MMX-Rover: A small Rover for big firsts

Abstract

MMX (Martian Moons eXploration) is a JAXA mission which aims to study the two moons of Mars, Phobos and Deimos. In addition to extensive in-situ scientific observation, the MMX probe is equipped to bring samples back from Phobos to Earth, and to deploy the CNES/DLR rover IDEFIX, onto its surface. IDEFIX mission is to investigate the Phobos surface properties, to secure the landing of the MMX probe itself and for scientific purposes. Another mission objective is to test some technological concepts, such as the use of CubeSat technology in the context of space exploration, the way to move in low gravity, and auto-navigation. To fulfil its mission, IDEFIX brings four scientific instruments: miniRad (Radiometer), RAX (Raman spectrometer), a pair of (stereo) navigation cameras, and two wheelcameras. IDEFIX will be operated by two remote control centers, one in France and one in Germany, in close cooperation with the JAXA MMX ground segment. The MMX mission will be launched in autumn 2026, and the landing of IDEFIX is presently scheduled for end of 2028/beginning 2029, after a first Phobos observation campaign by MMX probe and the selection of a landing site. IDEFIX operations on Phobos surface shall last at least 100 days. IDEFIX mission will be the occasion of several firsts: - First landing on Phobos, - First French and German rover, - First rover aiming at driving, and experimenting auto-navigation, on a low gravity body, - First dynamic analyzes of regolith at low gravity, thanks to its interaction with the wheels. This paper will introduce the MMX rover mission objectives, the rover design, overall system composition and mission profile, with the outlines and principal constraints of the three main mission phases (Cruise, Landing, and Phobos Exploration). It will provide as well an overview of the mission calendar and main milestones.