The Artemis II crew splashed down in the Pacific Ocean in April 2026, completing the first crewed lunar mission since Apollo 17. Artemis II was an extraordinary engineering achievement: a complex integrated flight test of the Orion spacecraft, the Space Launch System, and the deep-space mission-control infrastructure needed for a sustained lunar program. Among the crew was Jeremy Hansen, the first Canadian to fly to the Moon – alongside the first woman and first person of color to do so; the mission was, deservedly, a global event.
Legally speaking, this mission was a quiet one. It did not trigger any of the textual tensions that we find in the Outer Space Treaty. Artemis II did not land on the Moon. It did not extract lunar resources. It did not deploy hardware destined to sit on the lunar surface for decades. But the broader Artemis program advances incrementally, each mission reaching just a bit further than the last. Artemis I, in 2022, sent an uncrewed Orion around the Moon and back. Artemis II has now done the same with a crew aboard. Artemis III, planned for 2027, will rehearse the harder choreography: astronauts docking Orion with the (yet to be built) commercial landers from SpaceX and Blue Origin. Artemis IV, optimistically scheduled for “early 2028,” will return humans to the lunar surface for the first time since 1972. Artemis V and the missions beyond it would make landings routine, deliver a rover, and begin assembling a permanent base near the lunar south pole. It may even carry a nuclear reactor to the lunar surface. So, it is somewhere around Artemis IV and V that some of the textual tensions within the Outer Space Treaty could stop being hypothetical.
What are these textual tensions? Both the Vienna Convention on the Law of Treaties, and the customary international law it reflects, require that treaties be read as a whole. Yet reading the Outer Space Treaty as a whole reveals provisions that pull against one another. The text explicitly anticipates permanent lunar infrastructure: Article VIII guarantees that a state will “retain jurisdiction and control” over objects “landed or constructed on a celestial body,” while Article XII establishes reciprocal rules for visiting lunar “stations, installations, [and] equipment.” Paired with Article IX’s requirement that states act with “due regard” to avoid “harmful interference,” these provisions set up a complex dynamic. Together, they create a framework where a state places installations on the Moon, keeps them under its control, and expects others to stay clear (save for the pre-coordinated reciprocal visits), effectively carving out a protected, exclusive patch of the lunar surface. Yet Article II simultaneously dictates that celestial ground cannot be appropriated “by means of use or occupation.” Flags, remaining equipment, and bootprints - the Apollo program - raise this contradiction only faintly. A permanent base, drawing power from a fixed reactor and occupying the same ground for decades - the Artemis program - raises it loudly.
The Artemis Accords are a laudably proactive attempt to resolve some of these tensions. Section 11 of the Accords endorses the concept of “safety zones,” acknowledging the practical necessity of buffer areas around lunar installations to prevent harmful interference and mitigate risks to property and personnel. And Section 10 affirms that “the extraction of space resources does not inherently constitute national appropriation” as national appropriation would be prohibited by Article II of the Outer Space Treaty. As of May 2026, the number of signatories stands at 67, far surpassing the increasingly moribund Moon Agreement, which traverses many of the same issues.
The Accords are not a treaty, but simply a “political understanding.” Yet the position that the Accords stake out will likely acquire the weight of state practice over time, as the Artemis program progresses, solidifying its position within international space law. But the Accords are not the only game in town. Consider the Working Group on Legal Aspects of Space Resource Activities, established in 2021 by the Committee on the Peaceful Uses of Outer Space, and chaired by Prof. Steven Freeland. The Working Group is now in the final stretch of a five-year plan that aims to deliver, by 2027, a non-binding set of recommended principles for space resource activities. The most recent draft of these recommended principles, dated 28 April 2026, is heavily bracketed (a faithful reflection of the disagreements still in the room). But the resemblances between the Accords and the draft principles are hard to miss. Consider Section 10 of the Accords, as extracted earlier, against draft principle 2(C), which states that “[t]he extraction of space resources [in full compliance with these Principles] does not inherently constitute national appropriation.” The formula the United States and its partners wrote in 2020 has found its way, very nearly intact, into the Working Group’s current draft.
In both the Accords and the draft principles, the word “inherently” is doing some seriously heavy lifting by, in the time-honoured traditions of international legal drafting, covering a range of discordant positions. The fact that extraction is not inherently prohibited leaves the door open to such extraction being prohibited in certain conditions. And these conditions - the limits, safeguards and shared obligations that must travel with extraction before the international community will treat that extraction as lawful – remain up for debate. Consider a recent Chinese submission to the Working Group, which suggests that “[n]o State ... shall have the right to permanently occupy the in-situ space resources and the area in which the relevant in-situ resources are located to exclude other States ... nor shall they have the right to exclusive occupation and use of areas adjacent to their space resource activities not actually being used for scientific research and extraction.” This submission can be read as a critique of how Accords-style safety zones might operate in practice, without naming them expressly. For its part, Russia, although not itself a party to the Moon Agreement, has urged the Working Group to treat that treaty as “part of the existing international space law” forming, with the four other UN space treaties, “its solid foundation” - and to consider establishing an international body modelled on the International Seabed Authority.
The United States, in a March 2023 submission, restated a long-standing interpretive line: that the Article II prohibition “applies to the natural resources of celestial bodies only when such resources are ‘in place’ (in situ),” while Article I “recognizes the right of exploitation.” In its April 2026 statement to the Legal Subcommittee, Washington reiterated that view in nearly identical terms, while adding two points worth noting: that any Working Group output should be “high-level, non-legally binding principles,” and that “[d]iscussions about benefit sharing of resources that have yet to be successfully extracted and used on a large-scale basis are counterproductive.” These two milestones - successful extraction and large-scale usage - are, of course, many, many years away.
What we have here is a contest among interpretative communities. The Accords are one such community formed around one reading of the Outer Space Treaty. Russia and China seem to have formed another such community, pulling in a different direction. The Working Group is the venue where these two communities (and potentially others) meet. Whatever the Working Group produces will not necessarily resolve the contest between these communities. But its value may lie in setting the ground rules for that contest. Consider how the Declaration of Legal Principles, the product of negotiations in the early 1960s between the United States and the Soviet Union, established the rules for the Space Race - and made that contest about getting to the Moon first, rather than claiming it first.
However, agreeing to ground rules requires at least some degree of consensus. In this respect, there is an important thread along which the various interpretive communities appear to converge. This thread is science. Russia’s submission emphasizes that the Outer Space Treaty “prioritizes the use of outer space for scientific rather than commercial purposes.” China’s submission provides that scientific missions “shall be given more weight” where commercial and non-commercial activities must be coordinated. Canada, in a 2025 submission to the Working Group, notes that “[t]he release and exchange of scientific data is in the interests of and benefits all States,” and states that “Canada places particular emphasis on … the exchange of scientific data.” Even the United States, which resists a benefit-sharing framework in nearly the same breath, lists “open science” among the principles it considers worth common adherence. On much else these states disagree; on science we have the beginnings of consensus.
Fortunately, science lies at the heart of the Artemis program. Alongside the four astronauts, Artemis II flew CubeSatsbuilt by the space agencies of Germany, South Korea, Saudi Arabia and Argentina, together with a radiation experimentfrom the German Aerospace Center. Over the lunar far side, the crew spent their hours photographing impact craters and ancient lava flows for scientists waiting on the ground. None of these scientific activities required anyone to settle what “appropriation” means, nor the conditions on extraction. For now, science remains the most load-bearing common ground in international space law. Whether this nascent consensus can survive the transition from scientific exploration to permanent habitation remains to be seen as we look beyond Artemis II.
Jack Wright Nelson is an Assistant Professor of Law at Thompson Rivers University.
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