In “NASA Takes on the Galaxy” – one of the presentations that I have been doing on my tour with Wizard World ComicCons I cover the Moon, of course, and how NASA is doing the heavy lifting – the O2 [using Lunar Flashlight – a 2017 mission to spot the watery/icy deposits from its 12 mile above the lunar regolith orbit, then Resource Prospector-a rover that will take that map and fill in the details using its various spectrometers one for ground level and one for up to 3.3 feet deep.], the radiation [from a way cool Radiation detector that is far enhanced over anything previous to a radiation shield for working on the moon that repels radiation instead of just blocking it, to a bio-capsule that treats astronauts for radiation even if they have no idea…]food [3-D food printers to hydroponically grown food and more.] and of course habitations.
Given that here on Earth we have to contend with 25 million meteors a day, most of which are burned up in our atmosphere, the others land in the huge bodies of water the Earth hosts, few in populated areas, the Moon which lacks our protection must be dangerous. What with radiation and other concerns as well. Yes, the goal is to operate above ground in the day, but wouldn’t you rather close both eyes when sleeping – i.e. not have to worry so much about incoming or the radiation? Lunar regolith from about 9-14 inches thick protects you from radiation so living underground would be safer and not reliant on the various technologies that might hiccup while you sleep. There is a plan to take the underground caverns and robotically have the cleaned up and prepared for when humans arrive, but now that the moon already has these caverns as well, living and working on the Moon just became that much more cool!
-CARICATURE of LAVA TUBES & City of Philadelphia within (THEY ARE THAT BIG!!!)
So – the Earth’s moon is filled with tons of tunnels that were formed thanks to volcanic eruptions and flowing lava. Future colonists can breathe a sigh of relief that not only will they be ‘housed’ safe from all the radiation & meteors but they will have plenty of elbow room. [Have you seen those small white domes used for habitation? Like a tent for backpacking only it’s not optional!]
According to NASA’s GRAIL mission (Gravity And Interior Laboratory) suggests that these lava tubes may have a diameter in excess of 1 kilometer. That means we could fit a dormer for the human component and then next door an area of a football field for growing plants hydroponically.
The plan for Mars and it’s huge caverns is to enlist the help of robots long before a human gets there to clear out the cavern. One of the great features are these columns (Columnar Basalt) of hardened lava. One of the duties of the robots would be to eliminate the columns that are not study but keep behind those that are strong and so provide safety to the cavern. But that is on Mars. On the Moon, there is Basalt as well or at least it is theorized to exist.
Evidence such as the sinuous rilles observed on the surface suggest that not only do lunar lava tubes exist, but they are possibly rather large.
The presence of sublunarean voids has been confirmed via the “skylights” seen in the below Picture.
-SOUTHEAST VIEW ACROSS VALLIS SCHROTERI
If you are wondering if empty tube more than 1 kilometer wide could be structurally sound on the Moon, a Perdue team led by David Blair – a graduate student in the Department of Earth, Atmospheric and Planetary Sciences have found that if the lava tubes exist with a strong arched shape such as those on Earth, they would remain stable at sizes as large as 5,000 meters (several miles) o the Moon.
The stability all depends on factors such as width, thickness of the roof and the stressed state of the cooled lava. The team modeled a wide range of these variables.
An additional comment; Lunar Regolith – when heated in the microwave becomes a solid. Not that we’ll bring microwaves but…