Recent innovations to advance space electric propulsion technologies

While many types of mature space propulsion systems are in active use, significant progress is still required to meet the requirements of new missions. The emerging challenges include plans for Mars and Moon exploration, building huge satellite constellations like Starlink and OneWeb, advanced astrophysical studies including space-based gravitational wave detection systems, precise astrophysical and astronomical measurements in space, search for life on exoplanets, deep space missions, and others. In this light, this review outlines and briefly discusses the most recent, advanced and innovative approaches, technologies, concepts, and physical principles related to space propulsion. Furthermore, we present more ambitious ideas for the future that have been demonstrated in labs as prototype space systems to enhance the performance of mature space propulsion thrusters and concepts that are proposed for consideration in future space thruster systems. We discuss the recent advances in the application of advanced rotating magnetic field systems for space propulsion, condensable propellant thrusters, innovations in propellant supply systems, capillary and narrow channel thrusters, staged thrusters, application of segmented electrodes, and other techniques. The manuscript brings to light the most recent innovations for future consolidated research efforts worldwide, helps to define the key parameters of space propulsion systems for future ambitious missions, and ultimately contributes to the creation of substantially novel thrust platforms for future space exploration.