Actuating device of a spacecraft by reflection of light on an astral auxiliary mirrors oriented differently

A device (D) is dedicated to actuating a spacecraft (S) and includes i) a fixed primary mirror (M1) for reflecting light from a celestial body in the form of a primary light beam, ii ) a secondary mirror (M2) reflecting in a selected direction at least part of the primary light beam as a secondary beam, iii) at least two auxiliary mirrors (MA1-MA8) placed at selected locations and loaded with reflecting at least a portion of the secondary light beam from the secondary mirror (M2) in different directions chosen in order to induce different displacements of said spacecraft (S), and iv) selective positioning means (MP) responsible for cause selective reflection of the secondary light beam towards at least one auxiliary mirrors (MA1-MA8), so that its reflection on the (s) mirror (s) auxiliary (s) induces a selected displacement of the spacecraft (S).