To prepare for Tuesday's planned activities, the spacecraft successfully executed a large turn Friday, October 30, to point the ion engine toward the Sun. While the spacecraft remained in that orientation, a small amount of xenon from the ion propulsion system was allowed to flow through the system to assure there were no blockages. The spacecraft returned to its previous orientation the next day. On Thursday, November 5, a heater inside the thruster's cathode was turned on and the xenon system was pressurized. As a final test before thrusting, xenon was ionized inside the thruster on Monday, November 9, but was not accelerated.
Engineering data show that the test went as planned.
The suite of diagnostic sensors onboard to measure the effects of the ion propulsion system on the local space environment worked as planned. Once Tuesday's behavior is diagnosed and resolved, the engine is scheduled to be turned on intermittently for the remainder of the mission, which ends in late September 1999. The ion engine is among 12 technologies being tested on Deep Space 1, the first mission of the New Millennium Program, designed to validate new technologies so that they may be used on space missions of the 21st century.