When we finally start to get a presence on the moon, one of the things we will do is build habitats and bases. Places to center our activities, to store our stuff, build things, sleep in, to create industries and operate businesses in. etc. What are the options for how to build these places on the moon and what are some of the the variety of strategies we could employ for designing our future habitats on the moon.
There are plenty of models to choose from when it comes to what to build on the moon, and especially in the early days we might experiment as we try to explore and find the places we want to build on and what we want to do there. There are always tradeoffs to make, so any particular building strategy will balance different groups needs in different ways.
We could model a moon base after the same modular style construction used with the ISS. These consist of large pre-built ridged modules that “snap” together with the help of some robot arms and a couple of astronauts. Once connected various parts of the structure can specialize to provide various purposes – sleeping area, scientific research area, command and control, power modules etc. Once inside, astronauts can move around and get things done without the need to put on a spacesuit and go for a walk.
Modular designs have a lot of things going for them. They can be sized to fit into rocket fairings, and combined relatively easily into complex arrangements. Over time more can be added, which means that they can be functional early on and improved over time with more space and capability.
The first permanent habitats on the moon will almost certainly be of this sort of modular unit, designed and built on earth.
Unlike the construction of the ISS where a robotic arm can freely rotate a 4 ton box around, the moon has gravity and the ground to contend with. Lining up and attaching modules on the moon is a very different construction challenge. It will require more situational accomodations for moving boulders, leveling, anchoring and lifting the components. Astronauts will need shovels and cranes for fine tuning the position of things. We’ll need entirely new capability for precision landing on the moon to avoid having to transport these large modules around to put more than one on the same site. Doing this construction with perhaps 2,3 or 4 astronauts is going to be a difficult and dangerous job.
One of the benefits of a super heavy lift rocket like SLS is that we could land a single unit habitat that avoids the complexity of on-site construction.
The realities of lunar construction have been explored in some of the lunar and mars analog missions. In 2008 there was a mission to study lunar inflatable habitats at the the mcmurdo station in antarctica. For this experiment a fully soft-walled tent was rolled out on a site, anchored and then inflated with a 3 person team dressed in cold weather gear to approximate a spacesuit. The habitat was remotely monitored for the duration of a year with a suite of sensors to monitor its performance.
Engineers learned several important lessons about what is required to keep a habitat working and built in remote and hostile locations. Dealing with mundane issues such as running wires to sensors, or attaching things to the walls (without nails/screws) or how some compressed insulation created cold areas of the habitat were key takeaways. This study is now a decade old and was limited in scope – they only slept in it for 1 night, on the floor. In terms of the viability of a purely inflated structure though, something like this might have value for some missions. It would be more accommodating than getting back into a lunar lander – like the cramped Apollo missions were limited to.
Alternatives to modular or soft inflatable designs will start to pop up once we have some more experience and have brought up the robots and 3D printers needed to start building things on site.
Fully permanent habitats will use in-situ resources
One of the simplest things we will want to do is to bury our habitats to provide extra protection from radiation and micro-meteorites. If this becomes a common strategy for the things we build on the moon, then most things will be hidden from view and those spectacular bright and tall moon cities will remain science fiction.
Will we start growing a single outpost location, reminiscent of the research facility on Antarctica, which has grown into a permanently inhabited small town? Maybe. There certainly is a lot of value in pooling our resources to one location.
On the other hand there is just so much to explore that there is huge value in being able to collect samples from all the different geologies and craters, to have installations at both poles and on the near and far side of the moon. With the goal of discovering and using things from all sides of the moon perhaps we would benefit from those inflatable re-deployable habitats like studied in Antarctica that can be deployed to places of interest or strategically between places of interest to become stopping points or caches for astronauts transiting longer distances.
Since we are going to be staying on the moon, the prudent course of action would be to invest in relocatable and permanent structures.
At the south pole, where there is a focus for the human mission back to the moon by 2024 there is the belief that the ice there would be a valuable resource to mine and refine. This could be a permanent industry that would benefit from permanent infrastruture of buildings , power, roads and larger investments in refineries or other industrial assets.
Ultimately there will be science demands that entice us to explore, and business demands that would prefer a productive permanent investment.
Over the years there have been plenty of lunar base concepts. Some done by NASA, others by arcitecture firms, and private companies and many more done by engineering students.
One of the most public has been proposed by Bigelow aerospace which hopes to be able to deploy their inflatable modules to the lunar surface. They have built some scale models to show off what a lunar base might look like with their technology.
Time will tell what the lunar missions will need and have the capacity to deploy for habitats in the next decade. Given the time demands of the 2024 goal, the first mission back to the moon will likely be little more than planting the flag. It’ll be awhile before we see concrete plans for a lunar base, especially if resources are instead put towards the Gateway station.