Stardust was a NASA Discovery Mission launched in 1999. Its main objective was to visit a comet and collect and return dust from it for study on Earth. In January 2004, the Stardust spacecraft flew through the coma of comet Wild 2 (pronounced “Vilt” 2). It carried a two-sided hypervelocity particle collector consisting of an array of tiles made of a strange material called aerogel. The array is about 40 cm (16 inches) in diameter. Stardust captured thousands of cometary dust grains in the collector. Two years later, in January 2006, Stardust returned these dust grains to Earth. It was the first mission to return solid extraterrestrial material to Earth from beyond the Moon.
In addition, Stardust carried an equally important payload on the opposite side of the cometary collector: the first samples of contemporary interstellar dust ever collected. Certain types of ancient interstellar dust-older than the Solar System (about 4.6 billion years)-have been isolated from meteorites and analyzed. In contrast, the interstellar dust collected by Stardust comes directly from local interstellar space. As well as being the first mission to return samples from a comet, Stardust was the first sample return mission from the Galaxy!
Before its encounter with the comet Wild2 in January 2004, the Stardust spacecraft raised its collector two times into the interstellar dust stream. Stardust collected a few dozen interstellar dust particles during this time. Nobody knows what the typical interstellar dust grain looks like. This is the very first sample of solid material from the local interstellar medium ever to be returned to Earth for analysis. The challenge is to find them in the aerogel collectors. We expect that the best way to find these particles is by searching using the human eye. Your participation is absolutely critical to the success of this project.
Stardust Mission websites
For more information on the Stardust mission itself, and what has been learned from the cometary dust collected by Stardust, please visit these websites: