The X3 ion thruster is one of such developments. While it’s far from space-worthy, NASA is currently testing the 500-pound device at the Glenn Research Facility. The X3 proceeded to break records for operating current, power, and thrust generated by ion propulsion.

The first ion thrusters did not last very long, but the ion thruster on Deep Space 1 exceeded expectations and was used more than 16,000 hours during a period of over 2 years. On the road to getting humans to Mars, engineers from NASA and the University of Michigan have successfully tested the X3, a thruster designed to get us to Mars. The X3 thruster, which was designed by researchers at the University of Michigan in cooperation with NASA and the U.S. Air Force, is a Hall thruster … UM calls the X3 a prototype "Mars engine," … The ion thrusters being developed now are being designed to operate for 7 to 10 years. The ion thruster then processes the propellant and power to propel the spacecraft.

X3 is a Hall-effect thruster—a type of ion thruster in which the propellant (most commonly xenon) is accelerated by electric and magnetic fields. It already set three records in 2018, including highest power level for a Hall thruster, the highest level of thrust produced by any Hall thruster, and the highest amount of current passed through a Hall thruster.