Speaker
Description
.The origin of the moons of Mars, Phobos and Deimos, has long been debated. The two leading theories are that they are either captured asteroids or the result of ejected material from a giant impactor. The upcoming JAXA mission Mars Moons eXplorer (MMX) aims to clarify key unknowns regarding the composition, minerology and surface structure, and thus help to unravel the mystery of the origin of the moons. Launching in 2026, MMX will investigate the properties of both moons through orbital observations and rover surface operations on Phobos, which will also return surface samples from Phobos.
A variety of European instruments have been incorporated into the mission, notably the French-built MIRS (MMX Infra-Red Spectrometer) instrument contained on the orbiter, and the CNES-DLR rover Idefix. In order to enable effective testing and calibration of these two instruments, numerous simulants of Phobos’ surface have been created. However, significant gaps remain in the properties represented.
In this project, we aim to create simulants which target key deficits in the existing materials, thus enabling more specialised tests to be run. For Idefix, we are producing a physical properties simulant which represents the albedo and particle size distribution of the regolith, as these properties are necessary for further testing of the onboard cameras. For MIRS we aim to produce a simulant with a similar spectral profile to Phobos which is also mineralogically representative, as this is a significant gap within the spectral libraries. The simulant recipes will be designed through comparison of the compositional, mechanical and spectral properties of analogue materials to Phobos’ regolith (using available orbital data) and the selection of the closest matches for each feature. Production, characterisation and further testing will take place in the Vulcan Facility, before communication of the results to the appropriate MMX instrument teams.
We hope that through this work we can help with supporting and de-risking MMX, while also contributing to the advancement of Phobos surface research, and to the broader simulant design and production process from a geological perspective.
