The U.S. Space Force is moving forward with its next-generation satellite constellation, known as RG-XX, which will monitor objects in geosynchronous orbit. In a significant shift in strategy, the service has mandated that these new space domain awareness satellites must be capable of on-orbit refueling, a first for a major constellation of this kind.
This requirement, emphasized by military leaders, aims to increase the longevity and maneuverability of critical space assets. The service plans to release a draft request for proposals by the end of 2025, signaling a move toward leveraging commercial technology for national security missions.
Key Takeaways
- The Space Force's new RG-XX satellite constellation will replace the current Geosynchronous Space Situational Awareness Program (GSSAP).
- A mandatory requirement for the new satellites is the capability for on-orbit refueling to extend their operational lifespan.
- The program will utilize commercially available technologies from multiple vendors, a shift from traditional defense procurement.
- This multi-vendor approach presents a logistical challenge, as different satellites may use incompatible fuel types.
- A draft request for proposals (RFP) is expected by the end of 2025.
A New Era for Space Asset Management
The United States Space Force is fundamentally changing how it acquires and maintains its satellite systems. The upcoming RG-XX program, designed to provide advanced space domain awareness, will replace the aging GSSAP constellation. These new satellites will be stationed in geosynchronous orbit (GEO), approximately 36,000 kilometers above the Earth, to monitor other objects in that critical orbital band.
The most significant change is the mandatory inclusion of on-orbit refueling capabilities. This decision was driven by a direct request from U.S. Space Command, which has long advocated for more dynamic and sustainable space assets. Maj. Gen. Stephen Purdy, a key acquisition official, confirmed the non-negotiable nature of this feature.
"It absolutely has to have a refueling requirement. I mandated that [and] was very militant about that, to be blunt, because U.S. Space Command has been very open about that desire," Maj. Gen. Stephen Purdy stated at the Air, Space and Cyber conference.
Refueling in space allows satellites to perform more maneuvers without depleting their finite onboard fuel supply. This extends their operational life and provides greater flexibility to respond to emerging threats or reposition for better surveillance.
Embracing Commercial Innovation
The RG-XX program also marks a major pivot in the Space Force's acquisition strategy. Instead of a single, massive, and expensive government-led development program, the service will purchase satellites and payloads from a pool of commercial vendors. This approach is intended to be faster and more cost-effective than traditional procurement methods.
By leveraging the innovation already present in the commercial space industry, the Space Force aims to deploy a more resilient and technologically advanced constellation. The plan is to have multiple companies contribute to the network, which will be owned and operated by the military.
Background: The GSSAP Mission
The current Geosynchronous Space Situational Awareness Program (GSSAP) consists of a constellation of satellites that drift above and below the GEO belt. Their primary mission is to track other satellites and space debris, providing crucial data that helps protect high-value U.S. assets like communication and missile-warning satellites. RG-XX is designed to be the more capable successor to this system.
This multi-vendor model, however, introduces a unique set of challenges, particularly concerning the new refueling requirement.
The Refueling Conundrum
While sourcing satellites from different companies promotes competition and innovation, it also creates a complex logistical problem. Different manufacturers often use different types of propellant and refueling ports for their satellite platforms.
"The whole intent of the market for this contract will be multiple winners in the end game, and I will have multiple different competitors actually flying," Purdy explained. "As it turns out, they’re all probably going to fly different fuel, and so how do I refuel that? So now we’re thinking through that."
Potential Refueling Solutions
The Space Force is considering several options to address the diverse fuel types:
- Vendor-Provided Refueling: Each satellite provider could be required to supply its own compatible refueling spacecraft as part of its contract.
- Third-Party Services: The military could purchase refueling as a service from specialized commercial companies capable of handling multiple propellant types.
These considerations are now being integrated into the planning for the upcoming request for proposals. The goal is to establish a sustainable logistics framework before the first satellites are launched.
The Strategic Advantage of Longevity
The push for refueling is rooted in strategic patience and fiscal reality. While commercial satellites may be cheaper to produce, replacing them still involves a lengthy and complex funding process. According to Purdy, securing funds through the five-year Program Objective Memorandum (POM) process and then building and launching a replacement satellite can take many years.
"It’s too easy to say, ‘Hey, they’re gonna be really cheap, and I can just launch more cheap birds,’" Purdy noted. "The reality is, it’s gonna take me a number of years to POM for that... it would have been a lot faster if I just had a refueler up there to refuel it."
On-orbit servicing, including refueling and repairs, is seen as a cornerstone of future space operations. It transitions satellites from being disposable assets to sustainable, long-term platforms. This capability is especially important in the increasingly congested and contested environment of space.
On-Orbit Servicing Milestones
The Department of Defense has already explored in-space servicing. The Space Force has previously funded research and conducted experiments with commercial partners like Northrop Grumman and Astroscale US to test technologies for refueling, repairing, and repositioning satellites.
Next Steps for the RG-XX Program
With the core requirements established, the Space Force is preparing to engage with the industry. The release of a draft RFP by the end of 2025 will provide commercial companies with detailed specifications and allow them to submit their proposals for the RG-XX constellation.
After reviewing the industry responses, the service will make final decisions based on available budgets. The ultimate objective is to field a robust and numerous constellation as quickly as possible to enhance the nation's ability to monitor activities in geosynchronous orbit.
"My intent, bluntly, is just to buy as many as possible," Purdy said. "I think this is clearly a mission need, where we need a lot as rapidly as possible, and that’s my mainline goal."
The RG-XX program represents more than just a technological upgrade. It reflects a strategic shift toward a more agile, commercially integrated, and sustainable approach to maintaining America's advantage in the space domain.