BepiColombo Begins Final Approach to Mercury — After nearly eight years and billions of kilometers of travel, BepiColombo — a science mission led by ESA in close collaboration with JAXA — has begun its long-awaited arrival at the smallest and innermost planet in our Solar System.
An artist’s impression of the ESA/JAXA BepiColombo spacecraft in cruise configuration, with Mercury in the background. On its 7.2 year journey to the innermost planet, BepiColombo will fly by Earth once, Venus twice and Mercury six times before entering into orbit. The MTM module is shown with ion thrusters firing, and with its solar wings extended, spanning about 100 feet (30 m) from tip-to-tip. The 24.6-foot (7.5 m) long solar array of the MPO orbiter in the middle is seen extending to the top. The Mio orbiter is hidden inside the sunshield in this orientation. Image credit: ESA / ATG Medialab / NASA / JPL.
BepiColombo blasted off from Europe’s Spaceport in Kourou, French Guiana, on October 20, 2018.
It is the first European mission to Mercury and is the first to send two spacecraft to make complementary measurements of the planet and its dynamic environment at the same time.
It consists of two individual orbiters: ESA’s Mercury Planetary Orbiter (MPO) and JAXA’s Mercury Magnetospheric Orbiter (MMO, or ‘Mio’).
BepiColombo is named after the Italian mathematician and engineer Giuseppe (Bepi) Colombo.
Professor Colombo was the first to see that an unsuspected resonance is responsible for Mercury’s habit of rotating on its axis three times for every two revolutions it makes around the Sun.
He also suggested to NASA how to use a gravity-assist swing-by of Venus to place the Mariner 10 spacecraft in a solar orbit that would allow it to fly by Mercury three times in 1974-5.
On September 3, 2026, mission controllers confirmed that the spacecraft’s Mercury Transfer Module (MTM) successfully separated from the rest of the stack, kicking off the mission’s ‘arrival phase.’
Confirmation came via two of ESA’s deep-space tracking antennas in Spain and Argentina, which picked up signals validating the separation.
Telemetry showed all systems functioning normally, with MPO’s solar panels already charging the spacecraft’s batteries.
The maneuver was a high-stakes one: it took place more than 200 million kilometers from Earth, a distance that ruled out any real-time troubleshooting and demanded exhaustive advance planning from mission teams.
With the transfer module gone, MPO and Mio orbiters are now headed toward orbit insertion at Mercury, with MPO powering the joined spacecraft until the two orbiters separate from each other.
“The arrival phase begins with the separation of MTM from the spacecraft stack on September 3, 2026,” members of the BepiColombo team said in a statement.
“The composite spacecraft will enter orbit around Mercury on November 21, 2026, and MPO and Mio will separate from each other on December 9-10, 2026.”