Smashing Holes in Mars to Look for Life

Episode Summary

Executive Summary: This Planetary Radio episode covered three major space topics: Rosetta/Philae’s landing-site selection on Comet 67P, NASA’s commercial crew award decision among Boeing, SpaceX, and Sierra Nevada, and Explore Mars’ ExoLance concept for probing Mars for extant life with penetrators. The show closed with Bruce Betts’ skywatching update, a space history note, and a contest segment.

Main Topics: Philae landing site selection on Comet 67P: Emily Lakdawalla explains how Rosetta’s NavCam images are used to evaluate five candidate landing ellipses for the Philae lander, emphasizing terrain safety, slope, boulders, and the lander’s unguided descent. She also describes the CONCERT radio experiment that will sound the comet’s interior. NASA commercial crew funding and contractor competition: Bill Nye discusses the imminent NASA decision on commercial crew funding, noting that Boeing, SpaceX, and Sierra Nevada are competing and that more competition should improve access to low Earth orbit. He contrasts the companies’ likely responses if NASA funding disappears. ExoLance and the search for current life on Mars: Chris Carberry describes Explore Mars’ ExoLance project, which seeks to use small penetrators to reach 1–3 meters below the Martian surface to look for extant life and potentially other subsurface science payloads. Explore Mars as a focused advocacy and project-driven nonprofit: Carberry outlines Explore Mars’ origins as a project-oriented nonprofit focused on policy, STEM education, conferences, and technical initiatives rather than membership growth, including collaboration with the Planetary Society on advocacy efforts. Skywatching, space history, and listener contest: Bruce Betts provides the night-sky update for Mars, Saturn, Venus, Jupiter, and Regulus, mentions Viking 2 and Voyager 1 in space history, and handles the weekly contest about the Apollo 17 pocket mice and a new solar-system location challenge.

Key Arguments: The Philae lander must target a safe, relatively flat area because it will not be guided during descent; comet geometry and local gravity make landing risk the central constraint. Rosetta’s NavCam images are especially useful for landing-site selection because they show the whole comet, while higher-resolution OSIRIS images are not as broadly shared. Philae’s CONCERT instrument matters because transmitting radio signals through the comet will reveal its internal structure. In commercial crew, competition among Boeing, SpaceX, and Sierra Nevada is valuable because multiple providers increase resilience and lower-cost access to orbit. SpaceX is likely to keep developing regardless of NASA’s decision, while Boeing may pivot away if it does not win further funding. ExoLance is motivated by the absence of life-detection experiments in the 2020 rover plans and by the scientific belief that any current Martian life would likely survive below the radiation-sterilized surface. Penetrators offer an efficient way to sample multiple Martian locations in one mission, unlike a single drill point, and could potentially host additional payloads beyond biology experiments. Explore Mars sees itself as a nimble organization combining advocacy, education, and technical development rather than a traditional membership society.

Data Points: Comet landing sites: 5 candidate ellipses - Rosetta identified five possible landing sites for the Philae lander. Surface penetration target: 1 to 3 meters below the surface - Carberry said experts believe extant life on Mars would likely be buried this deep. Penetrators per mission: up to 6 - ExoLance aims to deploy as many as six small penetrators on a mission. Fundraising goal: $250,000 minimum - Indiegogo campaign target to build and test Earth-based penetrator prototypes. Campaign duration: until the end of September - ExoLance crowdfunding effort timeframe. Commercial crew funding: better part of a billion dollars - Bill Nye described the NASA money already distributed among companies. Number of companies: 3 - Boeing, Sierra Nevada, and SpaceX are the major commercial crew competitors. Mars/space history years: 1976 and 1977 - Bruce Betts noted Viking 2 landed on Mars in 1976 and Voyager 1 launched in 1977. Venus-Regulus separation: 1 degree - Betts said Venus would be one degree from Regulus on September 5. Andromeda Galaxy apparent width: about 6 times wider than the Moon - Betts’ random space fact about the visible extent of Andromeda. Apollo 17 mice: 5 pocket mice - Contest question referenced five pocket mice flown on Apollo 17.

Pivotal Quotes: "once they let it go, it's going to drop wherever it's going to drop." — Emily Lakdawalla: Explaining why Philae landing-site selection must prioritize terrain safety because the lander is not guided during descent. "I feel that the more competition there is, the more rides into lower orbit, the better it is for humankind." — Bill Nye: His argument for preserving multiple commercial crew providers. "if life currently exists on Mars, it's going to be at least one to three meters below the surface" — Chris Carberry: The core rationale for ExoLance penetrators targeting subsurface exploration.

Implications: The episode highlights a shift toward risk-managed planetary landings, commercial competition in human spaceflight, and low-cost innovation for astrobiology. If these efforts succeed, they could improve deep-surface science on Mars and expand access to orbit.