The satellite plataform was built of an aluminum alloy. It was a rectangular parallelepiped 62 cm by 62 cm wide by 80 cm high. Four deployable solar panels, covered by GaAs cells, generated 210 W to supply the electrical power to the various subsystems:

Attitude control  Thermal control Command and data handling RF communications as well as the instruments

The solar instruments (HXRS and GXRE solar detector) were mounted on the Sun-facing end of the spacecraft along with the Fine Sun Sensor, with fields of viewalways facing the Sun. The two GXRE gamma ray detectors were mounted on the solar platform, but their have fields of view were on opposite sides of the spacecraft,perpendicular to the sun. CUBIC and ISENA were mounted on the top, on the side of the spacecraft, facing the ground.The field of view of CUBIC was perpendicular to the un.