Our Mysterious Sister: Venus

Episode Summary

Executive Summary: This Planetary Radio episode spans three major themes: a new crowdsourced "Space Goals" project for space enthusiasts, a retrospective on Apollo 12’s dramatic launch and pinpoint lunar landing, and an in-depth conversation with Javier Peralta about Venus’s mysterious atmosphere, superrotation, and polar vortices. The show closes with Bruce Betts’s skywatching notes, trivia, and listener contest results.

Main Topics: Space Goals crowdsourced project: Kate Howells explains a new Planetary Society initiative to catalog and crowdsource space experiences, from simple backyard observations to once-in-a-lifetime adventures, inspired by birdwatching life lists. Apollo 12 50th anniversary tribute: Jason Davis reviews Apollo 12’s lightning strike during launch, the recovery via "SCE to OX," and the mission’s successful pinpoint landing near Surveyor 3, showing how Apollo 12 validated techniques needed for future lunar missions. Venus atmosphere and Akatsuki science: Javier Peralta discusses new understanding of Venus’s atmosphere from Galileo, Venus Express, and Akatsuki, including three-dimensional cloud tracking, variable albedo, and the role of solar tides in superrotation. Mysteries of Venus’s clouds and absorber: Peralta describes the long-standing unknown UV-absorbing material in Venus’s upper clouds, the possibility of exotic chemistry or even microbial life, and the need for in-situ sampling to solve it. Venus polar vortex and cloud dynamics: The interview explores Venus’s dramatic polar vortices, their changing shapes, possible chaos in their motion, and evidence that their structure may extend across altitudes and connect the two poles. What's Up: transit, skywatching, trivia: Bruce Betts previews the Mercury transit, notes Venus’s return to the evening sky, recounts the first food eaten in space, and sets a new trivia question about the first Saturn V launch.

Key Arguments: Crowdsourcing space experiences can help people discover, track, and share meaningful ways to engage with astronomy and exploration. Apollo 12 mattered not because it was first, but because it demonstrated precision lunar landing and operational resilience after a lightning strike. Venus remains scientifically compelling because its atmosphere is dynamic, poorly understood, and driven by processes that may link solar forcing to superrotation. Multispacecraft comparisons between Venus Express and Akatsuki have improved understanding of Venus’s changing cloud albedo and winds. The mysterious UV absorber in Venus’s clouds remains unresolved and may require future probes or sample-return-like atmospheric measurements. Venus polar vortices are not simple stable structures; they change shape rapidly and may differ across cloud layers, implying complex three-dimensional circulation. Future Venus exploration should prioritize missions that can penetrate below the clouds, with balloons and descent probes seen as especially valuable.

Data Points: Mercury transit date: November 11 - Bruce Betts announces a rare transit of Mercury across the Sun. Mercury transit start/end (UTC): 12:35 UTC to 18:04 UTC - Timing given for the 2019 Mercury transit. Mercury transit next occurrence: 2032 - Bruce notes the next transit after this one will not occur until 2032. Apollo 12 launch date: November 14, 1969 - Jason Davis introduces the 50th anniversary of Apollo 12. Lightning strikes during Apollo 12 ascent: 2 - The Saturn V was struck twice during launch. Distance from intended Apollo 12 landing site to Surveyor 3: about 160 meters - Apollo 12 landed very close to the target Surveyor 3 spacecraft. Surveyor 1 / Surveyor 3 recovery effort: 1967 - Ewan Whitaker helped locate Surveyor 3 after earlier work on Surveyor 1. Venus superrotation wind speed: 300 km/h (200 mph) - Describes winds in Venus’s atmosphere much faster than the planet’s rotation. Upper cloud altitude on Venus: about 70 km above the surface - Location of the cloud tops and UV absorber region. Lower cloud altitude referenced: about 50 km - Used when discussing vertical differences in the polar vortex. Akatsuki orbit insertion: December 2015 - Peralta identifies the date of the first major Akatsuki observation image. Akatsuki mission orbit around Venus: about every 10 Earth days - The spacecraft’s current orbital cycle is mentioned at the end. Venus Express / Akatsuki comparative timespan: last 10 years - A study compared UV albedo variations over roughly a decade. Planetary Goals submission limit: up to 3 per form - Kate Howells explains how many ideas can be submitted at once, though the form may be reused.

Pivotal Quotes: "Try SCE to OX." — Jason Davis: The famous command that helped Apollo 12 recover after lightning disrupted the spacecraft during ascent. "There is no easy way to call it." — Javier Peralta: Peralta discussing the mysterious UV-absorbing material in Venus’s upper clouds. "We are trying to figure out one of the key points that is to know how this super rotation is fed." — Javier Peralta: On the central unresolved question of what powers Venus’s rapid atmospheric superrotation.

Implications: Listeners are invited to participate directly in Planetary Society projects, while the Venus segment underscores that future missions—especially probes, balloons, and atmospheric samplers—are needed to resolve major open questions about Venus’s climate and habitability.