SpaceNews : Why the U.S. shouldn’t simply race to Lagrange points 

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From the first satellite in orbit, to the first human in space, to the first steps on the moon, the United States government has always framed space exploration as a race. As U.S.-China space competition intensifies, so too does our American instinct to reach the next first. The Earth-moon Lagrange points may be next. In 2024, the U.S. House Select Committee on the China adopted the most definitive U.S. guidance yet on these special locations in cislunar space: “ensure that the United States is the first country to permanently station assets at all Lagrange points,” as part of a broader strategy to “counter [China’s] malign ambitions in space.” 

However, Lagrange points lack the strategic first-mover advantage of terrestrial “high ground.” There are no dramatic landings or above-the-fold photographs for these invisible points in the vacuum of space, nor can states meaningfully deny access or monopolize resources by arriving first. Because the operational zones for Lagrange points are so astoundingly large, Lagrange points are better understood as open commons rather than contested terrain, which means that the U.S. is unlikely to exclude other actors by arriving first, and vice versa. As former NASA Associate Administrator Bhavya Lal argued in a recent SpaceNews editorial, U.S. space policy must, “distinguish between symbolic milestones and strategic ones,” which is why the U.S. should prioritize the Earth-moon Lagrange points for their intrinsic strategic value rather than merely racing to reach them first. 

Understanding why the “high ground” analogy fails and why Lagrange points lack a first-mover advantage starts with the underlying orbital mechanics. Everything in space is constantly moving in an ever-changing choreography that makes most points in cislunar space unstable. Satellites cannot remain in place without expending precious fuel. However, two-body systems such as the Earth-moon system produce special locations — Lagrange points — where the gravitational forces combine perfectly such that satellites can theoretically maintain position without using fuel. 

To illustrate, consider how a satellite orbiting Earth would be affected by the gravity of the Earth and the moon, which orbits 384,000 kilometers (238,600 miles) from Earth (Figure 1). A satellite inside the moon’s orbit is pulled outwards from Earth, slowing its orbit; a satellite outside the moon’s orbit is pulled inwards towards Earth, speeding up its orbit. If those satellites are perfectly placed, then the gravitational forces combine such that the satellites orbit at the same rate as the moon and therefore keep the same position relative to the moon. In theory, satellites at Lagrange points don’t need fuel to remain in position for the same reason that the moon itself doesn’t require fuel to orbit Earth: Gravity does all the work.

Every two-body system contains five of these special Lagrange points: L1-L5 (Figure 2a). In the Earth-moon system, the L1, L2 and L3 points sit on the Earth-moon line, with L1 on the near side of the moon, L2 on the far side of the moon and L3 on the far side of the Earth. L4 and L5 sit directly on the moon’s orbit, with L4 and L5 located ahead and behind the moon, respectively. At each point, spacecraft can maintain their relative location in the two-body system while consuming minimal fuel, making these locations attractive for communication, observation and many other uses. For example, satellites at the Earth-moon L2 can continuously observe the lunar far-side. For a more in-depth dive into the physics of Lagrange points, readers can review this blog post I co-authored with an astrophysicist. 

But while the term Lagrange “point” is theoretically correct, it is practically misleading. In reality, spacecraft orbit and operate rather than stayat Lagrange points. The volume of usable space surrounding the Lagrange points is enormous, with orbital mechanics permitting entire “families” of orbits with varying geometries. For example, the James Webb Space Telescope orbits the Earth-Sun L2 point, oscillating between 250,000 kilometers and 832,000 kilometers from L2. For comparison, GEO satellites sit 42,000 kilometers from Earth’s center. The usable region around the Earth-moon L2 point is more than 10,000 kilometers across, a volume larger than Earth (Figure 2b). Therefore, spacecraft do not occupy Lagrange points any more than satellites in low Earth orbit occupy Earth.

Because the practically usable zones are so vast, the common view that Lagrange points are bottlenecks is misleading. A 2021 Atlantic Council report argues that “Lagrange points are a vital piece of space ‘real estate’; although space is large, a hostile power could dominate a Lagrange point and exclude other nations from using it.” What matters is not that space is large, but that the space of usable orbits surrounding Lagrange points is so large that exclusion would be difficult, if not impossible. While states could claim a mineral deposit on the moon by seizing an area several kilometers wide, the analogous “real estate” of a Lagrange point is an empty volume of space tens of thousands of kilometers in radius, large enough to hold nearly one dozen Earths. Lagrange points are more like open oceans where no single actor can meaningfully block access, even with military force. 

Therefore, the U.S. arriving first would not necessarily limit China’s ability to use Lagrange points, and vice versa. In theory, a space superpower could build a fleet capable of denying access to this entire volume of empty space. Indeed, U.S. naval doctrine dating back to Alfred Thayer Mahan emphasizes seizing command of the sea with an unrivaled navy. It may seem natural to extend this strategy to cislunar space. But dominating the world’s oceans and projecting naval power is based on controlling strategic chokepoints like straits and ports, geography that Lagrange points lack. Trying to deny access to Lagrange points would be like trying to blockade the entire Pacific Ocean. Not even Mahan intended for the navy to patrol every square kilometer of water, and that would still be easier than contesting every cubic meter around a point hundreds of thousands of kilometers from Earth. The sheer size of Lagrange points would make any such effort prohibitively expensive and politically unfeasible, especially when weighed against the opportunity cost of funding other space programs. 

Additionally, the number of usable orbital slots around Lagrange points is unlikely to run out in the foreseeable future. With conservative spacing, the available set of orbits near the Earth-moon L1 and L2 points could accommodate at minimum hundreds of well-managed spacecraft, enough for any near-term use case. Researchers are still refining these capacity estimates, as the calculation isn’t a simple volume-to-volume comparison with geocentric orbits. While geocentric orbits already require airspace-like management to avoid collisions, Lagrange point regions will demand even more intensive coordination because spacecraft will likely use more diverse orbital geometries, which actually reduces the number of spacecraft any given volume can safely accommodate. Nevertheless, even accounting for this added complexity, scarcity is unlikely given the total usable volume. And so because states would have tremendous difficulty denying access to or monopolizing orbits around Lagrange points, the first-mover advantage is largely negligible. 

Consequently, open commons like Lagrange points would at most provide only norm-setting, infrastructure and standard-setting benefits to the first-mover. However, these attempts can be resisted or ignored. For example, after decades of American monopoly, China’s Beidou and Europe’s Galileo systems are challenging the U.S. GPS system’s role as the leading provider of global navigation services, showing that motivated and well-resourced competitors can effectively overcome first-mover advantages with enough investment. Similarly, although the U.S. is pushing forward with the Artemis Accords to establish key lunar norms on resource use, safety zones and much more, major spacefaring states including China have not and likely will never join. Thus, the U.S. should not discount these benefits, but they certainly shouldn’t drive U.S. cislunar policy alone. 

With Lagrange points, there is no “high ground” to seize, only a resource to harness. Whether it’s Lagrange points, the lunar south pole or Mars, simply beating China to these destinations misses the point. The U.S. also needs to create best-in-class communications, intelligence and logistics infrastructure to support space operations, foster a thriving commercial space industry and establish norms of behavior aligned with our values and interests. The real prize isn’t getting to Lagrange points first — it’s leveraging them to build a robust, winning space ecosystem. 

Maxwell Zhu is a MPP graduate student at the Yale Jackson School of Global Affairs specializing in space policy. He previously consulted for the U.S. Space Force. He received his BA in Physics and Government from Harvard University. 

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