Microscopic dust particles that could date back to the very start of our solar system have been extracted from NASA‘s Stardust spacecraft payload, promising to be the first contemporary samples of interstellar dust. Stardust returned its collection of stellar detritus back in 2006, and thus began a painstaking sift through the particles to see what goodies had been gathered during the three billion mile journey.
Stardust had some unusual equipment to collect those samples, too. Inside its “Sample Return Canister” is a double-sided tray: on one side, there’s silica aerogel, which was used when the craft flew a mere 149 miles away from a comet back in January 2004.
On the other side, interstellar dust particles gathered up over the course of the seven year mission were found.
Actually making sense of them has proved difficult, especially because the particles have proved far more diverse compared to what NASA’s science team predicted, both in terms of structure and chemical composition. Examples range from “fluffy”, snowflake-like larger particles, down to tiny sub-micron wide specks.
NASA turned to crowdsourcing to help identify possible motes of interest, with volunteers known as “Dusters” looking through high-resolution photos of the collection plates and the aluminum foil in-between them to flag up any likely candidates.
Once identified, the Naval Research Laboratory pinpointed the actual samples and shipped them to UC Berkeley for further investigations.
While it’s too soon to say whether the particles identified actually are debris from interstellar space, scientists are hopeful that, should that be the case, they’ll help further understanding of how the universe formed.