BepiColombo Begins Its Arrival at Mercury Ahead of Orbit Insertion
The ESA-JAXA mission shed its transfer module on September 3, 2026, starting the final approach to Mercury orbit insertion on November 21.
BepiColombo, the joint ESA and JAXA mission to Mercury, has begun its arrival phase after eight years crossing the inner Solar System. The phase started on September 3, 2026, when the Mercury Transfer Module, the propulsion stage that carried the spacecraft stack, separated. ESA is tracking each step on its mission updates page.
The mission will be the first to orbit Mercury with two spacecraft: ESA’s Mercury Planetary Orbiter (MPO) and JAXA’s Mio. Orbit insertion is scheduled for November 21, 2026. MPO and Mio are due to separate on December 9 and 10, and science operations should start in April 2027.
The spacecraft is already busy. On September 15 all MPO instruments were switched on together for the first time, and the BELA laser altimeter, which will measure the height of Mercury’s surface, fired more than 700,000 pulses in 21.5 hours. On September 24, MPO fired its thrusters for 8 minutes 42 seconds, a course correction of 11.4 m/s.
Mercury is hard to reach because a spacecraft falling toward the Sun picks up speed and must shed it to be captured into orbit, which is why the trip took so long (our video library includes a good explainer on the orbital mechanics). Once in place, two orbiters working together will map Mercury’s surface, interior and magnetic environment in more detail than any mission before. Orbit insertion is the critical step still ahead. More on the innermost planet in our Solar System guide and our telescopes and missions guide.
What to watch next: orbit insertion on November 21, 2026, then the separation of MPO and Mio in December.
Primary source
This summary is based on ESA. Read the original for full details, data and caveats.
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