To study Mercury's surface, inside, exosphere, and magnetosphere, the MPO orbiter payload is constituted of:
- a set of imagers (SIMBIO-SYS) comprising a high resolution camera, a stereoscopic camera and a visible, and near infrared spectrometer (VIHI);
- a thermal infrared spectrometer and a radiometer (MERTIS);
- a laser altimeter (BELA);
- a UV spectrometer (PHEBUS);
- two X-ray spectrometers and a solar particle detector (MIXS et SIXS);
- a neutron and gamma ray spectrometer (MGNS);
- a magnetometer (MERMAG);
- a neutral and ionized particle analyzer (SERENA);
- a radio science experiment and an accelerometer (MORE and ISA).
The allocations of this payload are a mass limited to 60 Kg and a power of 100W.