Scientists Found Lava Tubes on the Moon – Humans Could Live There

The Moon is a beautiful place to visitif your idea of “beautiful” includes vacuum, radiation, and a temperature swing that can’t decide whether it’s trying to roast you or cryo-freeze you. For decades, scientists have suspected there’s a workaround hiding in plain sight: go underground. And now, thanks to new analyses of spacecraft data, that “Moon cave” idea has moved from sci-fi set dressing to something that looks a lot like real lunar real estate.

The headline sounds like a dream listing: “Spacious underground tunnel. Natural radiation shielding. No HOA.” But the real story is more interesting (and slightly weirder) than a simple “humans can move in tomorrow.” Scientists have gathered stronger evidence that lunar lava tubeslong, hollow tunnels formed by ancient volcanic activityexist in accessible places, including near the Moon’s famous Sea of Tranquility. If we ever want long-term bases for Artemis-era exploration and beyond, these tubes could be the Moon’s most practical shelter.

What Exactly Is a Lunar Lava Tube (and Why It’s Not Just a Fancy Crack)

A lava tube is basically nature’s version of a subway tunnelbuilt by flowing lava instead of a bored mole with a union job. When molten lava moves under a cooling surface crust, the top can harden while lava continues to stream underneath. If the lava later drains away, it can leave behind an empty conduit: a long, hollow tunnel.

How lava tubes form

On Earth, lava tubes are common in volcanic regions like Hawaiʻi and the American Southwest. They can form when a lava river develops a hardened roof, or when the edges of a lava channel build up and enclose the flow. Over time, the moving lava either diverts or stops, and the remaining hollow space becomes a tube. Some tubes can be modestwalkable caves. Others are huge, branching systems that feel like natural cathedrals made of basalt.

Why the Moon can grow “mega-tubes”

The Moon’s lower gravity and lack of wind or liquid water erosion means structures can remain stable for incredibly long times. In theory, that allows lunar tubes to be larger than many Earth counterparts. A roof that might collapse more easily on Earth can potentially span a wider gap on the Moon. In other words: lunar geology may have accidentally engineered bigger caves than we’re used toexactly the kind that could fit equipment, habitats, and the dreams of every mission architect who’s ever muttered, “We really need a roof up here.”

How Scientists “Found” Them: From Skylights to Radar Echoes

Scientists didn’t spot a giant neon sign that reads “CAVE THIS WAY.” What they found are the kinds of clues geologists love: pits, odd shadows, temperature patterns, gravity quirks, and radar reflections that don’t match solid rock.

The early clue: “skylights” like the Marius Hills pit

One of the most famous lunar cave candidates is the Marius Hills pit, sometimes described as a potential skylighta hole where a lava tube roof may have collapsed. Spacecraft images show a steep-walled opening, with interior shadows that suggest there’s more than just a simple crater. These pits matter because they could be natural entrances to underground spaces without having to drill through meters of rock like you’re installing an interplanetary basement.

Over the years, multiple missions have helped map and photograph these features. High-resolution lunar imagery has revealed numerous pits and collapse features scattered across the Moon, especially in volcanic “mare” regions. Each pit is a question mark: is it a dead-end shaft, or the front door to an underground network?

The big step: radar evidence in Mare Tranquillitatis

In 2024, researchers reported stronger, more direct evidence of an accessible cave conduit below a pit in Mare Tranquillitatisthe Sea of Tranquility, a region made famous by Apollo 11. Instead of relying only on surface photos, they reanalyzed radar data collected by a radar instrument aboard NASA’s Lunar Reconnaissance Orbiter. Using advanced signal processing, they identified reflections consistent with an underground voidan “empty” conduit that fits what you’d expect from a lava tube rather than solid rock.

The shapes inferred from the radar analysis suggest a cave passage that could be tens of meters wide and extend for at least dozens of meters (and possibly much farther). Importantly, this isn’t just “a pit might connect to a cave.” It’s evidence that the cave-like structure itself exists.

Clues from gravity maps and temperature “comfort zones”

Radar isn’t the only detective tool in the lunar toolkit. Gravity mapping missions have helped scientists identify subsurface anomaliesplaces where the density distribution hints at empty spaces or unusual structures. Separately, thermal data has revealed something surprising: some lunar pits and shaded areas can maintain far more stable temperatures than the lunar surface.

On the surface, the Moon can swing from blistering hot in sunlight to brutally cold in darkness. But inside a pitespecially under an overhangtemperatures can remain much steadier, hovering in a “comfortable” range compared to the surface extremes. For future habitats, stable temperatures aren’t just a convenience; they’re engineering gold. Less thermal stress means simpler systems, less energy spent fighting the environment, and fewer materials cracking from constant expansion and contraction.

Why Everyone’s Excited: Lunar Housing That Comes With Free Shielding

If you’re wondering why space agencies care so much about caves, here’s the answer: the Moon is not shy about trying to ruin your day. The surface is exposed to radiation, micrometeorite impacts, and harsh temperature extremes. A lava tube is like a natural bunker.

Radiation: the Moon’s least charming feature

Earth’s magnetic field and atmosphere protect us from a lot of high-energy particles. The Moon has basically… vibes. That means astronauts on the surface face higher exposure to cosmic radiation and solar particle events. Covering habitats with thick regolith helps, but building a shield from scratch is heavy, messy, and complicated.

A lava tube’s roof could provide substantial shielding by default. Put simply: meters of rock between you and space radiation is the kind of “minimalist decor” that mission planners actually love.

Micrometeorites: tiny, fast, and rude

Even small impacts can be dangerous over time because the Moon lacks an atmosphere to burn up incoming debris. A subsurface habitat reduces exposure to constant bombardment. It’s the difference between living under an open sky and living under a sturdy roofexcept the “roof” is lunar basalt that’s been holding its act together for ages.

Temperature stability: the Moon’s underground advantage

A big part of making long-term life-support systems work is controlling temperature. The lunar surface forces you to engineer for extremes. Underground, the environment is more stable. That doesn’t mean it’s automatically cozythere’s still work to dobut it shifts the problem from “survive chaos” to “manage a steady cave climate,” which is a much more pleasant spreadsheet.

Could Humans Actually Live There? The Practical Reality Check

“Could live there” is doing a lot of work in that headline. The better way to say it is: lava tubes could make long-term lunar habitats significantly easierif we solve a set of very real engineering and operational challenges.

How a lava tube habitat might work

You wouldn’t just move into a cave with a sleeping bag and a flashlight like it’s a weekend camping trip. A realistic approach would likely involve:

• Robotic scouting to map the interior, check stability, and identify hazards.
• Sealed habitat modules (rigid or inflatable) placed inside the tube and pressurized.
• Airlocks and dust control at entrances to keep lunar regolith from becoming everyone’s least favorite seasoning.
• Power and communications links routed from the surfacelikely via cables, relays, or a combination of both.

The cave provides shielding and thermal stability, but the life-support environment still has to be built and maintained with the same seriousness as any spacecraft. Think “submarine in a tunnel,” not “glamping.”

Light, schedules, and the psychology of “no windows”

Humans are adaptable, but we’re also the species that invented seasonal depression lamps, so it’s fair to say lighting matters. Living underground means engineers would need strong, reliable lighting systems that support work and sleep cycles. You can’t rely on sunlight streaming in unless your cave includes a well-placed skylight (and even then, dust and geometry have opinions).

The good news: controlled lighting is already part of spacecraft and Antarctic station design. The Moon would simply be the most expensive place we’ve ever installed a circadian-friendly LED system.

Science bonus: the Moon’s underground archive

Lava tubes could be more than sheltersthey could be scientific treasure chests. Underground spaces may preserve layers of lunar volcanic history, protect delicate deposits from space weathering, and provide sites to study how the Moon formed and evolved. A tube near a mare region could offer a cross-section of ancient lava flows like a geological layer cakeexcept the frosting is rock.

The Hard Parts: Turning a Cave Into a Neighborhood

Before we start naming lunar cul-de-sacs, we have to deal with the realities that make “just live in a cave” sound easy in a headline and complicated in a mission plan.

Getting in: entrances are not wheelchair-accessible (yet)

Many candidate entrances are steep pits. That’s a problem for astronauts and a bigger problem for heavy equipment. Future missions may need robotic cranes, tethered descent systems, or purpose-built entrance modifications to move safely between the surface and the tube interior.

This is one reason robotics matter so much: before humans risk a descent, robots can map, test, and verify.

Stability and unknowns: what’s holding up that roof?

Even if a tube has been stable for millions (or billions) of years, you don’t assume it’s safe just because it’s old. Engineers would want to understand roof thickness, fracture patterns, and how the structure might respond to vibration, impacts, and temperature changes. The Moon also experiences moonquakes, and while they’re generally different from Earthquakes, they’re still part of the risk picture.

Mapping the interior: caves hate GPS

Navigation is harder underground. Signals don’t travel the same way, line-of-sight communications fail, and dust can interfere with sensors. That’s why space agencies and research teams test robotic systems in Earth caves and lava tubesplaces with similar “no GPS, no sunlight, lots of rock” constraints. The goal is to build tools that can create 3D maps, identify safe routes, and set up communication nodes for future crews.

Where This Fits in the Artemis Era

NASA’s near-term focus for sustained lunar activity has emphasized the Moon’s south polar region, where permanently shadowed areas may contain water ice. Lava tubes, however, are often discussed in the context of volcanic mare regions, many of which are at different latitudes than the poles.

That doesn’t make lava tubes irrelevantit just means they may be more likely to play a role in later phases of long-duration lunar living, when infrastructure expands beyond initial polar outposts. A future scenario could look like this:

• Phase 1: Surface habitats near ice resources for water, oxygen, and fuel production.
• Phase 2: Expanded exploration of the Moon’s volcanic regions for science and construction opportunities.
• Phase 3: Permanent or semi-permanent subsurface stations in lava tubes for shielding, stability, and large interior space.

Lava tubes are less like an immediate “move-in ready apartment” and more like the Moon’s best long-term zoning opportunityonce we figure out how to build the elevators.

Common Questions People Ask About Lunar Lava Tubes

Are these caves definitely lava tubes?

Some pits may be volcanic vents or collapse features not connected to long tunnels. But the most exciting recent results involve radar and modeling that are consistent with a subsurface conduitevidence that supports the lava tube interpretation for at least some sites.

How big are we talking?

Estimates vary widely depending on location and method. Some features appear to connect to spaces tens of meters wide, and past research has suggested the potential for much larger structures. The key takeaway is that even “modest” lunar tubes could still be roomy enough for habitat modules, storage, labs, and protected working areas.

Would living underground eliminate all lunar hazards?

It reduces some major risksespecially radiation, impacts, and temperature swingsbut it introduces others, like access challenges and the need for reliable power, ventilation, and communications. A tube is a powerful advantage, not a magic spell.

Experiences: What Earth’s Lava Tubes Teach Us About Moon Living

If “humans living in lunar lava tubes” sounds wildly futuristic, it helps to remember we already have a previewright here on Earth. Lava tubes exist in the United States, and while they aren’t perfect stand-ins for the Moon, they offer a surprisingly useful emotional and practical analogy: what it’s like to step out of a harsh surface environment into a protected underground world.

In places shaped by volcanism, entering a lava tube can feel like the planet quietly flipping a switch. Outside, the landscape might be bright, windy, and exposed. Inside, everything calms down. Sound changes. Temperature steadies. You notice your own footsteps more than the weather. That “instant shelter” effect is exactly what makes lunar tubes so attractive. The Moon’s surface is famously hostile; a subsurface environment could offer astronauts a stable place to work, rest, and store equipment without constantly battling extremes.

Consider sites like Lava Beds National Monument in Northern California, where volcanic processes have created a dense concentration of caves. Even without turning this into a travel brochure, the concept is easy to grasp: volcanic terrain can create networks of natural underground spaces, some small and some sprawling. On the Moon, similar networks could existonly older, drier, and potentially larger in scale because of the Moon’s different gravity and erosion history.

Scientists and engineers don’t just admire lava tubes because they’re cool. They test technology in them. NASA has experimented with robotic systems in Earth lava tubes to practice the kind of underground exploration that could one day be used on other worldsthink of it as rehearsal in a natural “space-like” environment where GPS is useless and the lighting is whatever your equipment provides. These tests aren’t about adventure for adventure’s sake; they’re about learning how robots might map a cave, detect hazards, and relay datatasks that would be essential before sending humans into a lunar pit entrance.

There’s also a human-factor lesson that caves teach fast: living underground changes your sense of time. Without a sun overhead, your brain has fewer cues. On a lunar base, that means lighting and schedule design aren’t fluffthey’re health and performance tools. The experience of working in enclosed, dark environments on Earth has shaped how mission planners think about crew routines, mental well-being, and the importance of controlled “day-night” cycles even when the environment doesn’t provide them.

And then there’s the strangely hopeful part. Lava tubes remind us that “habitable” doesn’t always mean “comfortable by default.” Humans make places livable through engineering, organization, and habit. A lunar tube would start as rock and darkness, but it could become a protected zone for science labs, storage depots, power-routing infrastructure, andeventuallyliving quarters that are safer than any surface tent could ever be. It’s not that caves are cozy. It’s that caves are workable. On the Moon, workable is a big deal.

So when scientists talk about lunar lava tubes as future habitats, they’re not pitching a fantasy. They’re pointing to a real pattern: nature sometimes builds the shelter firstand then it’s up to us to build the life inside it.

Conclusion: The Moon’s Best Real Estate Might Be Underground

The discovery story here isn’t “scientists found a ready-made Moon apartment.” It’s something more useful: researchers are steadily converting a long-held theory into evidence-backed targetsspecific pits and subsurface structures that could be explored, mapped, and eventually used.

If lunar lava tubes can be confirmed, accessed, and engineered for safety, they could change how we think about living off-Earth. Instead of hauling massive shielding to the surface, we could leverage natural geology. Instead of fighting brutal temperature swings, we could operate in a steadier environment. And instead of imagining moon bases as fragile domes on open plains, we might build them like the smartest desert towns on Earth: partially underground, protected, efficient, and designed around survival first.

The Moon’s surface will always be part of exploration. But the Moon’s long-term futurethe one that includes sustained research stations, expanded operations, and maybe even something like a permanent settlementmay depend on what’s beneath our boots.