theres actually four of them or more maybe....the other one trying an ION ENGINE is called NEW DAWN....its way way out there in a short time frame and after inspecting the 2 bodies it will zoom off towards the 3rd mission that was postponed is my guess and then a speed run to see what it can do...PS...a XENON ION THRUSTER...you have 2 of those right now...they are called......HEADLIGHTS here on earth....LMAO
Propulsion system[edit]
The Dawn spacecraft is propelled by three xenon ion thrusters based on an evolution of the NSTAR technology used by the Deep Space 1 spacecraft,[38] and uses only one at a time. They have a specific impulse of 3,100 s and produce a thrust of 90 mN.[39] The whole spacecraft, including the ion propulsion thrusters, is powered by a 10 kW (at 1 AU) triple-junction gallium arsenide photovoltaic solar array manufactured by Dutch Space.[40][41] Dawn was allocated 275 kg (606 lb) of xenon for its Vesta approach, and carried another 110 kg (243 lb) to reach Ceres,[42] out of a total capacity of 425 kg (937 lb) of on-board propellant.[43] With the propellant it carries, Dawn can perform a velocity change of more than 10 km/s over the course of its mission, far more than any previous spacecraft achieved
https://en.wikipedia.org/wiki/Dawn_(spacecraft)