Stardust@Home Update from Andrew Westphal

Episode Summary

Executive Summary: This Planetary Radio episode centers on the Stardust at Home project, where tens of thousands of volunteers help identify possible interstellar dust in Stardust’s aerogel collector, and on what comes next: extracting and analyzing those microscopic samples. The show also covers Europa’s habitability, current space news, and Bruce Betts’ skywatching update with meteor showers, planets, and a trivia contest.

Main Topics: Stardust at Home progress: Andrew Westphal reports major progress scanning the Stardust interstellar collector and using trained volunteers to spot candidate particles in high-resolution imagery. Citizen science as 'wetware' computing: The program explains how Stardust at Home differs from SETI@Home: instead of spare computer cycles, it relies on human pattern recognition after tutorials and testing. Extraction and analysis of interstellar samples: Westphal describes the difficulty of removing micron-sized particles without losing trajectory information and outlines the use of synchrotrons and spectroscopy to analyze them. Europa and the possibility of life: Emily Loctawala answers how life might survive on Europa, emphasizing a buried ocean, hydrothermal-vent-like chemistry, and the challenge of radiation and contamination. Current space news and mission updates: Brief headlines include Atlantis’ approved launch to the ISS, Spirit rover recovery after getting stuck in dust, and reports of lightning on Venus. Night sky guidance and trivia: Bruce Betts previews the Geminid meteor shower, Mars, Venus, Saturn, Comet Holmes, and a new trivia contest about the longest gap between spaceflights.

Key Arguments: Crowdsourcing human visual processing can outperform computers for some tasks; Stardust at Home volunteers are highly effective at identifying dust tracks. The interstellar particles cannot simply be removed from the aerogel before extraction because their tracks preserve critical trajectory information. Micron-scale samples require extremely careful handling and non-destructive analysis using advanced lab tools such as synchrotrons and X-ray fluorescence. Europa’s surface is hostile, but its likely internal ocean, geothermal activity, and ice shielding make it one of the most plausible places for life beyond Earth. For Europa, the safest near-term search strategy is to study the surface for chemical byproducts rather than drill into the ocean and risk contamination.

Data Points: Stardust interstellar collector scanned: about one-third - Progress on scanning the collector aboard Stardust Volunteers participating: 23,000 people - Worldwide participants in Stardust at Home Searches completed: more than 40 million - Volunteer searches on imagery from the collector Countries represented: about 57 countries - Geographic spread of Stardust at Home participants Particle size: a few microns across - Tracks/particles being searched for and extracted Sample candidates: several dozen - Potential particles now considered interesting enough to extract and analyze Cost to replace sample: more than $200 million - Westphal emphasizes the preciousness of the collector/sample Geminid meteor rate: 60 to 100 meteors per hour - Bruce Betts’ skywatching forecast for the peak on December 14 Launch date: December 6 - NASA go-ahead for Atlantis launch to the ISS Space shuttle crew: 7 astronauts - Atlantis commander Steve Frick and six crewmates Spacewalks required: at least 3 - Installation of the European Space Agency’s Columbus Laboratory Mars rover problem duration: a few frightening days - Spirit was stuck in a dust-filled crater but recovered Solar system distance: more than five times farther from the Sun than Earth - Europa/Jupiter system temperature and energy constraints

Pivotal Quotes: "we've scanned now about one-third of the interstellar collector on the Stardust spacecraft, and about 23,000 people have done more than 40 million searches" — Andrew Westphal: Describing the scale and success of Stardust at Home "we rely on the incredible image processing capability of the human brain" — Andrew Westphal: Explaining why the project uses human pattern recognition instead of ordinary distributed computing "The Jupiter system does not seem a very likely place to harbor life." — Emily Loctawala: Opening her explanation of Europa’s environmental challenges

Implications: The episode shows citizen science can meaningfully accelerate frontier research, while also highlighting how careful planetary protection and advanced microanalysis will shape future sample-return and astrobiology work.