Caves of the Moon

jeno passes along this excerpt from New Scientist: "A deep hole on the moon that could open into a vast underground tunnel has been found for the first time. The discovery strengthens evidence for subsurface, lava-carved channels that could shield future human colonists from space radiation and other hazards. ... The hole measures 65 meters across, and based on images taken at a variety of sun angles, the hole is thought to extend down at least 80 meters. It sits in the middle of a rille, suggesting the hole leads into a lava tube as wide as 370 meters across."

Comments

So then, now we know

[countertrolling]

The moon is made out of Swiss cheese...

Access point to the hyperlogos

[drinkypoo]

Sorry I can't find a better link, but you don't really need a lava tube for settlement, it just makes it cheaper and easier. You're still going to need an inflatable habitat or similar (honestly, what else makes sense?) to sit in the tube.

Re:Access point to the hyperlogos

[mpe]

Sorry I can't find a better link, but you don't really need a lava tube for settlement, it just makes it cheaper and easier. You're still going to need an inflatable habitat

The obvious problem with an inflatable habitat is that anything the size of dust is going to make at least one hole in it. Patching is likely to take up quite a bit of someone's time.

or similar (honestly, what else makes sense?) to sit in the tube.

Install two bulkheads some distance apart and pressurize the space in between to 75 kPa.

Mapping Lunar Caves

[sanman2]

Seriously though - I wonder what would be the best kind of sensors/instrumentation to map underground caves and tunnels on the Moon from orbit? Isn't there supposed to be something called "cavern sensing radar" or "ground penetrating radar" that can do this stuff? If so, then how come it hasn't been done yet? Surely we're not just going to rely on finding these choice living locations by just luckily spotting some hole in the ground?

If Man is going to return to the Moon and make a permanent base there, then it might as well be done in a cave, which is much more naturally sheltered from harmful cosmic rays and meteors, as compared to living in some inflatable habitat on the surface. Heck, that's why our cavemen ancestors liked caves to begin with - because they were uniquely sheltering environments. Shouldn't there be some kind of effort to map out the lunar underground to reveal where the best locations might be? As they say in real estate - it's location, location, location!

Re:Mapping Lunar Caves

[mpe]

Seriously though - I wonder what would be the best kind of sensors/instrumentation to map underground caves and tunnels on the Moon from orbit? Isn't there supposed to be something called "cavern sensing radar" or "ground penetrating radar" that can do this stuff?

Such radar typically used on Earth tends to be in contact with the ground. So you'd need to land a vehicle. Also IIRC it is difficult to get a stable Lunar orbit, due to both the Earth being nearby and the Moon not being of uniform density.

Re:Mapping Lunar Caves

[sillybilly]

Even if there is no lunar underground cave system, we could always dig one if the need arises. Moon mining could be done subsurface, to save the unmanned underground vehicle / remote controlled robots from temperature fluctuations and space radiation exposure. People and plants and animals are unlikely to ever live on the moon, other than as a work outpost, because there is not enough gravity for healthy functioning for highly extended periods such as over a few decades. Unless you construct a space station, spin it to create gravity, and stick that in a huge huge huge underground lunar cavern, with the axles supported by very strong pillars. Then you get extra protection from asteroid hits and radiation, but you'd still have to manage an on-surface solar panel array that gets lunar day and night fluctuations every 27.3 Earth days. Unless you can find and concentrate up enough uranium and thorium underground to manage simply with nuclear power, and no need for solar energy. Unless you figure out how to use and control fusion, whose fuel is abundant and whose nuclear waste is much less, mostly irradiated structural radiation, whose properties are not too far from outer space irradiated structural components.

In free outer space, off the surface of the moon, you can spin a large enough cylinder to generate artificial gravity needed by most lifeforms for proper functioning (humans, plants), and the spinning structure does not need superstrong bearings for axial support, it just floats in a free space orbit. Asteroid hits and radiation would mandate periodic replacement of the outermost shield, but if you have triple or tentuple airlock/shield layers, the innermost shields should stay safe. Of course it'd still need a longrange radar to catch and vaporize very large and very fast flying asteroids Patriot rocket style, similar to the ones used in the 1st gulf war, shooting at Scud missiles mid flight and destroying them, or at least throwing them off track.

Re:Just one question...

[mbone]

This lava flow comes from the late heavy bombardment and so the lava tube is well over 3 billion years old. Yes, the roof might fall in, but (given that there is no erosion, and no ground water dissolving the rocks) if it hasn't collapsed in 3+ billion years, the odds are in your favor.

Now, that doesn't mean that these tubes are necessarily stable, and you would certainly want to be cautious on the first visit, and provide a roof to protect against cave-ins caused by human activity, but many of the lava tubes on Earth are quite stable, and similar tubes on the Moon would be great places to set up shop.