The moon is hot right now.
By some estimates, as many as 100 lunar missions could launch into space over the next decade — a level of interest in the moon that far surpasses the Cold War-era space race that saw the first humans set foot on the lunar surface.
With multiple nations and private companies now setting their sights on missions to the moon, experts say cislunar space — the area between Earth and the moon — could become strategically important, potentially opening up competition over resources and positioning, and even sparking geopolitical conflicts.
“We’re already seeing this competing rhetoric between the U.S. government and the Chinese government,” said Laura Forczyk, executive director of Astralytical, a space consulting firm based in Atlanta. “The U.S. is pointing to China and saying, ‘We need to fund our space initiatives to the moon and cislunar space because China is trying to get there and claim territory.’ And then Chinese politicians are saying the same thing about the United States.”
Both the U.S. and China have robust lunar exploration programs in the works, with plans to not only land astronauts on the moon but also build habitats on the surface and infrastructure in orbit. They are also not the only nations interested in the moon: South Korea, the United Arab Emirates, India and Russia are among the other countries with planned robotic missions.
Even commercial companies have lunar ambitions, with SpaceX preparing to launch a private crew this year on a tourism flight in lunar orbit, and other private companies in the U.S., Japan and Israel racing to the moon.
Increased access to space — and the moon — comes with many benefits for humanity, but it also raises the potential for tensions over competing interests, which experts say could have far-reaching economic and political consequences.
“During the Cold War, the space race was for national prestige and power,” said Kaitlyn Johnson, deputy director and fellow of the Aerospace Security Project at the Center for Strategic and International Studies. “Now, we have a better understanding of the kind of benefits that operating in cislunar space can bring countries back home.”
Though definitions sometimes differ, cislunar space generally refers to the space between Earth and the moon, including the moon's surface and orbit. Any nation or entity that aims to establish a presence on the moon, or has ambitions to explore deeper into the solar system, has a vested interest in operating in cislunar space, either with communication and navigation satellites or outposts that serve as way stations between Earth and the moon.
With so many lunar missions planned over the next decade, space agencies and commercial companies will likely be angling for strategic orbits and trajectories, Forczyk said.
“It might seem like space is big, but the specific orbits that we are most interested in get filled up fast,” she added.
Much of the increased activity in cislunar space owes to substantial decreases in launch costs over the past decade, with advancements in technology and increased competition both driving down the price of sending objects into orbit. At the same time, planetary science missions offered humanity a glimpse of the resources available in space, ranging from ice deposits on the moon to precious metals in asteroids, said Marcus Holzinger, an associate professor of aerospace engineering sciences at the University of Colorado Boulder.
“Once people started really thinking through that, they realized that that water-ice can provide substantial resources or enable the gathering or collection of resources elsewhere in the solar system,” he said.
Water-ice can, for instance, help sustain human colonies on the moon, or be separated into oxygen and hydrogen to fuel rockets on longer deep-space journeys.
With so much to gain, conflicts could emerge between nations or commercial entities.
In 2021, Holzinger co-authored a report titled “A Primer on Cislunar Space“ to help U.S. government officials understand the ins and outs of cislunar space. Holzinger said it wasn’t intended as a strategy document, but rather to inform those in the military and in government who are interested in cislunar operations.
That interest is apparent: Last year, the Space Force identified cislunar operations as a development priority, and in April established the 19th Space Defense Squadron to oversee cislunar space. In November, the White House released its own strategy for interagency research on "responsible, peaceful, and sustainable exploration and utilization of cislunar space."
The 1967 Outer Space Treaty, with more than 110 countries counted as parties, essentially declared that the exploration and use of outer space should benefit all of humankind and that no one country can claim or occupy any part of the cosmos. More recently, the Artemis Accords signed in 2020 established nonbinding multilateral agreements between the U.S. and more than a dozen nations to maintain peaceful and transparent exploration of space.
Holzinger said these agreements are “easy” when there aren’t tangible economic and geopolitical interests at stake.
“Now we’re sort of seeing the rubber hit the road, because all of a sudden there are potentially geopolitical interests or commercial interests,” he said. “We have to maybe come up with a more nuanced approach.”
Creating a sustainable and safe environment for cislunar operations will be critical, but the very nature of this area presents its own challenges.
Situational awareness in cislunar space, or the ability to know where objects are at all times, is tricky because of how expansive it is compared to the volume of space around Earth, including low-Earth orbit and geostationary orbit, said Patrick Binning, who oversees programs on space solutions to national security challenges at the Johns Hopkins University Applied Physics Laboratory.
“The volume of cislunar compared to the volume below geostationary orbit is 2,000 times more volume, so this is an enormous challenge to find things and keep track of things in that huge volume.” he said.
It's also harder to detect satellites and other spacecraft at such great distances from Earth, and in some cases, harder to predict their paths.
This is because objects in cislunar orbit are influenced by three different gravitational forces: the Earth, the moon and the sun, Johnson said.
“It’s a three-body system, which means that not all orbits are nice and circular or as predictable as those near Earth orbit,” she said.
Together, these factors could make it difficult to manage traffic in cislunar space, particularly if adversaries intentionally try to mask their activities there.
Yet if humans intend to establish a permanent presence on the moon, and venture beyond to Mars, it will be imperative to prioritize safety, sustainability and transparency, said Jim Myers, senior vice president of the civil systems group at The Aerospace Corporation, a federally funded research organization based in El Segundo, California.
"Those elements have to be there," Myers said. "Unless we do this in a very thoughtful way, unless we plan, we're going to run into all sorts of trouble."