The Infrastructural Needs of a Lunar Base

As we move further into this new decade, our sights on human exploration are starting to expand. The idea of walking once again on the moon is becoming more of a reality than a far-off dream, with numerous countries and companies setting their sights on lunar exploration and beginning the steps of creating a cislunar economy.

A fundamental first step for this is figuring out how exactly astronauts will permanently live on the moon, meaning we need some sort of moon base. We have plans and bright ideas for a lunar space station, but not any concrete methods for designing lunar habitats and setting the foundations for a future lunar city. The question is, how would we do this? What exactly goes into constructing a self-sustaining lunar base, and what would it look like to us? Where are we now in this process? Let’s find out!

When it comes to planning out the construction of a lunar base, the exact location of it is what we should think of first. Where on the moon would be most beneficial to us in an economical, scientific, and viable lens? Let’s explore every option and look at what they have to offer, beginning with the lunar north and south poles. The poles have been considered one of the most promising areas for lunar exploration because of their access to necessary resources and geological features. Specifically, the Malapert crater located toward the lunar south pole has come up numerous times when looking for a landing site.

Malapert is a 69-kilometer wide indent into the moon’s surface that also consists of a 5-kilometer high ridge on its southwestern edge rim, colloquially known as the Malapert Mountain. Malapert Mountain is basked in sunlight for 90 percent of the moon’s orbital period, vital for a lunar settlement. A reliable, easy power source is solar energy that could not only continually power a settlement throughout the day but can be stored in hydrogen fuel cells for use during the darker periods of the moon’s orbit.

In this area of lunar terrain should exist permanently shadowed craters that contain pockets of frozen water ice that have most likely never seen the light of day. Water is the gateway compound to creating vital resources needed in a lunar base, such as breathable air within a lunar habitat and rocket fuel. Rocket fuel is especially important since launching a rocket to orbit on the moon requires much less power than on Earth due to the combination of low surface gravity and an extremely thin atmosphere. Rocket transport comes into serious play when discussing how a lunar base can economically sustain itself later.

The downward slope of Malapert that is not facing the Earth could be a perfect spot for installing an observatory containing a radio telescope on the moon. We want to try to avoid any interference that could be sourced from Earth’s own radio wave spectrum. In the more dark areas that receive less sunlight, an infrared telescope that needs to work in cooler conditions could be built. Along with being a great spot to map out locations for geological exploration and a decent site for a centralized communications depot, Malapert mountain showcases how the poles are the true lunar base hotspot.

We can quickly look at another option, which is along the moon’s equatorial plane. High amounts of helium-3 are likely to be present in this region, which would serve as an essential commodity for a future sustaining lunar economy because of its depletion here on Earth. It would be an easy place to land on and launch from, but then we run into various problems, including a viable power source that can power the settlement through the 14-day lunar night and an unreliable water source. We could potentially use fuel cells to store enough power to get us through those long nights, but conserving power could possibly become an issue during those times when we need the stored energy. There is also the possibility of using either a nuclear fission or fusion reactor to power the base, the latter having a lot of fuel at its disposal due to the copious amounts of helium-3. Sticking to the polar region seems like our best bet for now, though.

Now that we have a location for our moon base, what about the actual base itself? We have two routes for constructing a habitat for astronauts to live in, including constructing a surface habitat or an underground habitat.

When it comes to a surface base, this is most likely what we’ll see towards the beginning of the creation of the first lunar base. When building a settlement on the surface, the key factors to consider are how to protect from both the hazardous amounts of radiation, temperature control, and micrometeorites. The lack of a thick atmosphere on the moon results in the surface of the moon having similar conditions to the vacuum of space, leading to fluctuations in temperature extremes, which can range from 123 °C to -153 °C depending on whether it’s day or night, and dangerous amounts of radiation. In late 2020, China’s Chang’e 4 moon lander on the far side of the moon was able to make radiation measurements for the first time. It found that astronauts would receive 2 to 3 times more radiation on the moon than an astronaut does currently on the International Space Station, or nearly 200 to 1,000 times more radiation a person experiences on Earth. It is crucial to protect against this in a moon habitat so that astronauts do not have extreme risks of cancer and other health hazards developing.

To protect against this, along with solving the other issues of micrometeorites and temperature control, many have suggested using the soil from lunar regolith as a solution, which has been found to provide a substantial amount of protection against cosmic radiation. This is where in-situ resource utilization will become key. There are many ways to accomplish this. One study discussed the manufacturing of glass and mirrors from lunar regolith simulant, taking in the regolith and heating it using microwave radiation. The glass was found to be malleable and the mirrors, if smooth and porous, could reflect up to 85% of incident solar light. Another idea brought up by a private architectural firm was integrating inflatable habitats and the lunar regolith. The habitat could be sent over to the moon pressurized, and a lunar regolith shell that would serve as protection would be built around the inflatable bit. These are great examples of how we can utilize lunar materials to create a safe environment for astronauts to live in.

We have to start thinking a little bit harder when it comes to the construction of an underground base, and I see this as something that will be explored later on. Locating and excavating lunar lava tubes, channels formed within the moon due to basaltic lava flows, will be the place to start with this. These cavities are great options because we don’t now have to face the issue of cosmic and solar radiation, micrometeorites, and temperature control, since being underground will provide both protection and insulation, and they have good structural integrity. The actual work arises when trying to excavate the tubes while keeping that structural integrity. Some have suggested creating concrete-like material to keep the surface from collapsing on itself due to gravity or even utilizing the lunar regolith to create a more robust structure. This is a future problem to worry about, as sending over an inflatable habitat to the moon is much more viable than figuring out how to excavate a lunar lava tube.

As we create habitats for humans to live in safely, the next step is to make the moon sustainable through exporting materials, mainly helium-3, to places such as Earth or even a future space station placed at a Lagrangian point. As mentioned above, creating rocket fuel on the moon and launch from here will be highly beneficial and cheap. We can even think about using mass drivers, basically electromagnetic catapults, to launch objects into space without creating a rocket. This can all eventually lead to the first space elevator being built on the moon, becoming the ultimate cargo transfer station and boosting the moon’s future economy.

Alright, we now understand what the infrastructural needs of a lunar base are. What are we doing now to get there?

NASA’s Artemis program, which aims to return to the moon, specifically its south pole, by late 2024, has been slowly progressing. In October 2020, NASA and seven other space agencies from around the world signed the Artemis Accords, a partnership that will aim to create principles of cooperation that will lead to a sustainable lunar presence. Their flagship Space Launch System (SLS) rocket is slated to launch later this year after numerous delays. The goal after 2024 is to have a permanent moon presence, doing this through both constructing the Gateway lunar space station, and then by launching the Lunar Surface Asset Deployment in 2028, the first true lunar outpost that will have existed.

Despite this, some countries have other plans for lunar exploration. On March 21st, 2021, China and Russia signed a memorandum of understanding that leads to their cooperation in building the International Lunar Research Station (ILRS). This project will span from the mid-2030s to the mid-2040s, with the construction of a base near the moon’s south pole.

So far, this is every bit of information we have on a future lunar base ever becoming a reality. Slowly and steadily, humans will make their way to the moon, make those steps for all humankind once again, and hopefully stay there, paving the way for the first humans on Mars. The question now is whether we can successfully expand our presence to the moon or continue to dream of human settlement outside of Earth’s gravity well. Let’s see!