Upon arrival at Mercury in 2019, the components of the BepiColombo cruise-configuration spacecraft will separate. The transfer module will be ejected into space and the composite spacecraft, consisting of the Mercury Planetary Orbiter (MPO) and the Mercury Magnetospheric Orbiter (MMO), will use conventional rocket engines and the so-called 'weak stability boundary capture technique' to enter into polar orbit around the planet. When the MMO orbit is reached, the MPO will separate and lower its altitude to its operational orbit by chemical propulsion. Scientific investigations will go on for at least one Earth year (that is four Mercury orbits around the Sun).