# BepiColombo hands power and propulsion to its science orbiter Canonical URL: https://www.theroboteconomy.news/articles/bepicolombo-cruise-module-operational-handover/ Publisher: The Robot Economy Editorial byline: Mara Voss, Deployment Desk Published: 2026-09-10T08:13:40.355Z Updated: 2026-09-10T08:13:40.355Z Editorial information: https://www.theroboteconomy.news/about/#editorial-desks The cruise module has separated, but Mercury orbit is still ahead. The remaining spacecraft must complete a staged approach before full science operations in April 2027. ## Summary BepiColombo separated its Mercury Transfer Module on 3 September 2026. ESA's subsequent operational account and a September 8 instrument-team update distinguish that success from arrival in orbit. The Mercury Planetary Orbiter now powers the remaining stack and supplies chemical propulsion for the approach. Orbit insertion is planned for November 21, orbiter separation in December, and full science operations in April 2027. ## Key facts - ESA confirmed cruise-module separation on 3 September 2026. - The Mercury Planetary Orbiter's solar panels are charging the remaining spacecraft stack. - Mercury orbit insertion is planned for 21 November 2026, not already completed. - The European and Japanese science orbiters are scheduled to separate on 9-10 December 2026. - Full science operations are planned for April 2027. ## Lead image Image: https://www.theroboteconomy.news/images/articles/bepicolombo-cruise-module-operational-handover.webp Description: BepiColombo operators at consoles in ESA's Darmstadt control room during the Mercury Transfer Module separation operation on 3 September 2026. Credit: BepiColombo separation operations, Darmstadt, 3 September 2026. Photo: ©ESA; cropped and exposure adjusted. ## Report BepiColombo's European science orbiter has taken over power and propulsion for the next stage of its journey to Mercury. The European-Japanese robotic mission released its Mercury Transfer Module on September 3. ESA's September 7 operational account and a September 8 update from instrument laboratory LIRA set out what follows: two science orbiters travelling together, then a sequence of manoeuvres into different working orbits. Sources: [s1]() [s2]() ### A new power and propulsion configuration ESA's operational log says the Mercury Planetary Orbiter's solar panels are charging the spacecraft batteries and that it will power the stack until Japan's Mio orbiter separates. The remaining approach will use the European orbiter's chemical propulsion system. That changes the propulsion regime: the cruise system expelled electrically accelerated xenon ions for sustained low thrust, while chemical propulsion delivers shorter, more powerful bursts. The discarded transfer module has no independent onboard computer or antenna and will remain in orbit around the Sun. Sources: [s1]() [s4]() The operation took place more than 200 million kilometres from Earth, without real-time human intervention. ESA reports that the remaining stack entered safe mode, adjusted its orientation and reconfigured before transmitting its status. A preliminary radio-frequency shift indicated separation before full confirmation arrived. For the operators, detecting that hardware had moved and confirming that the surviving system was powered and communicating were separate checks. Sources: [s1]() [s4]() ### The instruments still depend on the arrival sequence LIRA's new account makes the payload consequence concrete. Its visible-and-infrared imager channel on the European orbiter is intended to map surface minerals, while its high-frequency radio receiver aboard Mio will study Mercury's magnetic environment. The instruments need different orbital positions to perform those complementary jobs. Their presence aboard the spacecraft is not evidence that the planned orbital observing programme has begun. Sources: [s2]() The operator's next checkpoints are explicit: Mercury orbit insertion on November 21, separation of the science orbiters on December 9-10, then completion of the European orbiter's final science orbit in March 2027. Full science operations are planned for April. Universe Today's September 9 report also describes those remaining stages. For the instrument teams, the next test is getting each spacecraft into the position its measurements require. Sources: [s1]() [s2]() [s3]() [s4]() ## Conclusion Separates mechanical release, power and communications recovery, and orbital commissioning into distinct acceptance checkpoints. Connects the handover to the different observing positions needed by two named instrument functions, without equating separation with science readiness. ## Disclosures Sponsored: no Desk bylines, AI assistance and editorial policies: https://www.theroboteconomy.news/about/ ## Sources - s1: [BepiColombo begins Mercury arrival with MTM separation success]() — European Space Agency; official-record; 2026-09-07T00:00:00.000Z - s2: [Successful separation of the transfer module from the BepiColombo mission]() — LIRA, Observatoire de Paris; technical-document; 2026-09-08T00:00:00.000Z - s3: [BepiColombo Successfully Begins Its Final Descent To Mercury]() — Universe Today; independent-reporting; 2026-09-09T12:13:00.000Z - s4: [Latest updates: BepiColombo's arrival at Mercury]() — European Space Agency; official-record; 2026-09-03T13:52:00.000Z