BepiColombo Enters Mercury Arrival Phase, Separation Set for December 2026

BepiColombo has entered the final phase of its journey to Mercury, triggering the sequence of events that will place two spacecraft around the planet. The mission, a collaboration between the European Space Agency and the Japanese Aerospace Exploration Agency, will culminate with the separation of its science orbiters on 9th or 10th December 2026 – the moment that officially marks arrival at the innermost world.

BepiColombo is a joint ESA/JAXA mission that carries three elements: the Mercury Planetary Orbiter (MPO) from ESA, the Mercury Magnetospheric Orbiter (Mio) from JAXA, and the Mercury Transfer Module (MTM) that has provided propulsion and steering during the cruise.

After completing nine planetary flybys, the stack has now started the critical steps needed for arrival at Mercury.

On 2026-09-03 the MTM will release MPO and Mio. The two orbiters will then coast and be captured by Mercury’s gravity on 2026-11-21. Finally, on 2026-12-09 or 2026-12-10 they will part ways; that separation is defined as the official arrival at Mercury.

After arrival, Mio will enter its science operation orbit, while MPO is scheduled to reach its final science orbit on 2027-03-19.

ESA is running a public competition tied to the arrival, accepting a photo or video with a brief description posted as a public social media post with a link. Entries are open from 2026-09-15 to 2026-10-25 only to residents of ESA Member, Cooperating and Associate States who are over 18, and any adults appearing in the imagery must have given consent.

The agency will accompany the arrival with a live transmission from ESA’s Space Operations Centre in Darmstadt, Germany, on 2026-12-09 beginning at 22:00 CET.

Although BepiColombo is a Mercury mission, the multi‑module separation, precise interplanetary navigation, and autonomous orbit‑insertion techniques it demonstrates are directly relevant to the design of future lunar transfer stages and cislunar logistics. The event provides a rare public view of deep‑space arrival operations conducted jointly by two major space agencies, ESA and JAXA, both of which are also active in lunar exploration.

The MTM will release MPO and Mio on 2026-09-03, leading to a gravity capture on 2026-11-21. The definitive arrival occurs on 2026-12-09/2026-12-10 when the two orbiters separate. MPO will then descend to its final science orbit by 2027-03-19.

A public arrival competition is accepting entries until 2026-10-25, and a live event from ESA’s Space Operations Centre in Darmstadt is planned for 2026-12-09 at 22:00 CET.