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Analysis of Current Law Governing Water in Space

Kody George


  • Gives an overview of why space water is important to the future of the United States and space exploration.
  • Discusses current law and how it may affect water use in space.
  • Suggests a possible basis for governing the future use of space water.
Analysis of Current Law Governing Water in Space
Christophe Lehenaff via Getty Images

In the past year, we’ve seen proliferating private space enterprises, new agreements on how states and private companies could use space resources, three different countries announcing plans to set up Moon colonies, and new data confirming that frozen water is present on the Moon. A basic framework for space law governing water use lies in the Agreement Governing the Activities of States on the Moon and Other Celestial Bodies (herein the Moon Treaty), the Outer Space Treaty (OST) of 1967, the Artemis Accords (the Accords), and international norms. These separate bodies of international law work together to describe how water on the Moon, Mars, and the rest of outer space will be governed. This article will give an overview of why space water is important to the future of the United States and space exploration, briefly discuss current law and how it may affect water use in space, and suggest a possible basis for governing the future use of space water.

Importance of Space Water

While liquid water is abundant on Earth, space water comes in the form of frozen particles trapped between soil, found in low volume brines in soil or ice sheets, or as water vapor that is thinly available in planetary atmospheres. Experiments and studies have confirmed the presence of water on the Moon, Mars, and comets. Because of the frozen nature of almost all water in space, it has to be mined rather than diverted or pumped. While more studies need to be done on the form and availability of space water, its importance is undisputed.

Water is essential to life. It is the key resource needed for a sustainable presence on an extraterrestrial body. In addition to being used to sustain life, in space water is looked at as essential to further exploration due to its ability to be used as fuel and the potential economic benefits it might provide. Water is made up of hydrogen and oxygen, which when separated, are highly combustible and can be turned into liquid rocket fuel. Water on the Moon could be mined and separated into its components to be used as fuel for ships going from the Moon to Mars or the Moon to an asteroid. It has even been proposed that if a suitable water source on Mars is found, it could be turned into fuel for a return trip to Earth.

The availability of water as a fuel and drinking source, on the Moon especially, could make it economically feasible for more projects and people to explore space. The gravity of Earth is about six times that of the Moon’s. In other words, the act of lifting one gallon of water a foot from the surface of the Earth is going to be around six times more expensive than lifting one gallon of water a foot from the surface of the Moon. Because of the potential cost savings lower gravity offers, the Moon is looked at as a potential launching pad to the rest of outer space. Water on Mars is looked at as the only viable way to create enough fuel for a return flight home. While mining space water represents high up-front costs, the long-term economic effect would be to drastically decrease the total cost of space exploration. Especially as private businesses continue to venture into the realm of space exploration, long-term economic costs are going to be a large consideration.

Space water is important because it has the ability to propel explorers and spacecraft from one body to another at a lower economical cost than coming to and from the surface of earth. The ability of water to essentially sustain an outpost of civilization by providing fuel and drinking water show why it is so important to the future of space exploration. It is a key to unlock the future of space.

The Moon Treaty

The Moon Treaty is a treaty that attempted to develop a framework for the use of the Moon and other celestial bodies “on the basis of equality” and “cooperation among States.” The Moon Treaty has not been widely adopted and has not been ratified by any countries that have achieved human space travel, therefore its contribution is limited to being a persuasive opinion on how space resources should be approached rather than being a binding agreement. With this limitation, the Moon Treaty’s greatest and most controversial contribution to the discussion of how space law should be established is the idea of cultural heritage. Cultural heritage is the notion that space belongs to all mankind and thus the resources found in space are for everyone, including future generations. Each international country, or state, should share in the costs and, especially, the benefits of resources taken in space. Individual state’s also bear all responsibility for ensuring actions of non-state actors based in their country are in accordance with the treaty. The idea of cultural heritage extends to smaller things, such as preserving the footprints of Neil Armstrong as humanity’s first steps on the Moon, to larger things such as the equitable distribution of minerals and water harvested. The way this central ideal would apply to water resources is that the international community would decide as a whole how to mine for water, where to mine for water, and the portion of resources allotted to each country. The wants and needs of each state actor, as well as future interests, would be accounted for. The international community would essentially hold all interstellar water sources in the public trust.

The Outer Space Treaty

The OST was signed near the beginning of the Cold War and is the central binding international treaty that discusses space water and mineral use. There are currently 111 countries party to the treaty, including all the major space powers, and an additional 23 countries that have signed but not completely ratified it. The OST does not allow appropriation or ownership of the Moon by states. Article II specifically prohibits “national appropriation by claim of sovereignty, by means of use or occupation, or by any other means.” This clause has been interpreted in various ways. Those who interpret it narrowly say it bans states claiming sovereignty but not state extraction of resources. It also does not prohibit individuals and businesses that are not state actors to claim ownership over portions of the Moon. The expansive interpretation of the OST is that businesses and nations do not own any resource they extract, they are owned by humanity collectively. The middle ground interpretation is that permanent occupation is not allowed but the mining and use of resources as well as temporary occupation is not prohibited by the treaty.

Controversies surround mining and using Moon water are centered around Article II but are shaped by other principles detailed in the OST. The OST grants freedom of use of the Moon, freedom of access, and the freedom of exploration. These additional freedoms are tempered by obligations, such as due regard to the corresponding interests of other state’s body and not to harmfully interfere with other’s activities.

If a state is mining water, the quantity they should mine might be limited by the duty of due regard to other states who might want to engage in mining activities. If a state is harvesting water in a prime location, how long can they mine there without other states considering the operation to be permanent? If a state is mining, can other states come and monitor their operations under the freedom of access and exploration principles or would the monitoring be considered harmful interference?

These lingering questions help demonstrate that there is no real consensus on how space resources should be governed. The OST is too broad to effectively manage space water. The only real consensus amongst states is that space resources are valuable and that each actor wants to use them in a way that grants the most benefit. To help define the OST, states have signed agreements and passed laws that further their interpretations.

Artemis Accords

The Accords were meant to build off of and further define the interpretation of the OST. Signed in October of 2020, the Artemis Accords are an attempt to agree to the peaceful use of resources on the Moon, Mars, and comets. The Accords are a collection of bilateral agreements that other countries have signed with the United States to define how the OST should be interpreted. The accords also act as a gateway to participation in the Artemis space program. The Accords are rooted in the OST and codify the United States’ interpretation of the OST in international law.

The most notable portion of the Accords is section 10, Space Resources. The section provides, “the extraction of space resources does not inherently constitute national appropriation under Article II of the Outer Space Treaty.” This narrow interpretation of the OST opens the door for the United States and other countries to mine and use water found in extraterrestrial bodies. This interpretation would also allow for the extraction and exclusive use of space water by state and private actors.

The largest criticisms of the Artemis Accords are that they push the United States’ space agenda and allow the privatization and commercialization of outer space through bilateral treaties rather than going through traditional international pathways. It is notable that neither Russia nor China have entered into the Accords. Many critics believe in some version of the principles laid out in the Moon Treaty––that Outer Space is the province of all mankind, not individual nations. They believe that using bilateral agreements to generate a consensus interpretation of an international treaty is a bully method of negotiation and harmful to the overall goal of peaceful space exploration. Most critics say that international negotiations should be attempted so that an agreement can be found that benefits all people.

While the accords have been criticized, they also give a clearer picture of the way the United States would operate on the Moon—by extracting and putting water resources to use. The accords represent the idea that some states and actors are planning on extracting water from the celestial bodies. As is often said, “possession is nine-tenths of the law.” The Accords show that the discussion might need to focus on what regime should govern state and private actors rather than on if the mined resources can be essentially owned by one party.

Future of Space Water Law

The future of water law in space is still unclear. Under the current United States’ view and the interpretation of the OST set forth in the Artemis Accords, it seems likely that a system similar to the western doctrine of prior appropriation or the Texas groundwater rule of capture is going to be the de facto system governing space water. Those who are first in time will be first in right and can drink or mine as deeply as they want until someone else comes along. Once another viable user arrives, the second appropriator could decide if they will honor the first party’s claims as a senior appropriator or if they will “stick their straw” in and take what they can get. Because of the technology gaps and difficulty in going to the Moon, the only real pressure many states could put on a nation mining space water would be on Earth. The threat of sanctions or war on Earth may be the catalyst to a different system. Alternatively, the threat of actual extraction of water in space by a single actor may be a catalyst for an international effort to create another workable system.

Due to the frozen nature of the water and the difficulty of extraction, a system modeled after Alaska’s Glacial Ice Harvesting statute may present the most common-sense system to governing space water. A system modeled after Alaska’s would look something like an international space agency issuing permits on the location of harvest, the amount of frozen water that could be mined and harvested, and the length of the permit. The Alaskan model is simple, but adequate because viable mining locations and actors are limited within Alaska. These constraints are similar to that on the Moon or Mars––limited viable extraction locations and actors. A very simple permitting system could be the start of a solution to a complex problem.

While the overall state of the law governing space water is still undefined, private companies and states with ambitious goals to establish a presence on the Moon and Mars seem to be in the driver’s seat on how space water will be used. Unless the international community comes together and creates a new treaty or defines how Article II of the OST should be interpreted, the current law is sufficiently ambiguous for actors to start mining and extracting water as soon as they figure out the economics and technology to do so.