Two orbiters bound for Mercury
BepiColombo
BepiColombo is a joint mission of the European Space Agency and the Japan Aerospace Exploration Agency. Launched in October 2018, it carries two orbiters that will study Mercury from different orbits.
Reaching Mercury is surprisingly hard: a spacecraft falling towards the Sun speeds up, so BepiColombo used nine planetary flybys and electric propulsion to brake enough to be captured.
Key facts
- Agency
- ESA / JAXA
- Launched
- 2018-10-20
- Launch vehicle
- Ariane 5
- Power
- Solar arrays; solar-electric propulsion during cruise
- Mission type
- Two Mercury orbiters
- Named after
- Italian mathematician Giuseppe 'Bepi' Colombo
- Status
- Arriving at Mercury
Where it is now
Loading live position from NASA/JPL Horizons…
Mercury orbit, scheduled from late 2026.
Mission objectives
The mission will map Mercury's surface and composition, study its interior and unusually large iron core, investigate its magnetic field and magnetosphere, and examine its thin exosphere.
The spacecraft
BepiColombo travels as a stack of three modules: ESA's Mercury Planetary Orbiter, JAXA's Mercury Magnetospheric Orbiter Mio, and a transfer module whose ion engines provided thrust during the cruise. The stack separates on arrival.
Journey so far
After one Earth flyby and two Venus flybys, BepiColombo flew past Mercury six times between October 2021 and January 2025, returning close-up images and measurements along the way. Arrival in orbit around Mercury is scheduled for late 2026.
Route and timeline
- 2018-10-20Launch on Ariane 5, Kourou
- 2020-04-10Earth gravity assist
- 2020-10-15First Venus gravity assist
- 2021-10-01First of six Mercury flybys
- 2025-01-08Sixth and final Mercury flyby
- 2026-11Mercury orbit insertionplanned
Surprising facts about BepiColombo
- It needed more flybys to reach Mercury than Voyager 2 used to visit four planets.
- Its two orbiters will study Mercury from different altitudes at the same time.
- Giuseppe Colombo first explained Mercury's 3:2 spin–orbit resonance.
Keep exploring
- Parker Solar Probe: the spacecraft that touched the sun
- Solar Orbiter: the first views of the sun's poles
- JUICE: europe's explorer of jupiter's icy moons
- Explore Mercury in interactive 3D
- Explore Venus in interactive 3D
- Explore Earth in interactive 3D
- Follow every mission live in the 3D tracker
- All spacecraft guides