# Europe's $2 Billion BepiColombo Probe Prepares to Orbit Mercury

> After eight years and nine planetary flybys, BepiColombo is shedding its cruise module for a risky insertion into Mercury's orbit.
- Title: Europe's $2 Billion BepiColombo Probe Prepares to Orbit…
- Summary: After eight years and nine planetary flybys, BepiColombo is shedding its cruise module for a risky insertion into Mercury's orbit. Reaching Mercury's orbit…
- Keywords: space, astronomy, mercury, bepicolombo, esa, technology, science, Europe's, Billion, Probe, Prepares, Orbit
- Source: Ars Technica — https://arstechnica.com/space/2026/09/after-8-years-europes-bepicolombo-mission-is-on-final-approach-to-mercury
- Published: 2026-09-04T22:49:17+00:00
- Read time: 2 min
- Topics: space, astronomy, mercury, bepicolombo, esa, technology, science
## Final approach to Mercury
Europe and Japan's nearly $2 billion BepiColombo mission has reached a critical milestone after an eight-year interplanetary voyage.
## Harder to reach than Pluto
Entering orbit around Mercury requires more orbital energy, or delta-v, than sending a spacecraft flying past distant Pluto.
## An unprecedented trajectory
To slow down enough for Mercury's gravity to capture it, BepiColombo required nine planetary flybys and powerful electric ion propulsion.
## Jettisoning the cruise module
With the long cruise complete, the spacecraft successfully detached its Mercury Transfer Module, which provided power and propulsion during transit.
## Three spacecraft in one stack
BepiColombo traveled as a three-part stack comprising the discarded transfer module, Europe's planetary orbiter, and Japan's magnetospheric orbiter, Mio.
## High risk near the Sun
Separating the module just 39 million miles from the Sun posed significant risks, forcing the remaining orbiters to immediately take over power and thermal control.

> This is something that we will only see after separation if it has worked
## First light for main cameras
Separation unblocked BepiColombo's primary scientific cameras. Telemetry confirms the remaining orbiters are generating power and recharging batteries.

> We have confirmation that the power margins on the spacecraft are positive
## Overcoming propulsion setbacks
Despite losing partial thruster power in 2024 and extending cruise time by a year, the probe has logged 6 billion miles and will orbit on November 21.
## Honoring an orbital pioneer
The mission honors Giuseppe 'Bepi' Colombo, the mathematician who devised planetary flyby trajectories for NASA's Mariner 10 mission in the 1970s.
## Unlocking polar ice and composition
Scientists aim to analyze Mercury's composition in new wavelengths and inspect dark polar crater floors that may harbor water ice.

> We want to look at it in new colors beyond what we can see with our own eyes
## Dual orbiters, unprecedented views
Releasing two orbiters into distinct altitudes will let Europe and Japan simultaneously measure Mercury's surface features and its interaction with solar winds.

> Having two spacecraft there is groundbreaking
## Key takeaway

Reaching Mercury's orbit takes more energy than flying past Pluto, requiring complex flybys, electric propulsion, and joint orbiter technology.