After nearly eight years of travel, BepiColombo has just reached a major milestone : on 3 September 2026, the Mercury Transfer Module (MTM) successfully separated from the two scientific orbiters, ESA’s Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (Mio). Equipped with solar-powered electric motors, the MTM has carried the probes over billions of kilometres and completed nine planetary flybys, including six of Mercury. Its transport mission ends here, but this separation does not mark BepiColombo’s arrival at the planet : it marks the beginning of its mission.
The two orbiters are now continuing their journey together towards Mercury before separating in turn and each entering their dedicated scientific orbit to study the planet from complementary perspectives.
LIRA plays a central role in this mission with two instruments : SORBET, a high-frequency radio receiver on board Mio, which will study Mercury’s magnetosphere and its interaction with the solar wind using radio frequencies for the first time ; and VIHI, a spectro-imager on board MPO, which will produce a comprehensive mineralogical map of the planet’s surface to shed light on its geological history.
