Planetary Astronomer Franck Marchis

Episode Summary

Executive Summary: This Planetary Radio episode blends live museum banter, Planetary Society updates, and a substantive interview with astronomer Frank Marshes on multiple asteroid systems, adaptive optics, and future mission concepts. Bill Nye also urges support for NASA planetary exploration funding, while Bruce Betts closes with skywatching, trivia, and audience participation from the National Air and Space Museum.

Main Topics: Planetary Society website and mission updates: Emily Lakdawalla previews the new Planetary Society website, expanded blogging, Cassini imagery, Mars rover progress, and a 3D Lunar Reconnaissance Orbiter crater view. Advocacy for planetary science funding: Bill Nye describes lobbying Congress to restore the NASA planetary science budget line and emphasizes the scientific and civilizational importance of exploration. Frank Marshes on multiple asteroid systems: Marshes explains how binary and trinary asteroid systems are found and studied with adaptive optics, and why they matter for understanding solar system formation. Adaptive optics and next-generation observatories: The interview highlights how AO improves ground-based imaging, the promise of seeing in visible light, and future systems such as the ELT and GPI for exoplanet work. Future spacecraft missions to asteroid systems: Marshes argues for an orbital mission to visit diverse asteroid system types in order to test formation theories more directly. Live 'What's Up' segment and trivia: Bruce Betts provides night-sky targets, random space facts, and museum-focused trivia questions with audience participation.

Key Arguments: The new Planetary Society website makes it easier to showcase more voices and multimedia content, not just the main blog feed. Cassini imagery remains scientifically and visually valuable, but upcoming Titan flybys will reduce icy-moon encounters as the spacecraft exits the ring plane. Planetary science needs restored funding because missions like Cassini and Curiosity are producing transformative discoveries and may help detect life. Multiple asteroid systems are not anomalies; about 200 companions are known, making them a rich laboratory for solar system archaeology. Asteroids preserve early solar system conditions because terrestrial planets and giant-planet cores formed from similar building blocks. Adaptive optics is now mature enough to support serious solar-system science and will soon extend to exoplanet characterization. A dedicated spacecraft mission to visit several asteroid-system types would advance the field beyond remote sensing alone. Ground-based telescopes with improved AO and larger apertures are crucial until direct mission access becomes possible.

Data Points: Planetary science budget line item: $309 million - Bill Nye says Congress should restore this NASA budget line dedicated to planetary exploration missions. Known multiple asteroid companions: 200 - Frank Marshes cites the number of known asteroid companions discovered so far. Triple asteroid system example: 87 Sylvia - Marshes identifies Sylvia as the first trinary system he helped discover. Size of Sylvia primary: ~200 km - He describes 87 Sylvia as a large primary body with two tiny moons. Size of Sylvia moons: ~7 km each - Marshes estimates Romulus and Remus at about seven kilometers across. Fraction of near-Earth and inner-main-belt asteroids: 10-15% - He says this share may be binaries or extremely elongated bodies shaped by the YORP effect. Apollo-Soyuz year: mid-1970s - Bruce Betts references the Apollo-Soyuz Test Project and its pressure-airlock issue. Cassini timeline: end of month flyby of Titan - Emily notes Cassini would perform a Titan gravity assist and leave the ring plane soon. GPI first light: end of 2012 - Marshes says the Gemini Planet Imager was expected to have first light then, if all goes well. Exoplanet spectra timing: 2013 - He predicts images or spectra of exoplanets should begin appearing in 2013.

Pivotal Quotes: "NASA's budget is a step in the wrong direction for planetary science." — Andy Chaikin (referenced by Emily Lakdawalla): Emily explains why Chaikin made and shared a video advocating for planetary science funding. "We're fighting the good fight, Matt. This is the kind of thing that great civilizations do, isn't it?" — Bill Nye: Bill Nye discusses lobbying Congress to restore the planetary science budget line. "We are archaeologists, in Space." — Frank Marshes: Marshes explains why asteroids preserve evidence of solar system origins.

Implications: Listeners are reminded that planetary science depends on public advocacy, persistent observing technology, and future missions. The episode points toward richer exoplanet and asteroid science through adaptive optics, larger telescopes, and targeted spacecraft.