The PROBA-3 mission is actually compound of 2 spacecraft: the “Coronagraph spacecraft” bearing the telescope instrument and the “Occulter spacecraft” bearing the external occulter, 144 m apart. The external occulter masks the direct light coming from the solar disc to the aperture of the telescope, thus producing an artificial eclipse.

The weight of the Coronagraph and Occulter spacecraft are about 340 kg and 200 kg, respectively.