2 spacecraft headed to Mercury are about to begin their long-awaited arrival for Europe and Japan — watch it live on Sept. 3

The BepiColombo mission, a joint effort between Europe and Japan, is set to arrive at Mercury on September 3, 2025. After an extensive journey that began in October 2018, the mission's two science orbiters, one operated by the European Space Agency (ESA) and the other by the Japan Aerospace Exploration Agency (JAXA), are preparing for their rendezvous with our solar system's innermost planet.

The two orbiters will detach from their power and propulsion module on September 3 at approximately 8 a.m. EDT (1200 GMT). The live webcast of this event, organized by ESA, will begin at 7:45 a.m. EDT (1145 GMT) and will cover the momentous separation. Just one hour later, at 8:30 a.m. EDT (1230 GMT), the webcast will pause as the mission teams establish communication with the newly independent orbiters.

Signals are expected to be received by 9:53 a.m. EDT (1353 GMT), according to ESA officials. The webcast will continue with status checks and conclude between 10:15 and 10:45 a.m. EDT (1415 to 1445 GMT).

Once separated, the two science orbiters, the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO), will not be captured by Mercury's gravity until November 21, 2025. At that time, MPO will release Mio into its final orbit—a highly elliptical path ranging from 367 miles (590 kilometers) to 7,233 miles (11,640 kilometers) from Mercury—on December 9 or 10. Following this, MPO will embark on its own designated path a week later.

MPO is slated to reach its final orbit, characterized by altitude extremes of 298 miles and 932 miles (480 to 1,500 kilometers), on March 10, 2027. The mission's science phase commences on April 6, 2025, and is expected to provide fascinating insights into Mercury. MPO will create a comprehensive map of the planet at various wavelengths, while Mio will focus on studying Mercury's magnetosphere, aiming to unravel the mysteries surrounding the least explored body in the inner solar system.