Artemis II Radiation Risks and the Minimum Viable Scale in Fossil-Fuel Decline

In this Science Magazine podcast, freelance science journalist Ailey Dolgan discusses the radiation risks astronauts face once beyond Earth's magnetosphere and the protective measures for Artemis II, including storm shelters and novel shielding concepts. The episode also covers a policy-focused look at decarbonizing energy systems, modeling choke points in fossil-fuel networks, and the idea of minimum viable scale as a key constraint on planning when systems shrink.

Artemis II: Deep-space radiation risks and crew protection

The podcast opens with the Artemis II mission, which could launch as soon as February, sending four crew members around the Moon—the farthest humans will travel from Earth. The discussion centers on radiation risks in deep space, including galactic cosmic rays, solar storms, and the waning protection of the magnetosphere as distance from Earth increases. The guest emphasizes that while low Earth orbit has substantial shielding, venturing far from Earth exposes astronauts to persistent, high-energy particles that can affect vision, bones, and overall health. Apollo astronauts provide historical context, but their small sample size and biased health outcomes underline the need for careful planning for longer missions.

"radiation risk" - Ailey Dolgan, freelance science journalist

Engineering solutions: shielding, storm shelters, and personal protection

The разговор moves to protective strategies, highlighting the spacecraft design's storm shelter, a space under the floor that offers a few dozen minutes of protection during solar events. The crew, including a tall Canadian astronaut candidate, would cluster in this area, with gear providing additional shielding. Beyond bulk shielding, researchers are exploring personal shielding options, such as hydrogen-rich protective vests that can be worn during critical tasks outside the storm shelter. The team even recounts a test using two mannequins on Artemis I to compare a vest against no vest, showing measurable differences in radiation exposure.

"storm shelter... crawl into a space under the floor, about the size of a car trunk" - Ailey Dolgan

Biology and biotechnology strategies for radiation resilience

The discussion then turns to biology-inspired approaches, including tardigrades that survive extreme desiccation and radiation through specialized proteins. Scientists are exploring DSU, the damage suppressor protein, and exploring ways to make this protection work in humans, including transient expression via mRNA delivery. While such interventions show protective effects in cells and animal models, there are concerns about unintended consequences, such as potential neuronal damage or interference with normal DNA processes. The conversation also covers alternative biological strategies and the risks of deploying biology at scale across the entire body.

"damage suppressor protein, DSU" - Ailey Dolgan

Avatar chips, onboard biology experiments, and personalized medicine

On Artemis II itself, the Avatar project will send bone-marrow organ-on-a-chip devices to space, seeded with astronauts' blood cells to model stress and aging under space radiation. Each astronaut will have two chips—one on Earth and one in space—enabling a twin-like comparison to identify molecular markers of damage and mitochondrial dysfunction. The goal is to validate chips as stand-ins for real tissue, paving the way for space-based medical decision kits and satellite diagnostics that could tailor antioxidant or targeted drug regimens for individual crew members.

"Avatar avatars as stand-ins for the astronauts" - Ailey Dolgan

From fossil fuels to zero emissions: modeling the fall and minimum viable scale

The second major segment shifts from space to Earth, focusing on modeling the decline of fossil-fuel networks as economies decarbonize. Emily Grubert and Joshua Lappin discuss why fossil systems require deliberate planning rather than relying on natural decline. The conversation highlights risks such as price surges, potential service gaps, and the essential challenge of ensuring energy access during transitions. A central concept introduced is minimum viable scale, a framework that groups physical, economic, and managerial constraints that cause systems to shrink nonlinearly and become unworkable below a certain threshold. The authors argue that current models often miss these non-linear thresholds and underappreciate the need for coordinated management, especially given antitrust and private ownership dynamics that hinder planning. The episode also touches on concrete examples like coal mining in Wyoming and the interdependence of mines, pipelines, and gas stations, illustrating how a few closures can cascade through the network.

"Minimum viable scale is The category that we've offered here to unite a variety of different limits that emerge in complex networked systems" - Emily Grubert

Policy, data, and the path forward

Finally, the authors discuss barriers to integrating minimum viable scale into policy and regulation, focusing on market structure, data access, and the potential role for public management in critical infrastructure. They emphasize that, as systems shrink, the ability to coordinate and maintain essential services becomes more fragile, and the costs and safety risks grow. The piece closes on an optimistic note that nationalized or publicly coordinated energy sectors have been implemented elsewhere, suggesting a path to more resilient, transparent planning in the United States and beyond. The speakers stress that existing systems provide a valuable information base for modeling, but obtaining detailed performance data remains a hurdle due to confidentiality and market competition.

"Minimum viable scale... unite a variety of different limits" - Emily Grubert