Unexplainable — "Why Did We Go Back to the Moon?"

Podcast: Unexplainable
Host: Noam Hassenfeld (Vox)
Guests: Anne McClain (NASA astronaut), Rebecca Boyle (science writer), Jonathan Jiang (NASA astrophysicist), Scott Kelly (former NASA astronaut)
Date: April 13, 2026

Episode Overview

This episode unpacks the motivations, challenges, and scientific mysteries behind humanity’s renewed focus on lunar exploration, specifically through NASA’s Artemis program. The Unexplainable team explores the physiological, technological, and existential questions prompted by the goal of living and working on the Moon—and potentially Mars. Featuring first-hand astronaut experiences and expert commentary, the episode probes both the promise and peril of making space a more permanent home.

Key Discussion Points & Insights

The Artemis Era: Humanity’s Return to the Moon

• Historic Launch: NASA’s Artemis 2 became the first crewed mission to orbit the Moon in over 50 years, advancing further than any prior mission—without landing ([01:05]–[02:30]).
  • “The crew of Artemis 2 now bound for the moon. Humanity's next great voyage begins.” — Noam Hassenfeld [01:22]
• Ultimate Goal: Artemis signals not just a return, but the intent for permanence: “We’re going back to stay.” [02:43]
• Vision for the Future: By 2040, NASA envisages a lunar base and eventual Mars missions, taking steps toward a multi-planetary future ([03:12]–[03:39]).

The Brutal Reality of Space for Humans

• Space is Hostile:
  • “Space is terrible. It wants to kill us.” — Rebecca Boyle [03:50]
  • Danger comes from weightlessness, radiation, isolation, and microgravity.
• Life in Orbit vs Deep Space:
  • Experience in low Earth orbit (ISS) has given us a glimpse, but only 28 people have been beyond 1,000 miles from Earth ([04:39]).
  • Apollo missions lasted mere days—far shorter than what a moon base would require ([05:02]).
• Astronaut Anne McClain on Living in Space:
  • Describes awe and psychological shock when first entering space ([06:16]–[07:06]).
  • “It’s really hard to describe … there just hasn't been anything like it before.” — Anne McClain [06:23]
• Radiation Experiences:
  • Astronauts see “shooting stars” with their eyes closed—likely radiation particles hitting their retinas ([07:41]–[08:07]).
    • “If little atoms became bullets.” — Anne McClain [07:41]
  • Even with Earth's protective magnetic field, exposure is significant; outside that field, risks multiply ([09:53], [10:53]).

Physiological Challenges

• Impact of Microgravity:
  • Fluid shifts, changes to eyesight, diminished bone density; astronauts’ height increases in space, reverting (painfully) on return ([08:25]–[09:23]).
    • “I grew just under 2 inches in space … I shrunk right back down.” — Anne McClain [09:10], [09:23]
• Psychological Effects: “Space fog” and chronic fatigue are common; long-term cognitive and physical impacts linger even after landing ([09:33]–[09:47]).
• Danger Escalates Beyond Orbit: Apollo astronauts, exposed to more radiation, saw higher rates of heart disease ([10:53]–[11:32]).

Lunar Challenges: Beyond the ISS

• Gravity & Disorientation: The Moon’s gravity is just high enough to confuse the human vestibular system, causing frequent astronaut tumbles ([12:10]–[12:42]).
  • “I look like an elephant stumbling around here.” — Apollo astronaut [12:39]
• Lunar Night: Two weeks of darkness and frigid cold, extreme even for adaptable tech ([12:47]–[13:08]).
• Moon Dust—The Ubiquitous Threat:
  • Sharp, abrasive, pervasive: gets everywhere, is inhaled, and causes illness ([13:17]–[14:56]).
    • “Every piece of moon dust is jagged and sharp. So it’s just flying like bullets all over the place.” — Rebecca Boyle [14:12]
    • “I think Dust is probably one of our greatest inhibitors to a nominal operation on the moon.” — Gene Cernan, Apollo 17 astronaut [14:56]
• Long-Term Health Risks: Prolonged exposure may increase risks of cancer, respiratory illness, and shortened lifespans ([15:14]).

Technological and Survival Innovations

• Possible Solutions:
  • Medications to counter microgravity effects, plastics for radiation protection in suits, coatings to repel lunar dust ([16:09]).
  • Lunar Caves: Using ancient lava-tube caves for shelter—constant temperature, protection from radiation and dust ([16:34]–[17:06]).
    • “A moon base in a lunar cave … it's a fantastic thing to imagine.” — Noam Hassenfeld [17:37]

Existential Questions: Why Bother?

• The Fundamental Question: Is risking human life to live in space worth it? ([18:18])
  • “I mean, that’s kind of the million dollar question for a lot of these programs: what’s the point?” — Rebecca Boyle [18:18]
• Existential Risk: Jonathan Jiang (NASA) frames multi-planetary expansion as vital to the long-term survival of life ([22:20]–[23:28]):
  • “Suppose we are alone and we are precious. If we are destroyed, it means the life in the universe was gone.” — Jonathan Jiang [22:34]
• Geopolitical Motivation: With China’s lunar ambitions, urgency and competition drive some of the mission ([21:18]–[22:20]).

Other Benefits of Space Exploration

• Spinoff Technologies: Solutions developed for space (e.g., camera technology, medical advances) have everyday benefits ([24:59]–[25:14]).
• Scientific Research: Human intuition and flexibility surpass robots; famous example: "seatbelt basalt" discovered on Apollo 15 only because of human improvisation ([25:30]–[27:34]).
  • “When you put a person in a situation, they have the ability to look off to the side and go, hey, what was that?” — Anne McClain [25:36]

Would You Go?

• Different Perspectives:
  • Jonathan Jiang: “I think many people like me, we are not afraid of even death. We would like to explore, to find something new.” [28:05]
    • He’d go to Mars—one way—if his daughter would join him [28:12].
  • Anne McClain: “Responsible exploration means that it’s a two way ticket.” [28:29]
  • Scott Kelly: Not interested in a one-way trip, but jokes he’d “watch that reality show” ([28:50]–[29:13]).
    • “Have you ever read the book The Lord of the Flies? … Probably that kind of interesting.” — Scott Kelly [29:15]
  • Rebecca Boyle: As much as she loves the Moon, the safety risks make a real mission off-limits for her ([29:41]).

Philosophical Reflection

• The Necessity—and Limits—of Expansion:
  • “We have this planet that gave birth to us all … we have a lot to still save here and that we’re made for it. Keeping both of those things in mind keeps us a little bit more feet on the ground, even as we look to the heavens.” — Rebecca Boyle [30:44]
• While humanity is driven to expand, it’s crucial to remember the profound risks of space and the unique gift of Earth ([30:08]–[31:19]).

Notable Quotes & Memorable Moments

• “Space is terrible. It wants to kill us.” — Rebecca Boyle [03:50]
• “The crew of Artemis 2 now bound for the moon. Humanity's next great voyage begins.” — Noam Hassenfeld [01:22]
• "This time we're going back to stay." — Artemis astronaut [02:43]
• “I grew just under 2 inches in space.” — Anne McClain [09:10]
• “If little atoms became bullets.” — Anne McClain (on cosmic radiation) [07:41]
• “I think Dust is probably one of our greatest inhibitors to a nominal operation on the moon.” — Gene Cernan [14:56]
• "Suppose we are alone and we are precious. If we are destroyed, it means the life in the universe was gone." — Jonathan Jiang [22:34]
• "Responsible exploration means that it's a two way ticket." — Anne McClain [28:29]
• "We have this planet that gave birth to us all. ...we have a lot to still save here and that we're made for it." — Rebecca Boyle [30:44]

Timestamps for Key Segments

• [01:05–02:30]: Artemis 2 and humanity’s return to lunar orbit
• [03:50–04:28]: Why space is fundamentally hostile to life
• [06:16–07:06]: Anne McClain’s first launch and sunrise in space
• [07:41–08:07]: Experiencing radiation firsthand on ISS
• [09:10]: The surprising effects of microgravity on the body
• [10:53–11:32]: Greater health risks beyond low Earth orbit
• [12:10–13:08]: Lunar gravity and the difficulties it creates
• [14:56]: Apollo astronauts’ warnings about moon dust
• [16:34–17:06]: Lunar caves as potential future habitats
• [18:18, 22:20]: Philosophical and existential reasons for space colonization
• [25:30–27:34]: The "seatbelt basalt"—a story of human discovery in space
• [28:05–29:41]: Guests share whether they would venture out themselves
• [30:44]: The importance of remembering the value of Earth

Summary

With NASA’s Artemis missions, humanity is taking bold but risky steps toward becoming an interplanetary species. The show thoughtfully explores the scientific, existential, and personal facets of this next chapter—probing why we’re so compelled to go, what it will really take to live beyond Earth, and how the answers might shape not only our future in space but our perspective on life here at home. The episode balances awe and caution, rooting a grand vision for space with both gritty challenges and philosophical humility.