This animation shows the Mercury Approach Phase (MAP) of the BepiColombo mission.
Still attached, the two orbiters are caught by Mercury as they enter the planet's gravitational sphere of influence. Next, using both the planet's gravity and the chemical propulsion system of the Mercury Planetary Orbiter (MPO) the two attached orbiters will enter orbit around Mercury.
The MPO's chemical propulsion system is used to lower the periherm and apoherm altitude until the size of the operational orbit is reached for the Mercury Magnetospheric Orbiter (MMO), some two weeks after capture by the planet. Here the MMO will separate from the MPO, after which the protective Sunshield and MMO interface structure are also jettisoned. The MMO will operate in a polar orbit with a periherm altitude of 400 km, an apoherm altitude of 12 000 km, and a 9.2 hour period.
After separation, the MPO's chemical propulsion system is used to further lower the orbit of the MPO alone. A series of braking burns lower the apoherm altitude until the MPO reaches its operational orbit: 400 × 1500 km polar orbit with a period of 2.3 hours.