The European-Japanese BepiColombo spacecraft has begun the most demanding stretch of its journey, according to reports from Bild der Wissenschaft and other outlets. After roughly eight years of flight, the probe has detached its propulsion module and is now coasting without power toward the planet Mercury.
The separation marks the start of what Bild der Wissenschaft describes as the "hot phase" of the mission. With its main engine no longer attached, BepiColombo is effectively in free fall, relying on gravity to carry it the rest of the way. The Frankfurter Rundschau reports that the spacecraft has now committed itself to this final, unpowered trajectory.
BepiColombo launched in 2018 and has traveled approximately nine billion kilometers to reach this point, according to focusplus.de. The mission is a joint effort between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA), though the source material does not specify JAXA's role in this final phase.
Mercury presents unique challenges for spacecraft. It is the closest planet to the Sun, meaning extreme heat and strong gravitational pull from our star make orbital insertion difficult. Der Standard calls it the most difficult planet in the solar system to reach, a reputation built on these harsh conditions.
The probe is expected to enter Mercury's orbit in the coming days, according to science.ORF.at. Once there, its two science orbiters will begin studying the planet's composition, magnetic field, and surface geology.
What to watch next: confirmation of a successful orbital insertion and the first science data from Mercury's harsh environment.
