The BepiColombo ‘ministack’, comprising JAXA’s Mercury Magnetospheric Orbiter (top) and ESA’s Mercury Planetary Orbiter (bottom), transferring between facilities at Europe’s Spaceport in Kourou. The modules spent the first part of the launch campaign in the ‘processing area’ before moving to the ‘fueling integration area’ where the chemical propulsion fueling activities will take place.
In this view the MPO’s radiator side is visible – the radiator ‘fins’ have now been installed. The radiator is designed to reflect heat directionally, allowing the spacecraft to fly at low altitude over the hot surface of planet Mercury.