Fig. 6From: MMX geodesy investigations: science requirements and observation strategyExample of a 3D-QSO in Phobos-fixed rotating frame. A case with the in-plane size of 50 × 100 km and out-of-plane component up to Z = \(\pm\)50 km is depicted. The spacecraft position is shown in blue and Phobos’ shape is shown in redBack to article page