JUST IN: On-Orbit Refueling a Top Priority for Space Force

The Space Force requires advanced refueling technologies to enable greater mobility of systems in orbit, service officials said Jan. 31.

U.S. Space Command leadership has called for a shift to what it calls “dynamic space operations,” moving away from static space systems to maneuverable satellites that can either move toward or away from potential threats. One obstacle to achieving the desired level of mobility is the limited amount of fuel a satellite can carry.

Brig. Gen. Kristin Panzenhagen, Space Systems Command’s program executive officer for assured access to space, said developing ways to refuel systems in orbit is key to achieving maneuverability in space and is considered an “immediate need” for the Space Force.

Space Systems Command in September stood up a servicing, mobility and logistics program office to address the demand signal from Space Command — as well as other mission partners such as Indo-Pacific Command and Transportation Command — to develop solutions for dynamic space operations, said Col. Joyce Bulson, the director of the new program office.

“All of these technologies and the things we're looking at are based on what others have already started doing,” Bulson said during a media roundtable. The Space Force has had “requirements for this mission area” for several years, “but we did not have a program office to coordinate activities and events,” and there are “a lot of organizations” — including the National Reconnaissance Office, Defense Innovation Unit, Air Force Research Laboratory and Naval Research Laboratory — “trying to get after those requirements, because now the threat is here.”

The goal is to avoid duplication of effort, she said. In terms of space mobility, “the easiest piece for us to get at is refueling for prepared clients … while our [science and technology] partners work on” the longer-term, “more challenging technology — so very closely partnered with AFRL … DIU, NRL for those types of things.”

In September, Space Systems Command awarded a $25.5 million contract to Astroscale U.S. Inc. to deliver a servicing vehicle prototype by 2026 that will provide refueling services to compatible satellites and allow them to remain on station and on mission.

That was followed by an announcement in January by Northrop Grumman that its Passive Refueling Module, or PRM, had been selected “as the first preferred refueling solution interface standard for use across [Space Systems Command] satellites.”

“The refueling interface system Northrop Grumman is developing includes elements to successfully dock and transfer fuel, as well as a refueling payload that handles fuel transfer,” a company release stated. “Future satellites could be designed with an interface like the PRM to receive fuel while in space.” Space Systems Command contracted with Northrop Grumman to fly the PRM on an operational mission and awarded the company the Geosynchronous Auxiliary Support Tanker contract to begin development of a refueling tanker and associated technologies to deliver fuel in space, the release added.

Bulson noted that “there are other refueling ports that we're looking at and that we have on contract,” and the PRM is just the first one Space Systems Command’s Space Systems Integration Office has reviewed and recommended “as one of the options for refueling ports.”

“We're working with other partners to evaluate their designs and figure out what's the best process to get those under review for the larger Space Force community … there has not been a downselect or decision on [a] refueling port for our spacecraft,” she said.

Beyond refueling, the command is looking at other ways to give space systems more mobility, including a solution “kind of like a backpack or a jet pack” that can be connected to “an existing satellite to give it more propulsion, whether it's not designed to have sufficient thrust or if it’s out of propellant,” Panzenhagen said.

Bulson said her office is looking to expand its general servicing capabilities such as providing satellites more resiliency and extending their service life, as “refueling isn't the only life limiter for a spacecraft and not the only thing that can be targeted from a threat perspective.”

“It’s definitely a community of all of us coming together with these great activities and projects that have been started,” with the goal now to put them all “together into a roadmap so that our efforts are aligned,” Bulson said. “From what we've seen with our past engagements with our partners, fortunately we're all working on different areas in servicing, mobility and logistics … and just where do those feed into the roadmap based on dynamic space operations, addressing the threat, resiliency and life extension?”