Sacramento, Calif.-based Aerojet said June 29 that a xenon ion engine developed in partnership with NASA’s Glenn Research Center has surpassed 30,000 hours of operation in ground tests at the Cleveland-based NASA field center.

Developed under NASA’s Evolutionary Xenon Thruster program, the ion engine is designed to provide a small, constant thrust over long periods of time in order to accelerate spacecraft to thousands of kilometers per hour while using less than a tenth of the propellant of conventional chemical rockets. A previous-generation ion engine is currently propelling NASA’s Dawn spacecraft toward its 2011 encounter with the asteroid Vesta.

NASA’s Glenn Research Center manufactured the test engine’s core ionization chamber. Aerojet designed and built the ion acceleration assembly, which the company says is key to the long life and high performance of the thruster.

The assembly has more than 25,000 holes precisely etched in a pair of thin plates 50 centimeters across.