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APOD: An Ion Drive for Deep Space 1 Feature Summary
- From Physics Research
Astronomy Picture of the Day: Ion Drive for Deep Space 1
- This Astronomy Picture of the Day shows a laboratory test of the ion drive engine that propelled the probe Deep Space 1 to the outer reaches of the solar system.
-- The little solar-powered engine, only about 40 cm on a side, ionized xenon atoms and expelled them at about 100,000 km/s, exerting a small reaction force on the spacecraft over a long period of time.
-- The engine's thrust was small, as was the corresponding acceleration, but since the engine ran for weeks at a time, the final speed was substantial. To find out more about this probe and its unusual engine, visit Astronomy Picture of the Day: Ion Drive for Deep Space 1 and Deep Space 1.
- image credit: New Millennium Program, JPL, NASA; image source; larger image
- Image URL:
- May 1, 2009 - May 16, 2009