Miniature Water Ion Thruster; 1 km/s-class Delta-V for a 6U CubeSat

A propulsion system gives CubeSats the capacity to change their orbit on their own, and in terms of achieving a large delta-V, electric propulsion has an advantage. Installing the electric propulsion on CubeSats has difficulties such as a high-pressure gas system, electrical components, and the drop of the efficiency because of the miniaturization. To clear these problems, the water ion thruster is proposed as a candidate for the CubeSats’ electric propulsion. Water has an absolute advantage of applying for CubeSats’ propulsion system in the point of safety. In addition, water is a liquid phase at room temperature and atmospheric pressure, and it makes easy to store and handle it. The thrust measurement and the improvement of the thruster based on experiments were conducted. The thrust and the specific impulse were estimated as 226 ± 19 μN and 384 ± 33 s at the highest performance point with 36.5 W power consumption of all system. It achieved a delta-V of 504 ± 43 m/s with the 1 kg of propellant for an 8 kg and 6U CubeSat

AQUARIUS: The World\u27s First Water-Based Thruster Enabled 6U CubeSat to Complete Lunar Flyby

This paper presents the outcomes of the initial operations and on-orbit performance of AQUARIUS (AQUA ResIstojet propulsion System), a micro-propulsion system. AQUARIUS utilizes water as a propellant and is designed for trajectory control and reaction wheel desaturation of a 6U CubeSat, EQUULEUS (EQUilibriUm Lunar-Earth point 6U Spacecraft). The spacecraft was launched in November 2022 by SLS, following which the initial operations commenced. Both the spacecraft and the propulsion system were confirmed to be in good health during the checkout process. Performance evaluation of the propulsion system confirmed that it met the requirement to execute the first delta-V maneuver scheduled 38 hours after separation from the launch vehicle. The delta-V maneuver was successfully completed, achieving a total delta-V of 6.48 m/s. The propulsion system demonstrated an average thrust of 5.94 ± 0.21 mN. Subsequently, precise trajectory control maneuvers were carried out, resulting in a successful lunar flyby. As a result of these initial operations, AQUARIUS became the world\u27s first water propulsion system to successfully control its orbit in deep space