In-orbit collisions and decreasing satellite orbits have shown that orbital debris poses a threat to space or a threat to the ground. A very promising solution under study at CNES is to clean low-altitude orbits by injecting debris. The EntrySat mission aims to put into orbit a 3U nanosatellite. The payload of the nanosatellite will make it possible to study the environment around the satellite and its attitude until its destruction. Since this satellite will have no means of propulsion or means of protection, it will behave like an orbital debris. It will increase our knowledge of the behavior of orbital debris when they fall in the Earth’s atmosphere. EntrySat is a mission proposed by ISAE-SUPAERO and funded by CNES as part of the Janus program.