FAQ

What is Plan R?

Plan R is a design practice specializing in extra-terrestrial habitats, focusing on research, prototyping, and delivery.

How do you innovate?

We combine cutting-edge research with rapid prototyping inspired by leading space agencies to create practical habitat solutions.

Who are your partners?

We collaborate with aerospace experts, engineers, and scientists to ensure our designs meet real-world space exploration challenges.

Can I visit your lab?

Currently, our facilities are closed to the public to maintain focus on research and development projects.

How to contact you?

Reach out via our website contact form or email for inquiries about collaborations or project details.

Innovating Space Habitats

Plan r pioneers design and rapid prototyping of extra-terrestrial habitats, blending cutting-edge research with practical solutions.

From Caves to Cosmos: Why Humanity’s First Homes Beyond Earth Will Be Underground

When our early ancestors roamed the Earth hundreds of thousands of years ago, survival was precarious. Without permanent structures, early hominids sought shelter in caves. These ready-made environments provided safety from predators, protection from the elements, and a place where fire, tools, and community could take root. It was a pragmatic solution: why expend energy building shelters when nature had already done the work?

Fast-forward to today, and humanity faces a parallel challenge as it looks to expand into space. On the Moon and Mars, the conditions are even more hostile than Ice Age Earth. Radiation, micrometeorite bombardment, and extreme temperature shifts create an environment where surface habitats are costly and dangerous. But just as caves provided a shortcut for early humans, natural structures—lunar lava tubes and Martian caves—may once again serve as humanity’s first homes in a new frontier.

The Mass Problem in Space

Building habitats in space is not just an engineering puzzle—it’s a logistics nightmare. Every kilogram launched from Earth costs thousands of dollars. For the Artemis program or future Mars missions, this creates a bottleneck: transporting enough shielding, structural material, and life-support infrastructure to build large, safe settlements is prohibitively expensive.

Radiation shielding alone illustrates the issue. To keep astronauts safe, surface habitats need at least 2–3 meters of lunar regolith piled on top. Transporting that material—or the heavy equipment to move it—is infeasible at scale. Similarly, structures exposed to the raw vacuum and temperature swings must be heavily engineered.

This is where the “cave logic” comes back into play. Just as nomadic hominids avoided building when they could repurpose caves, space settlers can dramatically reduce launch mass by adapting natural underground structures instead of constructing everything from scratch.

Lunar Lava Tubes and Martian Caves

Evidence from orbiters suggests that both the Moon and Mars host vast cave systems. Lava tubes on the Moon may extend for kilometers, with ceilings strong enough to support entire colonies. On Mars, pit craters and collapsed skylights reveal possible entrances to caves that could be linked to ancient volcanic activity.

These underground voids provide three critical advantages:

  1. Radiation Shielding – Just meters of rock overhead block cosmic radiation and solar particle events.

  2. Thermal Stability – Underground environments stay relatively constant in temperature, unlike the brutal day/night extremes on the surface.

  3. Micrometeorite Protection – The natural roof absorbs impacts that would destroy fragile surface structures.

By moving inside, settlers could save thousands of tons of mass otherwise required for shielding and reinforcement.

On-Site Utilization: Building on What’s There

Early cave dwellers did not simply huddle in natural chambers—they adapted them. Fire pits, stone walls, and carvings modified caves into habitable spaces. Likewise, on the Moon and Mars, natural shelters will need augmentation:

  • Inflatable Seals and Doors: To pressurize and isolate cave sections, lightweight inflatable barriers could be deployed at entrances.

  • Modular Habitats: Prefabricated living modules could be placed inside caves, benefiting from natural shielding without the need for thick walls.

  • In-Situ Materials: Regolith can be 3D printed into partitions, platforms, or even floors, reducing dependence on Earth shipments.

  • Robotics First: Autonomous robots could scout, scan, and prepare caves before humans arrive, laying cables, deploying seals, and mapping safe areas.

This hybrid approach—leveraging both natural structures and lightweight add-ons—mirrors the way our ancestors modified caves rather than replacing them.

Strategic Benefits
  1. Mass Reduction: By skipping artificial shielding and foundations, initial missions reduce launch loads drastically.

  2. Scalability: Lava tubes are enormous compared to landers or prefabricated domes. A base could expand into a true settlement without massive new launches.

  3. Scientific Payoff: Caves and lava tubes may preserve unique geological records, or even traces of water and organics, making them valuable research sites.

  4. Earth Applications: Lessons in adapting underground environments can be applied to terrestrial farming, resilience shelters, and disaster response.

Lessons from the Deep Past

Humanity’s story is one of leveraging the environment to overcome limitations. Caves were not permanent homes for all groups, but they offered stepping stones toward stability. They bought our ancestors time and safety, enabling culture and technology to grow.

In much the same way, caves on the Moon and Mars may not represent humanity’s final form of settlement—but they could be the bridge that allows us to establish a foothold beyond Earth. By reducing the need to transport mass, using on-site resources, and working with the planet’s geology rather than against it, we honor the pragmatic instincts of our ancestors.

Conclusion: Caves Then, Caves Now

At Plan R, we believe the future of human settlement in space begins where our story on Earth once did—underground. Just as early hominids used caves to survive and thrive, we see lunar lava tubes and Martian caverns as the natural foundation for building safe, scalable habitats. These environments reduce the need to launch excessive mass, provide inherent protection against radiation and impact, and open up vast spaces for human life and research.

Our mission is to design and deliver the next generation of inflatable, modular, and robotic-assisted habitats that adapt to these natural structures. By combining lightweight technologies with on-site resources, we aim to create resilient sanctuaries that support not only survival, but sustainable growth for future explorers and settlers.

Plan R is committed to turning humanity’s oldest survival strategy into its boldest step forward: transforming the caves of the Moon and Mars into the homes of tomorrow.

Our Location

Plan R operates from a state-of-the-art facility designed for innovation in extra-terrestrial habitat design and rapid prototyping.

Address

London N11 2LG

Hours

Mon-Fri 9-5

Get in Touch

Reach out to plan r for innovative design solutions in extra-terrestrial habitats and cutting-edge research collaborations.

Contact

+44 7773321484

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