For Sale: Lunar Regolith

As promised in our recent IGC update post, this is the first in a new series of educationally focused posts. In case you missed the update marking our one year anniversary here at IGC, here’s a review: in addition to our usual review posts, and posts on reading and writing, we’re going to branch out into posts specifically intended to provide an educational look at a specific topic. These will be rotated into the Tuesday post pattern periodically. I’ve long had a passion for education – many of my colleagues tell me that I have a tendency to launch into “lecture mode” whenever I go to explain, well, anything – and so I’ve decided to use this platform to further that mission. Before we get into today’s topic, though, I want to establish a few groundrules.

1. These educational posts are meant to provide context, analysis, explanation, and perhaps some insight on a specific topic. They are not meant to be comprehensive.
2. Although anything anyone writes has some bias, I will attempt to present information as objectively as possible, and include multiple perspectives on issues where appropriate.
3. The nature of information, especially scientific information, is that it changes, as do interpretations of it. What I post today as something we “know” may be something that in twenty years we know to be completely false. That’s a good thing, but it is something of which to be aware.
4. Discussion on these posts in particular is highly, highly encouraged. I’ve found that the best learning (and teaching) takes place when a package of information is presented, and then there is an opportunity for discussion. So please, join the discussion below.
5. Come with an open mind, and embrace curiosity. I hate that the “why phase” is associated with toddlers and young children. Personally, I never grew out of it. However deep we go into a topic, I want you to be thinking at least one layer deeper.

As time goes on, I might establish these more formally, elsewhere on the blog, but for now, they are just something to keep in mind. Now, let’s get on with the educating.

I didn’t put any really complex thought into deciding what the first educational post was going to be about; I just came across an article that I found interesting, and went from there. In this case, it was an article from NASA about purchasing lunar regolith (yes, NASA.gov is my browser’s homepage). There were two, primary dimensions to this article, and they’re worth analyzing independently: in-situ resource utilization, and international space law.

Considering my involvement in space, I probably can’t pretend to be objective, but I’ve been advocating for more in-situ resource utilization in space travel since high school, and my commitment to those concepts has only increased with exposure. Leaving behind the fancy, technical terminology, in-situ resource utilization simply means using what’s around you. If you go camping, and gather your firewood from around the campsite, that’s in-situ resource utilization. With a few exceptions, space travel heretofore has been a primarily bring-your-own-firewood kind of operation, but that will need to change if we want to expand our space-faring capability.

To understand why this concept is so vital to the future of space travel, we need to talk about gravity. Despite being the weakest of the four fundamental forces of nature, gravity dictates how we operate in space, and it is also what puts the single largest bottleneck in space travel: launch. Launching rockets into space remains on the very cutting edge of human capability, despite all of the advances that we’ve made since we began working with such systems, and it mostly comes down to gravity. See, it takes a huge amount of energy to overcome the gravitational energy holding something to the Earth’s surface, but that energy comes in the form of fuel, which itself adds mass. If you need more energy to lift more mass, you need more fuel, which means you need to add more mass. In other words, in order to overcome the problem, you have to make the problem worse.

Aside from developing fuels with a better mass-useful energy ratio, the main way we’ve found to address this problem is staging. Most launch vehicles (in the business, “rockets” are the apparatuses that actually direct the controlled explosion of the propulsive material, while “launch vehicles” are the behemoths full of fuel and payloads that deliver things into space, what most people think of as rockets) are made up of multiple stages, or sections. When the first stage burns out, it is jettisoned, and the second stage fires. This allows the rocket to drastically cut its mass periodically, so each new stage, is able to get that much more velocity out of its fuel. Staging adds complexity, but it is the only way we have for now to solve the launch problem. No single-stage-to-orbit vehicle has yet been viable.

Now, imagine that you are attempting to go to Mars. Under the traditional, bring-your-own-firewood paradigm, you would have to carry enough fuel with you to get off the surface of Mars and back to Earth, on launch. That would mean that in addition to carrying the fuel you need to get off the surface of Earth and get to Mars (which already would mean using the largest launch vehicles we have), you would also need to lift enough fuel to then reverse the process. If might be possible, in theory, but even if it is, such a plan simply isn’t practical. In-situ resource utilization allows us to change that game. Instead of carrying all of that fuel with us, we can refuel at our destination.

Now, there are not (yet) gas stations full of rocket fuel sitting around on Mars or other planets that we can use to fill up our spacecrafts’ tanks, but there are significant resources available, if we can determine how best to use them. One of the better rocket fuels from a mass-thrust perspective is liquid hydrogen-liquid oxygen. Fortunately for us, those are some of the most abundant elements in the universe, particularly hydrogen. One form in particular can be easily captured, and that’s water: two parts hydrogen, one part oxygen. We can use electricity to split water into its constituent elements, and just like that, we have rocket fuel.

Alright, so it’s not really quite that simple, and accessing the (fairly significant) volumes of water-ice on Mars or even the Moon is a complicated endeavor in and of itself. But the point is, there are resources out there that we can use, if only we can determine how. Maybe that’s fuel, but it could also mean saving mass on things like life support, or even supplies. Radiation shielding, for instance: it’s heavy, because high atomic mass is needed to effectively block high energy radiation, so it’s challenging to bring enough with you. Instead, why not use the native materials? Going back to the camping analogy: would you rather carrying twenty pounds of water on your ten mile hike, or a six ounce water filter?

NASA acknowledges that they will need to leverage in-situ resources for their long-duration space missions, on which the Artemis program has put a renewed focus, but there are additional, legal complexities introduced by international law. Most significantly: the Outer Space Treaty, which states that no nation may claim territory on the Moon or other celestial bodies. By some interpretations, that means that NASA could run into legal trouble if it attempts to utilize resources on the Moon or Mars for its missions (although treaties have existed for half a century or more now, space law is a very young field, with almost no precedent, and so no one is quite sure how to interpret many of the provisions in the few pieces of international agreements there are). To circumvent this, NASA is turning to commercial partners. Click here to read their proposal.

If there is little to no precedent to know how space treaties affect government actors, there is even less to understand how it might affect commercial entities. In recent years, many nations and companies, the US included, have taken this to mean that commercial/private entities are not covered by provisions like the Outer Space Treaty, and could meaningfully utilize the resources of space (so far, no one has seriously worried about what happens if someone decides to lay an enforceable claim as a private entity to, say, Mars). The US in particular has been encouraging this shift towards the commercial and private sectors, most prominently with its commercial crew program after the retirement of the space shuttle (which I definitely have opinions about, but that’s a different topic).

Earlier this year, President Trump signed an executive order intended primarily to provide clarification to commercial entities on the US’s stance on their utilization of space resources, and to have NASA seek partnerships with such companies to further the progress of the Artemis program to return humankind to the Moon, and then go onward to Mars. With this latest announcement, NASA hopes that it can essentially offer a contract for a private entity to obtain lunar material, and then buy it from them. If this seems opaque and slightly shady to you, you might be right, but this is space law, and there are zero precedents and very limited enforceability. It’s the proverbial Wild West, and nations won’t challenge others’ actions if they are interested in doing the same thing.

This is only a very brief introduction to the concepts of in-situ resource utilization, and space law/policy. We’ll try to have a similar, educationally-themed post at least once per month, and I promise that they won’t all focus on space. There was a lot of material packed into this topic, so if you have any questions, or would like to discuss further, I encourage you to use the comments section, and I will be active there to further any discussion and attempt to provide answers to any questions you might have. Don’t forget to follow IGC Publishing to get the latest posts.