PRISMA satellites

The PRISMA mission will consist of two satellites

The main satellite, MANGO, with a mass of 140 kg with full 3-axis reaction wheel based attitude control and 3-axis delta-V capability
The target satellite, TANGO, of 40 kg with coarse 3-axis attitude control based on magnetometers, sun sensors and magnetic torquers.

Their relative position is measured by different sensors depending upon the experiment and the satellite distance:

Differential GPS: The differential GPS system provided by DLR is the main relative positioning measurement system on PRISMA, and experiments will mainly be carried out for inter-satellite distances over 30 m. The system is based on fully redundant set of Phoenix receivers and antennas on each spacecraft.
Visual based sensor (VBS): Based on a star tracker used in many microsatellite missions, this sensor provided by DTU will be used in order to identify TANGO as a non-stellar object at distances up to 500 km, and to track TANGO down to very close range, typically 10 meters during a sequence of autonomously scheduled approach maneuvers.
The RF metrology subsystem (FFRF): Designed to handle first stage omnidirectional metrology, the FFRF provided by CNES will mainly function at inter-satellite distances from 3 m to 30 km.

The MAIN spacecraft is equipped with the following sensors: magnetometers, sun sensors, angular rate sensors, accelerometers, star trackers/VBS, GPS receivers as well as a FFRF Terminal and three antennas. These last equipments are part of the FFIORD experiment.

The TARGET satellite is equipped with the following sensors: magnetometers, sun sensors, GPS receivers as well as a FFRF Terminal and three antennas. These last equipments are also part of the FFIORD experiment.

The two satellites will be clamped during the launch.
They will be sent in Orbit by a DNEPR launcher as a companion of CNES PICARD satellite.
They will be put on a sun-synchronous LEO (Low Earth Orbit) at 710 km altitude.
The mission will last 10 months and will be controlled from Solna, Sweden.