Explore Mars Underground
Why caves and skylights are the safest on-ramps to life on Mars.
Why caves and skylights are the safest on-ramps to life on Mars.
“We could live in inflatable, aluminum habitats connected by underground tunnels. This would make it easier to travel between the habitats without a spacesuit.”
— Dr. Robert Zubrin, Mars Society (public interview coverage)
Underground (or under-rock) habitats naturally mitigate radiation, micrometeoroids, and thermal extremes, while skylights provide lightwells and access for construction. Lava tubes can host long, modular “green boulevards” with farms, water, and public spaces—scalable cities sheltered by Mars itself.
Skylights are collapse openings into subsurface voids—often ancient lava tubes. On Mars, they’re identified in CTX/HiRISE imagery and cataloged globally. These features are prime candidates for safe, pressurized settlements.
The flanks of Arsia Mons host the iconic “seven sisters” skylights (Dena, Chloë, Wendy, Annie, Abby/Nikki, Jeanne), widely studied as potential cave entrances and lightwells for future habitats.