In order to maintain the City of Space at an international level of performance and to meet the expectations of visitors, the renewal of the planetarium equipment that has become obsolete is necessary. The renovation project consists of the technological adaptation of the various rooms of the Cité de l’Espace (Planétarium and Stellarium). In the end, the latter will be able to offer its visitors three complementary immersive rooms, allowing for very attractive differentiated experiences: in addition to the frontal 3D relief on a giant flat screen already existing in the IMAX room, the 360° 2D hemispheric immersion in the Planetarium and the 3D immersion astronomical relief in the Stellarium.