Phil Plait of Bad Astronomy posted a few days ago about caved-in lava tubes on the Moon. This isn’t really new news, but it’s still pretty darned cool news. He posted some images of the cave. However, I found a major, glaring error in the LROC image data.
I fixed it.
Seriously, though…those sites are perfect premade Moon base locations. Imagine a team of astronauts putting an inflatable dome over the hole in the roof, belaying down there, putting inflatable endcaps a few tens of meters down the lava tube in each direction, spraying expandable foam sealant into all the crevasses, and using some ISRU atmosphere generators to pump the tube full of oxygen.
Love the concept, although it doesn’t look like NASA is thinking that way at the moment. One question though, in light of Apollo 1, I’d think we wouldn’t want a oxygen-rich atmosphere, right? Would we have to carry nitrogen there for the purpose of safeing the atmosphere against fire?
The Apollo 1 fire was not the result of solely a 100% oxygen cabin atmosphere – 100% oxygen is still fairly common in fighter cockpits, diving, and space suit EVAs. The disaster was also the result of extra-high pressure, solid mats of Velcro all over the CM cabin, and frayed wiring. It took a perfect storm of all these ingredients to cause that fire. That said, getting rid of as many of those elements as we can will mitigate the risks.
So, if possible, yes. I’m not sure what the relative oxygen and nitrogen content of the materials accessible from inside the lava tube might be (at least if there’s water ice, we could extract the oxygen). Nitrogen is only one option for padding out the mixture, too. Just about any inert gas would work – all we require is the O2!