'A new mission starting today': 8 years after launch, BepiColombo begins Mercury arrival

After nearly eight years traveling through the inner solar system, the trailblazing BepiColombo spacecraft has finally begun its arrival at Mercury.

The joint European Space Agency (ESA)-Japanese Aerospace Exploration Agency ( JAXA ) mission reached a major milestone today (Sep.

3), entering its arrival phase at one of our sun's least-studied planets.

BepiColombo's Mercury Transfer Module (MTM), the main power and propulsion system that has ferried a dual stack of planetary probes through space for nearly eight years, released its payload to kick off a sequence of operations that will ultimately place the two spacecraft in Mercury's orbit.

The separation left ESA's Mercury Planetary Orbiter (MPO) and JAXA's Mercury Magnetospheric Orbiter, known as Mio, together for their final approach, which will take about six more months.

"It will basically be a new mission starting today," said Bruno Sousa, ESA's head of operations definition and engineering, during today's mission livestream.

BepiColombo launched aboard an Ariane 5 rocket from Europe's Spaceport at the Guiana Space Center in Kourou, French Guiana, on Oct.

19, 2018, beginning a journey that was expected to take about seven years.

To assist its plunge sunward, the spacecraft's trajectory has included one flyby of Earth , two of Venus and six of Mercury , as it has shed more and more gravitational energy during to slow its approach to the system's innermost planet.

"It's one of the most complicated missions we have ever flown," Sousa said.

The mission was made even more complicated in April 2024, when a solar panel issue reduced the available power for MTM's electric thrusters.

Engineers devised a lower-thrust trajectory that saved BepiColombo's mission but delayed its Mercury arrival from December 2025 to November 2026.

Today's maneuver doesn't place BepiColombo in orbit around Mercury quite yet.

MPO and Mio will spend the next several weeks navigating toward the planet ahead of orbital insertion on Nov.