As advancements in space technology enable commercial entities, universities, and government research agencies to develop innovative methods for operating satellites at progressively lower altitudes, the U.S. Space Force is actively evaluating how these developments could be integrated into its future operations.
Over the past decade, the Space Force has strategically diversified its orbital assets. This shift has involved complementing its traditional architecture of large, highly capable, and expensive satellites in geosynchronous (GEO) and medium-Earth orbit (MEO) with proliferated constellations of smaller, more cost-effective satellites in low-Earth orbit (LEO). This strategy is evident in initiatives such as the Space Development Agency’s ongoing deployment of communications and missile warning satellites to LEO, and Space Systems Command’s exploration of options for positioning, navigation, and timing (PNT) capabilities within this orbital band.
This military transition to LEO has largely benefited from the pioneering efforts of commercial companies that first demonstrated the viability of deploying numerous small satellites to deliver reliable services to their customers. Now, as the broader space industry increasingly focuses its attention on even lower altitudes—a region referred to as very low-Earth orbit, or VLEO—the Space Force is considering its own potential operational footprint in this emergent domain.
While the service has not yet finalized any decisions regarding the launch of satellites into VLEO, Deputy Chief Science Officer Gillian Bussey has characterized VLEO as a significant emerging area of interest for the Space Force. “Fundamentally, when we look out to the future force, there is a place for VLEO,” Bussey stated to Air & Space Forces Magazine. “I can see it fitting into the overall architecture, but the question is to figure out exactly how and what.”
The space community generally defines VLEO as the region approximately between 150 and 350 kilometers above Earth, though some interpretations may extend this range slightly. Conditions within this altitude band can vary substantially, but historically, space operators have largely avoided prolonged operations in VLEO due to a range of environmental challenges. The predominant presence of atomic oxygen in VLEO makes the environment highly corrosive to most satellite materials and components. Furthermore, the residual atmospheric density at these altitudes generates significant atmospheric drag, necessitating advanced propulsion solutions for satellites to maintain their orbits. This density also makes VLEO satellites particularly challenging to track reliably from Earth.
Despite these operational hurdles, flying at lower altitudes offers distinct advantages. These include faster communication and data transmission speeds due to reduced signal travel time, more precise positioning, navigation, and timing (PNT) services, and the capability for higher-resolution imagery, whether sensors are observing ground-based events or monitoring activity in higher orbits. VLEO satellites could also play a crucial role in enhancing the Pentagon’s Golden Dome program, which aims to augment existing missile warning, tracking, and defense capabilities, and potentially even serve as space-based interceptors.
Even the extreme conditions prevalent in VLEO present certain benefits. The region is often described as “self-cleaning” because the intense atmospheric drag causes orbital debris to naturally de-orbit within weeks, significantly reducing the long-term hazards associated with space junk that accumulate in LEO. The same atmospheric density that creates drag also partially absorbs harmful radiation, thereby reducing the radiation exposure for VLEO satellites. This reduced exposure can translate into lower costs for satellite construction and procurement. Crucially, it also makes VLEO assets less susceptible to the devastating effects of a high-altitude nuclear detonation (HANE) in low-Earth orbit—a growing concern following reports in 2024 concerning Russia’s development of an on-orbit nuclear weapon capability.
These myriad advantages have spurred a significant resurgence of interest in VLEO in recent years, both from the commercial sector and government entities. Another substantial driving factor is the strategic activity of China, which has demonstrated clear intentions to establish its own satellite presence in this domain. China’s state-run aerospace industry has announced plans to launch a remote sensing constellation into VLEO by 2030 and has also established an industrial alliance dedicated to coordinating research and setting standards for operations within the region.
While the United States has not yet committed to a similar large-scale VLEO deployment, Western companies and defense agencies have been actively funding research and demonstration missions. These efforts seek to gain a deeper understanding of how the harsh VLEO environment impacts satellite performance, to test potential mitigations against environmental degradation, and to validate the projected capability enhancements. Among the innovations being explored are satellite designs engineered to minimize drag, high-power solar arrays optimized for VLEO, new materials developed to withstand the corrosive effects of atomic oxygen, and air-breathing electric propulsion systems designed to enable longer-duration missions at harsher VLEO altitudes by using the trace atmosphere as propellant.
Bussey noted that many of these ongoing efforts are promising, and if successfully demonstrated, could significantly accelerate momentum towards military VLEO operations. She also mentioned that her office has received inquiries about VLEO from both Congress and the White House over the past year, which has fostered increased internal discussion within the Space Force. While full, proliferated constellations in VLEO are considered longer-term projects requiring substantial further investment and understanding, Bussey emphasized that decisions regarding the operationalization of such capabilities fall outside her office’s direct purview. However, she underscored the Space Force’s critical need to thoroughly understand the cost-benefit trade-offs of operating in VLEO and to determine the most suitable altitudes for specific key missions.
“The complicated trade space between altitude and cost and numbers of satellites, it needs to be explored within the Space Force when we look further out to incorporating VLEO into the larger architecture,” she explained.
Despite the long-term considerations for extensive VLEO constellations, Bussey suggested that the Space Force could potentially leverage VLEO in the near term for rapid reconstitution purposes. The service has dedicated the past three years to refining its tactical responsiveness, demonstrating the capacity to quickly order and launch payloads on short notice—either to replace a degraded satellite or to augment existing capacity in response to a developing threat. Reconstituting assets in VLEO would significantly enhance resilience, and the typically smaller size and lower cost of VLEO satellites could provide the service with a wider array of launch options.
“You can use a lot of [commercial-off-the-shelf] components and can be ready to go if something happens and we need to reconstitute,” she said, further adding that “with minimal science and technology investment, the Space Force, if it chooses, can develop a rapid reconstitution capability to enable continued space operations post-[high-altitude nuclear explosion] or massive debris events using VLEO.”
Bussey highlighted a particular concern for the Space Force: the prospect of China having access to backup capacity in VLEO during a catastrophic event that compromises access to LEO, while the U.S. does not. “The Space Force’s responsibility is to secure our interests in, to, and from space, and that includes all regimes of space where those interests need to be protected,” Bussey asserted. “China is investing in VLEO… I think it creates an unacceptable asymmetry for the United States if China is able to reconstitute and use space, but we are very limited in our ability to.”
Why This Matters
The U.S. Space Force’s serious consideration of Very Low-Earth Orbit (VLEO) marks a pivotal moment in the evolution of national security space operations. This shift is not merely about exploring a new orbital band but represents a strategic imperative driven by technological innovation, global geopolitical competition, and the increasing vulnerability of existing space assets. Operating in VLEO offers distinct advantages that could redefine military capabilities, providing unprecedented data resolution, faster response times, and enhanced resilience against threats ranging from cyberattacks to high-altitude nuclear detonations. For the United States, mastering VLEO is crucial for maintaining its strategic advantage in space, ensuring critical national security functions like missile warning and precision navigation can continue even in a contested environment. Furthermore, the active pursuit of VLEO capabilities by nations like China underscores the urgency of this endeavor, framing it as a critical area for preventing a potential military asymmetry that could have profound implications for global stability and deterrence. This initiative will drive significant investment in advanced materials, propulsion systems, and satellite design, fostering innovation across the space industry and potentially creating new economic opportunities. Ultimately, how the Space Force integrates VLEO into its architecture will directly impact national security, technological leadership, and the future balance of power in the space domain.
Very Low Earth Orbit (VLEO), typically defined as altitudes below 450 kilometers, is emerging as a critical frontier for space operations, attracting significant attention from both defense organizations and private industry. While posing substantial engineering challenges due to its unique environmental conditions, VLEO offers distinct advantages for applications ranging from high-resolution imaging to enhanced communication and defense capabilities.
Traditionally, satellites have operated in Low Earth Orbit (LEO), generally above 500 kilometers, to minimize atmospheric drag and extend operational lifespans. However, the closer proximity of VLEO to Earth’s surface presents a compelling case for missions requiring exceptional detail and reduced signal latency. This includes advanced Earth observation, surveillance, and potentially more resilient communication networks.
Historical Precedent and Evolving Challenges
Operating in lower regions of space is not entirely novel. Some of the earliest national security space programs, such as the Corona program, demonstrated the utility of VLEO. A joint effort by the U.S. Department of Defense (DOD) and the intelligence community, Corona flew 145 surveillance missions between 1959 and 1972 at an altitude of approximately 185 kilometers (100 nautical miles). These satellites captured images, primarily of Soviet missile complexes and nuclear weapons storage sites, and delivered film cartridges to Earth via parachuted capsules. While successful, these missions were short-duration, typically lasting between one and 19 days.
Today, military operations continue to utilize VLEO for specific, short-term purposes, such as testing ballistic and hypersonic missiles, and operating spaceplanes like the X-37B. However, as Jonah Colman, a portfolio lead with the Air Force Research Laboratory’s space warfare directorate, points out, the current focus is on developing technologies for *sustained* operations in VLEO, which presents a different set of challenges than the historical short-duration flights.
The VLEO environment is inherently more extreme than higher LEO altitudes. The primary concerns include significantly increased atmospheric drag, the corrosive effects of atomic oxygen, and unpredictable space weather conditions. For instance, a satellite operating at 700 to 1,000 kilometers might experience a 3 percent reduction in its total lifetime due to drag. However, at 400 kilometers, drag could diminish a spacecraft’s service life by double-digit percentages. As altitudes decrease further, satellites could lose half, two-thirds, or even three-quarters of their expected operational lifespan. Understanding these environmental cycles and their timescales is crucial for designing resilient VLEO spacecraft.
Air Force Lieutenant Colonel William Bussey, a branch chief in the Space Force’s Space Warfighting Analysis Center, emphasized that future operations will require a careful balance between the benefits of closer proximity and the substantial propulsion and power necessary to sustain satellites in the face of intense drag. This trade-off is a central focus of current research and development efforts.
Innovations for Sustained VLEO Operations
Both industry and government agencies are actively exploring and demonstrating technologies aimed at enabling longer-duration missions in VLEO.
Colorado-based startup Albedo Space, for example, launched its Clarity-1 satellite experiment last year with the goal of proving that sustained VLEO operations are feasible and can deliver high-quality imagery more affordably than traditional, multibillion-dollar government spy satellites. Although Albedo lost contact with Clarity-1 after nine months due to a radio issue, the satellite successfully maneuvered from LEO to VLEO and provided data indicating it could operate within VLEO’s extreme conditions for up to five years. It successfully captured both visual and thermal imagery, demonstrating the potential for enhanced Earth observation capabilities from this low altitude. The company is now upgrading its satellite bus with a higher power configuration, a new radio, and addressing component issues encountered in orbit, with plans to launch a second mission, Vicinity-1, next year.
Another groundbreaking initiative is the Defense Advanced Research Projects Agency’s (DARPA) Otter program, a collaboration with Redwire and CUA Aerospace. This program aims to demonstrate air-breathing electric propulsion in VLEO. Counteracting drag typically requires substantial thrust and power, often supplied by large solar arrays and on-board fuel. However, traditional large solar arrays can increase drag, and the fuel required for sustained missions becomes impractically heavy.
DARPA’s innovative approach uses low-density atmospheric air as a propellant for the thruster, designed by CUA Aerospace, thereby eliminating the need for an on-board fuel source. The spacecraft, based on Redwire’s Sabresat platform, incorporates a flexible solar array configuration specifically designed to minimize drag while powering the electric propulsion system. Michael Mulqueen, a program manager in DARPA’s tactical technology office, highlighted the transformative potential: “With air-breathing propulsion, you’ll never run out of propulsion, so that extends your mission life greatly.” The full Otter mission is slated for launch in fiscal year 2028, with plans for at least one year of operation. A short-duration mission, lasting less than 24 hours, will precede it in late 2027 to test the air-breathing technology. Despite progress, Mulqueen acknowledges significant technical risks, as much of this technology is unprecedented and still undergoing ground testing and design maturation.
Industry’s Inflection Point
Industry leaders anticipate a rapid acceleration in VLEO adoption, with commercial ventures potentially paving the way for government operations. SpaceX is a prominent example, having received Federal Communications Commission (FCC) approval in early October for a 15,000-satellite constellation operating between 326 and 335 kilometers, with full deployment planned by 2035. SpaceX has also begun moving some of its existing Starlink satellites from their initial altitude of approximately 550 kilometers to below 480 kilometers, a move aimed at reducing collision risks and facilitating deorbiting at the end of their operational lives.
Spence Wise, senior vice president of business development at Redwire, views this shift to VLEO as a natural progression of the government’s strategy to disaggregate missions and build resiliency into its space architectures by leveraging Low Earth Orbit. He suggests the industry is already at an “inflection point,” observing strong demand and interest from both U.S. and European governments to move beyond investigation to full-scale buildouts.
Topher Haddad, CEO of Albedo, predicts that as VLEO technology proves its capabilities and more satellites demonstrate sustained flight, the performance benefits will make it increasingly appealing compared to traditional LEO solutions. He believes that VLEO solutions will increasingly compete with LEO solutions, meeting requirements in a “holistically better way” and leading to greater adoption in the near future.
Why This Matters
The race to master Very Low Earth Orbit holds profound implications across national security, commercial innovation, scientific research, and global competitiveness. For national security, sustained VLEO operations promise unparalleled surveillance capabilities, offering higher-resolution imagery and reduced latency, which can be critical for intelligence gathering, target identification, and missile defense. This proximity could enable more precise and timely responses to emerging threats, fundamentally altering the landscape of strategic deterrence and battlefield awareness. It also allows for the development of disaggregated satellite architectures, making space assets more resilient against attack by distributing capabilities across numerous, smaller, and potentially less expensive platforms.
Commercially, VLEO opens doors to a new generation of remote sensing and communication services. Companies like Albedo envision providing high-quality, actionable Earth observation data more affordably and frequently, benefiting sectors from urban planning and agriculture to disaster response and environmental monitoring. The ability to field smaller, more numerous satellites at lower costs could democratize access to sophisticated space-based services, fostering economic growth and new business models. Furthermore, advances in VLEO propulsion and materials science could trickle down to other industries, accelerating innovation in aerospace engineering and beyond.
Scientifically, sustained access to VLEO creates unique platforms for atmospheric research, allowing instruments to study the upper atmosphere, space weather, and their interactions with Earth’s environment with unprecedented detail. This could lead to a deeper understanding of climate change, ozone depletion, and the behavior of the ionosphere, directly impacting weather forecasting, communication reliability, and fundamental physics research.
Finally, the successful development and deployment of VLEO technologies will be a critical determinant of a nation’s leadership in the burgeoning space economy. The country or consortium that effectively overcomes the technical hurdles of VLEO will secure a significant strategic and economic advantage, influencing international standards, supply chains, and future space governance. This makes investments in VLEO not just about technology, but about securing future prosperity and global influence.