectrometer and the Beagle 2 sub-surface penetrating mole device. We have aimed for a very highly integrated package with technology which is capable of flight readiness within this decade. Major drivers used in instrument design are science capability, and technology elements which include resources (mass, power, volume), maturity (heritage, TRL), ruggedness, contamination, radiation and telemetry and commanding issues.