During the navigational move, called Trajectory Correction Maneuver A, or TCM-A, in NASA jargon, the spacecraft fired its rockets for about five minutes, changing its velocity by 36 feet (11 meters) per second as it speeds along a path toward Comet Wild-2.
The maneuver took place nearly a year after Stardusts Feb. 7 launch aboard a Delta 2 rocket from Florida's Cape Canaveral Air Station.
"We had such an accurate injection from the Delta we didnt have to perform the correction most people have to do in the first week or two after launch," said Tom Duxbury, Stardusts deputy project manager and flight director at NASAs Jet Propulsion Laboratory.
The $165-million missions spacecraft should fly by Wild-2 on Jan. 2, 2004, collecting in the process the first cometary material to be returned robotically to Earth. Beginning on Feb. 22, 2000, and again in July 2002, the spacecraft will also collect samples of interstellar dust using the flip side of the collector plate.
The spacecraft then is designed to jettison a capsule containing all the samples in 2006, allowing it to parachute safely to a landing in Utah in January of that year.
Scientists are anxious to study comets firsthand because they are thought to preserve pristine examples of the building blocks of our solar system.
For most of their lives, comets lurk in the dark reaches of space, literally locked in a deep freeze beyond the warming rays of the sun.
Scientists think Wild-2 is an ideal candidate for study because until recently it spent most of its time far from the sun. A chance encounter with Jupiter in 1974, however, altered its orbit, sending it on a course that brings its within reach on a more regular basis.
It is only on approach to the sun that the increased warmth boils off material from the dirty snowballs, producing a distinctive tail and dust cloud, or coma.
Stardust will pick its way through that cloud during the 10-hour, 13,600 mph (22,000 kph) flyby, coming within 100 miles (160 kilometers) of the comets nucleus. The spacecraft will collect the particles in a glass foam called aerogel, nestled inside the clam-shaped return capsule. It will also image Wild-2s nucleus.
The spacecraft is also on track to fly by the asteroid Annefrank in November 2002, which would give mission members an opportunity to practice taking pictures of a small body similar to a comet.
During its 2.3-billion mile (3.7-billion kilometer) voyage to Wild-2, Stardust will make three loops of the sun and one swoop by the Earth on Jan. 15, 2001 to gain momentum.
Tuesdays move was in some ways a practice run of a much large action the spacecraft must carry out in three parts between Jan. 18 and 22. Called a Deep Space Maneuver, the spacecraft will change its velocity by 561 feet (170 meters) per second to modify the shape of its orbit. The smaller TCMs of which there will be 15 during the seven-year mission simply alter the spacecrafts course.
The maneuver also ended a quiet period for the Lockheed Martin-built spacecraft. To economize, the spacecraft shared the same flight team at Lockheed in Denver with the ill-fated Mars Climate Orbiter and Polar Lander. During most of the year, Stardust had taken a back seat to Mars missions, Duxbury said.
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