The operation was the last of a three-part move called a Deep Space Maneuver designed to change the spacecrafts velocity by 561 feet (170 meters) per second. The change was so large, engineers chose to break it up into three parts -- performed on January 18, 20 and 22.

"It went nearly perfectly," said Tom Duxbury, the Stardust deputy project manager and flight director at JPL, of the final maneuver. "It was a nice conclusion to the three burns, so we are quite happy."

Engineers still need to perform a cleanup maneuver to compensate for extremely small errors resulting from the Deep Space Maneuver. Any cleanup burn would involve changing Stardusts velocity by less than 3 feet (1 meter) per second, engineers said.

Stardust will also have to perform two more Deep Space Maneuvers during its mission, although both will be much smaller. One will put it on target to the comet Wild 2; the second, to Earth to return samples of the dirty snowball.

"This was by far, by orders of magnitude, more difficult," Duxbury said.

Stardust will fly by Wild 2 on January 2, 2004, collecting the first-ever samples of cometary material to be returned robotically to Earth.

Before that, beginning on February 22, 2000, and again in July 2002, the spacecraft will also collect samples of interstellar dust streaming through space. During each collection period lasting a few months, the spacecraft will trap the minuscule particles in a collector plate packed with lightweight aerogel -- a glass foam.

Saturdays move put Stardust right on track to start collecting.

"The idea is to get maximum exposure of the collector to the stream," said Ken Atkins, the Stardust project manager.

The spacecraft will then jettison a capsule containing the samples in 2006, allowing it to parachute to a soft landing in Utah.