SAMPLE COLLECTION

In February, 2000, the Stardust spacecraft successfully deployed its aerogel collector and began capturing interstellar dust from a stream of particles from outside our solar system that was initially detected many years ago by Earth-orbiting spacecraft. This historic first collection period lasted through May 1. The collector was then returned to its stowed position until mid-2002, when the second interstellar dust collection took place from August through December.

Dust collector with aerogel (Click image for full size view)

Stardust passed a huge milestone on January 2, 2004, when it flew within 240 kilometers (149 miles) of the nucleus of Comet Wild 2, collecting samples of comet dust and snapping detailed pictures of the comet's surface. To collect the particles without damaging them, Stardust used a collector the size of a tennis racket and a substance called aerogel, a silica-based solid with a porous, sponge-like structure in which 99 percent of the volume is empty. The collector was then stowed in the sample return capsule for the two-year journey back home.

SAMPLE RETURN

The Stardust sample return capsule returned safely to Earth at 3:10 a.m. local time on January 15, 2006. Parachuting into the desert salt flats of the U.S. Air Force Utah Test and Training Range after a 288 billion mile journey through the Solar System, the SRC entered the Earth's atmosphere faster than any human-made object on record. It slowed from a speed of nearly 29,000 miles per hour to about 10 miles per hour in 13 minutes.

Stardust sample return capsule after landing in Utah.

Eager science team members transported the science canister to the curation facility at NASA's Johnson Space Center in Houston, TX, to begin the process of extracting the dust particles from the aerogel.

Early analyses of the comet dust particles surprised scientists. They found high-temperature minerals in materials from the coldest place in the Solar System, suggesting that materials from the center of the solar system could have traveled to the outer reaches where comets formed. This may alter the way scientists view the formation and composition of comets. They may prove to be more diverse and complex than previously thought.

One mineral found in the material brought back by Stardust is olivine, a primary component of the green sand found on some Hawaiian beaches. It is among the most common minerals in the universe, but scientists were surprised to find it in cometary dust.

Olivine found in comet dust returned by Stardust.

The collection of cometary particles is greater than expected, with about two dozen large tracks visible to the unaided eye. Thousands appear to be embedded in the aerogel, most smaller than a hair's width.

STARDUST@HOME

Before they can be studied, the miniscule interstellar grains have to be found, which is not easy. Unlike the thousand of particles of varying sizes collected from the comet, scientists estimate that Stardust collected only around 45 interstellar dust particles. And they are tiny - only about a micron (a millionth of a meter) in size, embedded in an aerogel collector about 155 square inches in size. The Stardust@Home project invites the public to join the search with the aid of a special Virtual Microscope (VM) that works in your web browser.

MISSION MANAGEMENT

The Stardust mission was managed by the Jet Propulsion Laboratory. The Principal Investigator was Dr. Donald Brownlee of the University of Washington. The Stardust spacecraft was designed and built by Lockheed Martin Astronautics of Denver, Colorado.
For more information, visit the Stardust homepage.