On January 15, 2006, the sample return capsule from NASA's Stardust spacecraft parachuted onto the Utah desert. In addition to the particles collected during Stardust's encounter with comet Wild 2 in January of 2004 the spacecraft delivered tiny particles of interstellar dust that originated in distant stars, light-years away. Scientists estimate that Stardust collected 45 of these micron-sized interstellar dust particles using an aerogel collector 1,000 square centimeters in size.

Finding the individual dust particles, however, has been a challenge—made worse by the condition of the collector plates, which are interspersed with flaws, cracks and an uneven surface.

Through its Stardust@home citizen science project, University of California, Berkeley, researchers have invited Internet users to help them search for these few dozen submicroscopic grains of interstellar dust captured by NASA's Stardust spacecraft. The researchers took scans of the plates from a cleanroom at Houston's Johnson Space Center and made images of these scans available for public viewing via the Web. The dust grains will have made carrot-shaped trails in the aerogel, which is a silicon-based sponge 100 times lighter than water.