There are few places as immersive as planetariums. A simple star projection alone can make the construction of the theatre, with its walls and devices, seem to disappear. It replaces the space in which the guests are seated with another, a cosmic space. In this setting, the planetarium audience is in two spaces at the same time—a physical one and an imaginary one. Planetariums are exemplary places for a reality substitution—the physical world slides almost imperceptibly into a virtual one, which feels entirely “natural” in the case of projections of constellations although it goes far beyond a typical cinematic experience in terms of how we perceive visual stimuli and spatial sound because we are sitting in the centre of the image, inside the same space that is generating the images. Since the Sixties, generations of artists have been interested in the planetarium as a site of aesthetic experience. For them, the excellent infrastructure for projection and sound that the fulldome offers has turned the planetarium into a prime venue for artistic experimentation. At a time when we need to develop a new relationship with our planet based on connection and holistic thinking, their planetary perspective as well as their potential...