Field Test: Planetary Deep Drill

Episode Summary

Executive Summary: This episode of Planetary Radio covers a successful deep-drilling field test in a California gypsum quarry as a prototype for future Mars, Europa, and icy-moon exploration, plus updates on Rosetta’s comet images and Akatsuki’s hard-won Venus orbit insertion. It also includes a weekly skywatch, space history, trivia, and a special relativity feature about how time changes with speed and gravity.

Main Topics: Planetary Deep Drill field test in California: Matt Kaplan reports from a U.S. Gypsum quarry near the Salton Sea, where Honeybee Robotics is testing a drill designed to penetrate deep below the surfaces of Mars- and ice-moon-like environments. Rosetta and comet 67P image release: Emily Lakdawalla discusses ESA’s first released OSIRIS images of comet 67P/Churyumov-Gerasimenko taken after rendezvous, along with a plan to release a new image per day. Akatsuki successfully enters Venus orbit: The show highlights Japan’s Akatsuki spacecraft finally reaching Venus orbit after years of recovery, and the enthusiastic fan support that helped sustain public interest. What’s Up: skywatch, meteor shower, and lunar history: Bruce Betts covers visible planets, the Geminid meteor shower, and the anniversary of Apollo 17, the last crewed lunar landing. Trivia and planetary geology: A listener contest revisits Iapetus and asks about sand dunes on other worlds, connecting planetary science to familiar desert geology. Special relativity mini-feature: A produced segment explains how Einstein’s relativity changes our understanding of time, using a dog, an astronaut, and a black hole as examples.

Key Arguments: A physical drill is a practical alternative to melt probes for icy worlds because extremely cold ice, especially on Europa, makes melting-based approaches difficult. The drill’s in-borehole instruments embody a paradigm shift: bringing an instrument to the sample rather than bringing the sample to the instrument. Gypsum is a useful Earth analog for ice and sulfate-rich planetary materials, making the Salton Sea quarry a strong test site. The Planetary Deep Drill already exceeded its previous Earth depth record and showed strong reliability, suggesting readiness for more ambitious deployments. Akatsuki’s public outreach on Twitter helped maintain support during its long Venus recovery, showing how fan communities can sustain missions. Special relativity means that motion and gravity affect time, though the measurable effects are tiny at everyday scales and only become significant for fast spacecraft or extreme gravity.

Data Points: Depth drilled: 13.8 meters and climbing - Chris Sackney says the prototype had already surpassed the previous record during the field test. Previous record depth: Around 10 meters - Referenced as the prior best depth for the drill before this test. Target depth for the test: Around 20 meters - Planned completion of the field test before Christmas. Drilling rate: 1 to 2 meters per day - Described during the test as the achieved rate at the quarry. Power required by drill: 200 to 250 watts - Estimated electrical demand for drilling operations. Curiosity RTG continuous power: Around 100 watts - Used to argue the rover power system could support the drill via batteries. Curiosity-scale adaptation: About 2.5 meters - Projected miniaturized drill size suitable for a Curiosity-class rover. Greenland test timeline: Spring 2017 - Planned next engineering run after the California field test. Greenland depth goal: About 100 meters - Future planned drilling in ice during Greenland tests. Akatsuki nominal mission length: Two years - Japan’s Venus mission science phase after shakedown. Akatsuki shakedown period: About three months - Time needed to check spacecraft and instruments before full science operations. Space Shuttle speed: 17,500 miles per hour - Tom Jones used this to illustrate special-relativistic time dilation. Time offset from shuttle flights: About 3 milliseconds - Tom Jones estimated how far behind the rest of humanity he fell during 53 days in orbit. Apollo 17 year: 1972 - Marked as the last time humans walked on the Moon. Geminid shower peak: December 13-14 - Bruce Betts notes the shower had just peaked at the time of recording. Contest deadline: Tuesday, December 22, 8 a.m. Pacific Time - Deadline for listeners to submit the sand dune trivia answer.

Pivotal Quotes: "We have to bring an instrument to that sample itself." — Chris Sackney: Explaining the conceptual shift behind the Planetary Deep Drill approach. "It looks like I fell behind the rest of the human race by about three milliseconds." — Tom Jones: Describing the relativistic effect of multiple shuttle flights. "Time is malleable. It’s elastic. It’s squishy." — Laura Danley: Introducing the basic idea of relativity in the special feature.

Implications: The episode points to credible near-future tools for exploring subsurface environments on Mars and icy moons, while reinforcing how outreach, engineering tests, and public enthusiasm can sustain long-horizon planetary missions.