BepiColombo Reaches Final Approach to Mercury After 8 Years

BepiColombo Sheds Propulsion Module 39 Million Miles From the Sun

The separation of the Mercury Transfer Module occurred 39 million miles from the Sun, an extreme environment featuring intense solar radiation and temperatures less than half the distance of Earth. Ignacio Tanco, head of inner Solar System mission operations at ESA, told reporters that the complex maneuver carried considerable risk, comparing it to launching a new spacecraft.

Because BepiColombo was over 200 million kilometers from Earth during the maneuver, the one-way communication time lag was approximately 11 minutes, ruling out any real-time control by ground operators. Letting go of the transfer module required the remaining spacecraft to independently take over power generation, thermal control, propulsion, and attitude pointing. The propulsion module previously obscured several core science instruments, which Tanco noted will finally see first light following the release.

Orbital Insertion and Dual-Spacecraft Science Strategy

The mission’s full scientific operations are scheduled to begin in April 2027.

The two orbiters feature distinctly complementary designs tailored to survive Mercury’s brutal environment, where thermal extremes exceed 400°C alongside fierce solar radiation. The European Mercury Planetary Orbiter will descend into a low polar orbit to map surface topography, internal structure, and elemental composition using thermal blankets and a sun-tracking solar array. Simultaneously, JAXA’s Mio orbiter will enter an elongated orbit, utilizing a spin-stabilization mechanism that rotates 15 times per minute to distribute heat across its mirror-like exterior shades while analyzing the planet’s magnetic field and surrounding plasma environment.

Frequently Asked Questions

When will BepiColombo enter Mercury’s orbit?

According to mission schedules reported by aerospaceglobalnews.com, BepiColombo is set to enter orbit around Mercury on November 21, 2026.

When did the BepiColombo mission launch?

The joint European and Japanese mission launched from Earth on October 20, 2018, aboard an Ariane 5 rocket from Europe’s Spaceport, according to aerospaceglobalnews.com.

Why did the spacecraft separate from the Mercury Transfer Module?

The propulsion module was no longer required for propulsion once the spacecraft reached its arrival phase, and its removal uncovers the mission’s primary science cameras and instruments just ahead of orbital capture, according to ESA statements.

What are the primary goals of the two orbiters?

The European Mercury Planetary Orbiter will map the planet’s surface and interior structure, while JAXA’s Mio orbiter will analyze Mercury’s magnetic field, plasma, and solar wind interactions.