Researchers hope the preserved material will reveal new details about the origins of the planets and the sun.
The 3 a.m. Sunday landing at the U.S. Air Force Utah Test and Training Range marks the end of a seven-year journey during which the Stardust spacecraft buzzed a comet in 2004 to collect debris.
''The Stardust capsule is back on Earth, back home and it's in our hands,'' said Andy Dantzler, director of NASA's solar system exploration division.
There were moments of tension as scientists and engineers followed the capsule's progress. Mission controllers on NASA TV reported that the drogue parachute, the first of two to deploy, did not appear to have opened.
''Come on, pop the chute,'' whispered Carlton Allen, of NASA's Johnson Space Center, who watched the return on TV with reporters. ''Pop the chute, pop the chute.''
Later, researchers said they knew that the drogue chute had indeed opened.
''When we saw that drogue parachute open,'' said Thomas Duxbury, project manager at NASA Jet Propulsion Laboratory, in Pasadena, Calif, ''we knew we were home safe.''
Many involved may have briefly feared a repeat of the ill-fated Genesis mission. That NASA probe slammed into the desert in Sept. 2004 after both parachutes failed to deploy. Sensors were installed backwards to cause the chute failure.
''No matter what people say about Genesis, it's a huge deal when you have a situation like that and you're following it,'' said Don Brownlee, principal investigator at the University of Washington, Seattle
This time around, the main chute calmed most of those watching on TV.
''Yes, yes, yes,'' chanted Allen as he pumped his fists upon learning about the main chute. Allen, who is the astromaterials curator at Johnson Space Center in Houston, will soon get his hands on the samples that will be distributed to dozens of scientists.
''Now, the science mission is going to begin,'' he said.
The collected samples wouldn't cover the bottom of a salt shaker, but scientists consider this a massive haul. The largest pieces still measure less than the width of a human hair.
Researchers will need to slice up the each piece of the sample return. On Tuesday, crews are scheduled to drive the samples to Johnson Space Center.
Scientists anticipate years of study from the debris.
''It's the gift that keeps on giving,'' said Tom Duxbury, project manager at NASA's Jet Propulsion Laboratory, in Pasadena, Calif.
It took several years to line up with Wild 2 comet, which formed at the edge of the solar system. It remained in deep space until a close encounter with Jupiter in 1974 sent the icy comet into a new orbit that now passes through the inner solar system.
Because it has only come close to the sun a few times, researchers hope that the material is mostly pristine still. The debris is believed to be the original building blocks of the solar system.
While meteorologists predicted cloudy conditions, the skies opened shortly before the probe re-entered the atmosphere. Viewers at Dugway Proving Ground could see the probe, which resembled a shooting star, as it hurtled toward Utah.
The capsule sliced through the atmosphere over the Pacific Ocean, hitting a top speed of more than 28,000 mph. The heat shield reached 4,900 degrees during the re-entry.
About 6,000 above the west desert, the main parachute deployed easing the craft to a landing on the moist salt flats.
''This thing went like clockwork,'' said Tom Duxbury. The capsule bounced several times before coming to a stop.
Helicopter crews finally spotted the mud-encrusted probe around 4 a.m. using infrared cameras and following the probe's radio beacon, said Joe Vellinga, part of the recovery team from Lockheed Martin Space Systems.
A trio of helicopters teamed to check the landing site and load the capsule for the short flight to a clean room near Michael Army Air Field.
A team spent the morning working in the clean room to remove the sample return cannister -- which houses the comet debris. NASA will fly the samples to Johnson Space Center on Tuesday, where scientists will begin unloading the cometary cargo.
''We're on the one yard line,'' said Vellinga. ''The real touch down is when we open (the cannister) up Tuesday.