21. On 4 November 2009, the ion engine D automatically stopped working due to an anomaly from degradation. 22. Cautious ground controllers will wait a week or two before firing up Deep Space 1's ion engine . 23. Deep Space 1's ion engine will run on 180 pounds ( 82 kilograms ) of xenon gas. 24. :: The same might happen to ion engines and anything that follows ( for quite some time ). 25. In the much slower real world, solar-powered ion engines are 10 times more efficient than traditional chemical engines. 26. Or, this might be a good application for ion engines , which are more efficient, but have very low thrust. 27. One mission proposed using the electricity to power ion engines , calling this method radioisotope electric propulsion ( REP ). 28. On 28 August, " Hayabusa " was switched over from the ion engines to the bi-propellant thrusters for orbital maneuvering. 29. Rayman says that, over time, ion engines can deliver 10 times more thrust per pound of fuel than chemical rockets. 30. To avoid a lapse in propulsion, the mission team hastily exchanged the active ion engine and electrical controller with another.
