Giant Lava Tubes Possible On the Moon 124
schwit1 writes: New analysis of lunar geology combined with gravity data from GRAIL suggests the Moon could harbor lava tubes several miles wide. "David Blair, a graduate student in Purdue's Department of Earth, Atmospheric and Planetary Sciences, led the study that examined whether empty lava tubes more than 1 kilometer wide could remain structurally stable on the moon. 'We found that if lunar lava tubes existed with a strong arched shape like those on Earth, they would be stable at sizes up to 5,000 meters, or several miles wide, on the moon,' Blair said. 'This wouldn't be possible on Earth, but gravity is much lower on the moon and lunar rock doesn't have to withstand the same weathering and erosion. In theory, huge lava tubes – big enough to easily house a city – could be structurally sound on the moon.'" You can read their paper here (PDF). If this is so, then the possibility of huge colonies on the Moon increases significantly, as it will be much easier to build these colonies inside such lava tubes.
Oblig (Score:5, Funny)
I. for one, welcome our... no, wait... imagine a beowolf cluster of... um... in Soviet lava tubes, er, the tubes... the intertubes... no, no... these tubes are like a car, see, in that they... they... ok, then, Netcraft confirms that these tubes... well, but BSD is definitely... Aw, futz. I'm memeless, you insensitive clods!
Sounds like a good DF embark... (Score:1)
Personally, I'd like to embark on one of these magma tubes in Dwarf Fortress. It can't be that much harder to ensure fun on than a haunted glacier, though I will have to remember to bring extra Oxygen at embark....
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How about, "Hey, check out the lava tubes on the moon."
"Hey, that's no moon!"
"Heh heh, and that ain't a 'lava tube' either!"
Not a new idea (Score:2)
Re:Not a new idea (Score:5, Informative)
"The Moon Is a Harsh Mistress." Robert Heinlein, 1966.
Re:Not a new idea (Score:4, Informative)
Same author -- The Menace from Earth (1957).
Not sure if it were "lava tubes" (it's probably been over 30 years since I read that), but the idea of giant caverns being possible due to low gravity + high atm pressure was sure there.
Re:Not a new idea (Score:4, Informative)
Wow. This internets thing is cool.
From Menace:
"Most of the stuff written about Bats' Cave gives a wrong impression. It's the air storage tank for the city, just like all the colonies have - the place where the scavenger pumps, deep down, deliver the air until it's needed. We just happen to be lucky enough to have one big enough to fly in. But it never was built, or anything like that; it's just a big volcanic bubble, two miles across, and if it had broken through, way back when, it would have been a crater."
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So ... Heinlein was writing within the accepted science of his day (no surprise there), which was that the craters of the Moon (there were no others known) were primarily a volcanic phenomenon.
In the 1960s there was a protracted dispute between various people in the geology community on determining the origin of the lunar craters. Eventually it was won by the people proposing that th
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"So ... Heinlein was writing within the accepted science of his day (no surprise there), which was that the craters of the Moon (there were no others known) were primarily a volcanic phenomenon. "
I'm missing what you are trying to say -- is it that there were no volcanoes on the moon? Ever? If so, I believe you are wrong. Check out volcanic glass recovered by Apollo 17 and more recent papers on fairly RECENT volcanic flows (as early as 100 million years ago).
Besides, by the 1950's, I believe it was gener
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Then you failed to indicate how his "science is wrong". A volcanic cavern or tube formed a few billion years ago or 20k years ago wouldn't real
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Quite. It's a damned shame the way Buzz Aldrin and his crew died screaming on live TV, and on what was to be such a historic Moon-landing mission too.
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They're not claiming it's a new idea, they're saying that such tubes are structurally sound for the purpose.
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Sure, and sci fi has had anti-gravity for many decades, but I'm pretty sure that information suggesting it was actually possible would still be news.
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I don't recall tubes, but it's been a while. I do recall at least one dome (which I took to be a bubble in the rock), big enough to house offices and maybe a public space of "town square" size.
And ice pockets big enough to mine. That one, I figured was just invented to make the story work and/or wishful thinking.
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"lava tubes" (Score:5, Funny)
What he really means are giant lunar worms (ala Herbert). Just you wait, the first lunar colony will be smashed to bits by lunar death worms defending their ancestral homes from pesky, tiny intruders.
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can't wait for the lunar spice
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I think what he really means is that Luna already has the internet. The tubes are there.
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What he really means are giant lunar worms (ala Herbert)....
Lunar Worms? Don't forget about the Lunar ticks.....
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My first thought was the moon worms from Major Matt Mason [wikipedia.org] stories/toys of the late 60s/early 70s.
Ah, ok:
There was also a Big Little Book, Moon Mission written by George S Elrick and illustrated by Dan Spiegle published in 1968 that had the astronaut and his friends confront both giant rabbits and huge burrowing worms on the moon.
I had the book and a couple of the astronaut toys. I didn't remember the rabbits until reading this...
The Cave is Collapsing! (Score:2)
"This is no cave."
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Why blow up the moon when there's so much stuff to blow up here on Earth?
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Blowing up the moon would be a highly efficient way to blow up stuff on earth. Assuming only random distribution of the resulting fragments.
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That would have to be one hell of an explosion - not only would it have to shatter the moon, it would have to impart enough energy to the pieces to completely escape its gravitational well - less than that and the pieces would either re-coalesce or form a ring system in the Moon's orbit, depending on just how much less.
Even a truly massive explosion wouldn't be nearly as damaging to Earth as you might imagine - the Earth, as viewed from the moon, subtends only 1.2 milli-steradians, out of the total 4pi, so
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So, like I said. Blow up the moon, and it'll blow up a lot of stuff on earth.
I didn't say it would blow up the earth.
I didn't specify how big an explosion, other than "blow up the moon", quoting the GP, which is going to be in the darned large side just to begin with.
As for your gravity fall back idea, when the moon is fragmented, the chunks near the surface are furthest from the others, which are all further from each other, so total gravitational pull is much less, plus, any leading elements are probably
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Of course pieces of moon raining down on Earth would be devastating, my point is that it would be far *more* devastating if you simply unleashed the same amount of energy directly on the Earth instead.
As for the specific energy required to break up the moon - it would actually be even higher than that required to get a single rock off the surface. Everything on the surface has a certain gravitational potential energy which must be overcome to escape the gravity well, as you go deeper that energy requiremen
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Applying the same explosive force required to blow up the Moon to blowing up a portion of the Earth instead would only be "more devastating" if you are purely measuring devastation potential in terms of forces of impact or explosive forces.
Don't forget that by and large, the opinion of the Moon in its relationship with life on Earth is more or less "vital". We have no idea what would happen to our weather and atmosphere, our oceans and water tables, or our life cycles if the Moon were obliterated.
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You are grossly underestimating the energies involved. Oh goody, Google located someone else who's already done the math (https://answers.yahoo.com/question/index?qid=20090102113458AADvZ2j)
Their conclusion was that to destroy the moon (i.e. completely neutralize the gravitational potential energy lost to the accretion of mass) would require 1.2445 x 10^(29) Joules, or the equivalent of 592.6 billion Tsar Bomba fusion bombs (the largest nuclear bomb ever detonated, at ~54 megatons of TNT, with a total destr
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Well then. Unless your figures are wrong (who knows?) then I guess I stand corrected.
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Moon Internet (Score:5, Funny)
We could make a civilization within the series of tubes!
Mr. President! (Score:2)
Caves (Score:5, Informative)
Don't we already know that these exist [io9.com]?
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Theoretically possible (Score:2)
TFA concludes that really large domes might be possible.
Not that are any.
Not that they could be sealed and made habitable.
Just that in the Moon's gravity they *theoretically* might not collapse.
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Not that they could be sealed and made habitable.
Sealing them is pretty straightforward actually, you just use a sprayable plastic to coat to the interior. Combine that with a series of air pressure sensors throughout and a small maintenance crew and you're all set. Settling the moon isn't really a problem from an engineering perspective, the issue is economics. It's expensive to get there, it's expensive to live there and so far there isn't much we want there. The only real things that would make any sense at the moment are A) A military installation
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I cannot conceive of the amount of energy a mass driver would take. The moon is orbiting at 3,683 km/h, so you would have to slow a projectile by that much to hit the earth, and it would have to be very precisely aimed to hit a spot on the surface of the earth as it would take days to hit the Earth. The moon is a terrible place to put a kinetic weapon, but LEO isn't any better as you need to slow the projectile by 28,080 km/h to be able to hit the Earth, and be able to aim yet again.
This isn't just a matt
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Hmmm, you sound like someone who has actually spent a lot of time installing materials over your head, supported on ropes of uncertain anchorage, or installing the scaffolding truss work to avoid having to trust the rock which you're trying to stabilize. Or rather, you sound like someone who hasn't done exactly that.
I'm not saying that it's not do-able. But that doesn't mean to say it's "straightforwar
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I'm not saying that it's not do-able. But that doesn't mean to say it's "straightforward".
I was suggesting that it didn't require any new scientific discoveries and that our current technology could be adapted to the task. It's an engineering and construction problem certainly but not out of reach.
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Moonbase-1 will be built on blood (boiled to a powder) and bones.
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Moonbase-1 will be built on blood (boiled to a powder) and bones.
And that makes it different how? Construction has always been dangerous business.
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We actually had to give up an hour of our off-shift time last Sunday, after the safety meeting, to go through some corporate "culture building exercise" (something I normally associate with home brewing) about how in the past the death rate was reckoned at about one corpse per million dollars spent, but by the investment of 0.13 million dollars (a leg or so), the guy who constructed the Golden Gate Bridge save
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Tubes, not domes - somewhat different mechanism, and radically different shape and size. On Earth the theoretical limit of lava tube length is apparently 30-900km, depending on assumptions - that's one hell of a lot more enclosed area than the width would suggest. And on the moon we have discovered cave-ins 900m across, so that suggests that tubes at least roughly on that scale do exist.
And if tubes that large can theoretically exist, it seems reasonable to assume that much smaller stable tubes, say only a
Say Cheese (Score:5, Funny)
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moonquakes (Score:2)
I didnt see ay mention of moonquakes. Considering these are a real and verified occurrence and considering the considerable amount of energy they release as has been recorded, any prediction of the structural integrity of lava tubes in the moon that doesnt take moonquakes into account is likely to be wrong.
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You have it exactly backwards. We don't know that they're there at all. All the study claims is that it's possible for them to exist because gravity alone wouldn't collapse them. GP is right, there are other things that might collapse them. You're also sort of right. IF they exist after all this time, it's pretty darn certain they're structurally sound.
Do they exist, though? We don't know.
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Um, yes we do know that they're there. There are plenty of pictures of skylight caveins and entirely collapsed tubes from satellites orbiting the moon. On Mars, too.
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We have pictures of 5000m wide lava tubes on the moon? Link, please? I never heard of that. Pretty cool if it's true.
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All of the fools in this thread mentioning "meteorite bombardment" have not the foggiest. Moonquakes are a lot more powerful and a lot deeper than the faint tremors that would be caused by surface impacts.
But that's no surprise that people aren't interested in moonquakes or never heard of them before, even if they're lunar scientists. Even NASA didn't want to acknowledge their existence at first.
But look at them, now: http://science.nasa.gov/scienc... [nasa.gov]
The truth is that nobody is sure what causes the most pow
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reinforcing living structures would be necessary. but my thought is that the tech we have for building in seismic regions should transfer to moon just as well. Granted we would need more long term data.
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I didnt see ay mention of moonquakes.
Did you read the paper? They didn't model any seismic activity, nor did they model any confining stresses. As such, their:
failure values are slightly conservative (i.e. low in magnitude) in order to compensate for [their] not modeling other stress sources such as seismic shaking from meteorite bombardment.
The point of the exercise was to theoretically confirm that large lava tubes can exist because:
Recent in-depth analysis of lunar gravity data from the Gravity Recovery And Interior Laboratory (GRAIL) spacecraft has suggested the possibility of lava tubes on the Moon with diameters in excess of 1 km.
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Have you actually looked at the magnitudes of moonquakes? Apart from the sporadic ones caused by impacts, they're not powerful quakes, and they're deep below the surface, which add up to low levels of ground shaking. Which is what you are really concerned with.
The typical shaking caused by a 5.5 magnitude earthquake (on the moment-magnitude scale, since the Richter scale
Diamonds? (Score:2)
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Yeah, a crash. Diamonds aren't really all that rare and can be manufactured. There might be some fashion value in "gemstones from space", if it can be proven that they are lunar in origin by some kind of analysis.
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Kimberlites pipes are not hollow; they are filled with rocks and they are usually vertical and very deep (and partially exposed by plate tectonics which does not exist on the moon). This discovery is of horizontal hollow pipes full of nothing, not even air.
Re:Diamonds? (Score:4, Informative)
Very few volcanic pipes are diamond laden on Earth - primarily just kimberlites, which require a special type of volcano feed by very deep magma that's high in volatiles. They're almost all very old. The moon tends to be poor in volatiles and the depth requirements would be far greater to achieve the necessary pressures, at least 1/2 to 2/3rds of the way to the core.
Still, who bloody knows?
There's all sorts of gem possibilities on the moon, way too many to list here. They're probably the most valuable export-to-earth lunar resource we could mine at this point in time, as you can imagine what sort of premium the market would put on them even if they're pretty much the same as earth gems (let alone if they're mineral species not found on earth)
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When I was a student of mantle petrology (as opposed to earning a living grubbing around in the crustal ephemera), we couldn't say "there is no chance of a kimberlite being emplaced somewhere on Earth tomorrow. And I still don't see any particular reason to make such an assertion. And to be
David Weber (Score:2)
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'Dahak' trilogy. An OK read, but a bit frustrating since the story-line was abandoned - huge unresolved plot points.
The Moon is like a series of Tubes (Score:2)
The Moon is like a series of Tubes - If Ted Stevens had been an astronaut.
Could, if, in theory (Score:2)
These appear too many times in the article to take the idea seriously.
So are giant mouse people living in the cheese (Score:2)
Tell me what we've found not what we might find.
Hadley Rille? (Score:2)
I thought it was a collapsed lava tube. The lunar surface is pretty heavily pounded so hollow tubes are fairly unlikely, at least accessible ones.
Coincidence (Score:2)
Low gravity (Re:Stupid.) (Score:3, Interesting)
One use would be for retirement communities — the thought occurred to me some 10 or 15 years ago, but then read about it somewhere in Heinlein's writings.
The low gravity of Moon would allow the elderly (and other infirm) to remain mobile for many years after they would've become wheelchair-bound on Earth... Considering the wealth of (relatively) many of the elderly in the Western wo
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And would mean that earth-quality emergency medical care would be almost impossible to get.
Seriously, the last people you want to put onto a rocket and launch at several Gs up, into a high radiation environment, and then land on a desolate rock far from the rest of human society, is people who can die from hitting something too hard.
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Blah! Of course, well-qualified medical personnel would have to live on the moon with their (would-be) patients.
The acceleration should be possible to overcome with well-designed equipment. Sure, some of the people may not be fit enough to reliable survive the travel, but enough of them will be able t
Re: Low gravity (Re:Stupid.) (Score:1)
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Actually, if you're going to stick someone into a high radiation environment, the older they are the better. It wouldn't be difficult to send good medical equipment and personnel along as well.
The people you sent would have to go while they were healthy enough to make the trip, but once they were there, they might enjoy a longer life than otherwise: low gravity lessens the risk of falls, but also eases the strain on the heart and circulatory system.
And the stream of centenarians dying would provide fertili
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And the stream of centenarians dying would provide fertilizer for making lunar soil.
That's both amusing and practical, I like it.
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The low gravity of Moon would allow the elderly (and other infirm) to remain mobile for many years after they would've become wheelchair-bound on Earth... Considering the wealth of (relatively) many of the elderly in the Western world, they may be able to pay for such retirement even before some other industries take hold up there.
Or we can stick them in a bed with VR goggles on.
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Wouldn't the elderly be better off on a space station? You could actually control the level of (artificial) gravity by designing it with rings and spinning the station (ref. almost every scifi story in space). They could start off at the outer layers (maybe 0.5 G equiv.?) and work their way up through the rings as their capabilities decreased. When they perish (dead ringers?) they could be released to fall back to Earth (shooting star), or on an orbit to intersect the Sun (if they need more flare) or whe
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I would think, constructing such a station would be orders of (decimal) magnitude more expensive and complicated, than building a habitat on the Moon.
Yes, your deliveries from Earth would be cheaper for such a station, but you are going to need a lot more delivered starting from scratch in empty space. And maintaining a constant spin is a non-trivial engineering task, whereas we already know just about everything required for building on the Moon.
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You would be wrong.
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The low gravity of Moon would allow the elderly (and other infirm) to remain mobile for many years after they would've become wheelchair-bound on Earth.
In order to enjoy 0.3 g on the Moon, you need to suffer 3+g for a good ten minutes leaving Earth. I'm not sure that the elderly or infirm will stand for that.
The Saturn V's actually were one of the slowest-accelerating human-rated craft to ever launch, and they hit a peak of 40 m/s^2, about 4 g, at MECO 1:
http://history.nasa.gov/ap11fj... [nasa.gov]
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Fascinating link. I wonder how the Mercury and Gemini G curves look.
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Good question. According to this guy, both Mercury (no mention if Redstone or Atlas) and Gemini broke 7 g:
http://space.stackexchange.com... [stackexchange.com]
I would imagine that the Gemini curves looked something like g = t + sin(t) as they had real pogo problems with the Titan rockets. If you find an actual graph, please post it!
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There's unlikely to be much in terms of heavy metal deposits, apart from asteroid finds, which doesn't sound like a market big enough to justify the expensive of the trip. Helium 3 is a total red herring. And of course your labor and hardware costs will be through the roof due to the incredible expense of shipping consumables. Isotopic Enrichment of light elements in-situ seems quite unlikely as a consequence.
Still, I can envision a market. Just any old moon rock will always have an interest from collectors
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Granted, Helium-3 would be a challenge to mine, and we don't actually have any use for the stuff yet - that would be a more long-term resource. But Lunar soil is roughly 40% oxygen, which would be an extremely valuable resource on its own (for breath-gas and LOX-using rockets). And assuming a ready source of hydrogen and/or carbon can be found there's great potential to synthesize water and rocket fuel there as well. If nothing else it would potentially be a hell of a lot cheaper shipping just hydrogen fr
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There is no point in building large cities on the moon. Seriously, why? If you want to live underground, do it on Earth.
I want to be the founder of Moriah.
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For starters, on Earth you have to deal with Earth governments, worry about Earth wars, and guard against Earth diseases. On the moon there would be potential for a fresh start - much the same motivation as moved most early Europeans to colonize the Americas. Granted it would take a far more rugged and visionary colonist to settle a dead rock than a lush continent, but so what? Perhaps the self-selection of visionaries and dreamers crazy enough to colonize the Moon would lend itself to forming a new kind
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There is no point in building large cities on the moon. Seriously, why? If you want to live underground, do it on Earth.
I see the Moon as the gateway to the rest of the Solar System. It's a ready source of raw materials outside of Earth's gravity well but has enough gravity to keep things from floating around much which makes living there easier than in zero-G. Lack of atmosphere and low gravity make launching anything to orbit or beyond pretty easy. Setting up an interconnected series of solar power collectors around the equator would take care of power needs. The Moon may even have enough gravity to ameliorate the wors
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lunar gravity is your friend, also support structures.
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I have hiked in that very tube (about a mile long). If you had to live in a lava tube, it would be both easy to reinforce with something like shotcrete, being close to and parallel with the surface, and easy to create new entrances. It would be ideal protection from radiation.
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You wouldn't use Earthly gunite on the Moon, but something more like epoxied regolith over carbon fiber mesh. The principle is the same. The article cites the possibility of large lava tubes. If those exist, there will be smaller tubes that will be early candidates for reinforcement.
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That's what GRAIL is, and yes, it's found signs of large lava tubes. So says the summary.