After a journey of almost eight years (it began with its launch on 20 October 2018), BepiColombo has reached another crucial milestone: on 3 September 2026, the Mercury Transfer Module (MTM), which carried the mission from Earth to Mercury, was successfully separated.
Equipped with solar-electric propulsion engines and solar panels, the MTM provided the power and thrust required throughout the long interplanetary journey, which included several flybys of Earth, Venus and Mercury. Having completed its task, the module was separated from the two scientific orbiters, which will now proceed towards their respective operational orbits.
The ESA-JAXA’s mission is now entering its final phase, hereunder the “agenda”:
🛰️ 21 November 2026 – Mercury Orbit Insertion (MOI)
The two scientific orbiters, ESA’s Mercury Planetary Orbiter (MPO) and JAXA’s Mercury Magnetospheric Orbiter Mio, still joined together, will enter orbit around Mercury.
🛰️ 9–10 December 2026 – Separation of the orbiters
MPO and Mio will separate and move into their respective dedicated orbits.
December 2026–March 2027 – Commissioning
The scientific instruments aboard the two spacecraft will undergo final testing, configuration and calibration.
🛰️ April 2027 – Start of scientific operations
The spacecraft will begin the systematic collection of data on Mercury’s surface, composition and magnetosphere.
OHB Italia S.p.A. is proud to contribute to this remarkable mission through the SERENA instrument, developed together with INAF Istituto Nazionale di Astrofisica and Agenzia Spaziale Italiana. SERENA (Search for Exosphere Refilling and Emitted Neutral Abundances) is a suite of four sensors designed to investigate the interaction between Mercury’s surface and its surrounding space environment. By measuring neutral and ionised particles around the planet, it will help scientists better understand Mercury’s exosphere and the complex processes that govern the release, transport and escape of particles between the surface, the exosphere and the magnetosphere.
The separation of MTM is a decisive step for one of the most complex interplanetary missions ever developed and the beginning of a new phase in the study of the planet closest to the Sun.
Image credits: ESA/ATG medialab.
