Posted on 04/05/2015 5:33:02 PM PDT by BenLurkin
"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," said David Blair, a graduate student in Purdue's Department of Earth, Atmospheric, and Planetary sciences. "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."
The researchers applied known information about lunar rock and the moon's environment as well as civil engineering techniques to make their findings. They found the stability of these lava tubes depended on width, roof thickness, and the stress state of the cold lava. The results suggested these types of tunnels could be stable if they matched the determined criteria.
(Excerpt) Read more at hngn.com ...
Heh. Continuously. I believe your question pertains more to strikes large enough to cave in one of these lava tubes, in that case, not as often, but there’s not much of a system in place to monitor such impacts.
http://www.freerepublic.com/focus/news/809572/posts
http://www.freerepublic.com/focus/news/848926/posts
http://www.freerepublic.com/focus/chat/1216757/posts
http://www.freerepublic.com/focus/news/1313256/posts
http://www.freerepublic.com/focus/news/1546568/posts
Indeed he did...
About the same as earth gets hit ... :-) ...
Let’s send Bill de Blasio up to be the first mayor of the moon.
Not very comforting, as our outer atmosphere gets hit quite a lot. Maybe we suck some away from the moon, but still. Are we talking about building air-tight bladders in these lava tubes? Quite apart from the initial blast, seismic implications would be huge.
I wouldn’t be building cities in them if they tend to collapse, though.
"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. Dwelling space for several hundred thousands of our people could easily be provided. A computer could be set and programmed to accept factors from youth, health, sexual fertility, intelligence, and a cross section of necessary skills."
“I must confess, you have an astonishingly good idea there, Doctor.”
All caves will collapse eventually. It might be next year or it might be in a million years. Smaller lava tubes would likely be more stable.
Personally I suspect the first long term habitation on the moon will be hunched down beneath the rim of a polar crater. Its cold in the darkness but offers some protection from solar flares and solar panels mounted above the rim can be in constant sunlight.
The Moon is a Harsh Mistress.
Spoil sport! Bringing facts to a thread is as bad as reading before posting.
My own contribution is, “the deeper, the better.” I would want as much roof over my head as possible for protection from impacts.
Scientists have found hundreds of pits on the lunar surface that could provide shelter to astronauts exploring the moon.
Some of the pits, which are primarily located inside larger craters on the moon, are nearly 3,000 feet (900 meters) wide, researchers said. NASA showcased the lunar pits in a new video about moon caves and future exploration.
“Not to mention the homeowners association is strict.”
That’s right. No operating your Interrossiter device after 11PM.
There are identical pits on mars.
Wouldn’t be so bad, except for that whole “no breathable atmosphere” think. Details...
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