Los Alamos National Laboratory via Aerospace Projects Review
By Joseph Trevithick,
Published by The War Zone, 22 July 2025
Competition to supply parts of Golden Dome is heating up with Northrop Grumman stating they have begun ground testing orbital missiles.
Northrop Grumman is conducting ground-based testing related to space-based interceptors as part of a competition for that segment of the Trump administration’s Golden Dome missile defense initiative. Interceptors deployed in orbit are currently billed as a critical component of the overall Golden Dome plan, but actually fielding this capability presents significant technical challenges.
Kathy Warden, Northrop Grumman’s CEO, highlighted the company’s work on space-based interceptors, as well as broader business opportunities stemming from Golden Dome, during a quarterly earnings call today. Golden Dome is presently envisioned as a multi-part anti-missile architecture incorporating a swath of existing and future capabilities in space and within the Earth’s atmosphere, which will start entering into operational service by 2028. Golden Dome was originally dubbed Iron Dome before the name was changed earlier this year. It is also now being managed by an office that reports directly to the deputy secretary of defense.
“As we look to Golden Dome for America, we see Northrop Grumman playing a crucial role in supporting the administration’s goal to move with speed and have initial operating capability in place within the next few years,” Warden said today. “This includes current products that can be brought to bear, like IBCS [Integrated Battle Command System], G/ATOR [AN/TPS-80 Ground/Air Task Oriented Radar], Triton [drones], and programs in our restricted portfolio, just to name a few. It will also include new innovation, like space-based interceptors, which we’re testing now.”
“These are ground-based tests today, and we are in competition, obviously, so not a lot of detail that I can provide here,” Warden added. “It is the capability that we believe can be accelerated and into the time frame that the administration is looking for.”
Warden declined to respond directly to a question about how the space-based interceptors Northrop Grumman is developing now will actually defeat their targets. TWZ has reached out to the company for additional information.
The U.S. military itself seems to still be in the process of ironing out its requirements for space-based interceptors for Golden Dome. Earlier this month, the U.S. Space Force’s Program Executive Office for Space Combat Power, part of the Space and Missile Systems Center (SMC), put out a request for information (RFI) for details about how contractors might meet this need. The contracting notice lays out a general vision for a future space-based anti-missile capability that could include two types of interceptors, as well as supporting systems in orbit and back on Earth.
"The Space Force PEO Space Combat Power is conducting market research to identify Space Based Interceptor (SBI) capabilities to address the threat of attack by ballistic and hypersonic missiles. The purpose of this RFI is to identify existing space-based missile defense… pic.twitter.com/Gn8gSubMUj
— Dmitry Stefanovich (@KomissarWhipla) July 3, 2025
“Exoatmospheric SBIs [space-based interceptors] are designed to destroy targets in the boost and mid-course phases outside the Earth’s atmosphere (above 120 km), employing a kill vehicle (KV), guidance and navigation systems, communications, and propulsion for both initial engagement and terminal guidance maneuvers,” the notice explains.
“Boost phase” is a term that refers to the portion of flight for a ballistic missile, as well as highly maneuverable hypersonic boost-glide vehicles that use ballistic missile-like rocket boosters, right after launch, where they are slowest and most vulnerable. The bright plume of hot gas from the booster makes them easier to spot and track for an intercept attempt. It is also a decidedly short engagement window likely to occur well within an adversary’s territory, which presents a host of challenges.
The “mid-course phase” is the middle portion of a ballistic missile’s flight. Larger ballistic missiles typically travel in space, or at least in the very upper reaches of the atmosphere, during this phase.
“Endoatmospheric SBIs are designed to destroy targets within the Earth’s atmosphere (below 120 km), employing a KV, guidance and navigation systems, communications, and propulsion for initial engagement and terminal guidance maneuvers while accounting for atmospheric effects,” it continues.
SMC’s contracting notice does not include any more specific details about desired capabilities for the interceptors, including how they will find and prosecute their targets. It does raise the possibility of “several interceptor variants (multiple exoatmospheric and endoatmospheric variations from multiple vendors).”
“Terminal Guidance enables the SBI to acquire and track the target autonomously after weapon release from its host satellite, executing precise maneuvers during the final phase of flight to achieve a successful intercept,” it adds. “In-Flight Target Update provides the ability to modify the SBI’s target information while it is in flight, based on new sensor data or changes in the threat trajectory.”
Other key components of the planned space-based anti-missile system outlined in the contracting notice include interceptor-launching satellites, a Common Ground Element (CGE), and a Fire Control Element (FCE). The GCE and FCE are expected to leverage offboard sensor and communications capabilities, including distributed satellite constellations that are already in the process of being developed and fielded.
Plans for space-based interceptors have been a central, as well as controversial, part of the Golden Dome/Iron Dome initiative from the beginning. Interceptors in orbit were also a key element of the Reagan-era Strategic Defense Initiative (SDI), infamously dubbed “Star Wars” by its critics, which never came close to achieving its ambitious goals.
“It’s not just that we want space-based interceptors, we want them in [the] boost phase,” U.S. Space Force Gen. Chance Saltzman, chief of Space Operations, said during a live online interview with Defense One in March. “We want them to achieve their effects as far from the homeland. So they’ve got to be fast, they’ve got to be accurate.”
“I think there’s a lot of technical challenges,” Saltzman added. “I am so impressed by the innovative spirit of the American space industry. I’m pretty convinced that we will be able to technically solve those challenges.”
“We’ve got a pretty amazing space industrial base and I’m pretty sure they’re going to solve most of those technical problems,” he continued. “So, from that standpoint, I think it’s just about how fast you want to go, you know, how fast can we leverage the technology, and put it in place and test it, [and] get a demo out there so you can see what’s possible.”
At that time, Saltzman also pushed on criticism that the space-based interceptor component of Golden Dome would have a destabilizing impact through the weaponization of space. He highlighted the U.S. military’s top responsibility to defend U.S. citizens, as well as the development and fielding of threatening space-based capabilities by other countries, especially China and Russia. The Chinese and Russian governments are among those that have been very actively investing in ground-based anti-satellite weapons, as well.
“What I think we’re really recognizing is now space is a contested war-fighting domain, and that’s what’s new, not that the military is considering offensive and defensive operations,” Saltzman said. “Militaries always conduct offensive and defensive operations to contest the domains to meet military objectives. We just recently had to up our game, if you will, because space has become a warfighting domain.”
Larger questions remain about the overall Golden Dome plan, which is highly ambitious in scope and schedule, as well as total cost, which is already estimated to be in the hundreds of billions of dollars. When it comes to space-based interceptors and other assets in orbit, there are logistical concerns, including the space launch capacity just to get the host satellites into orbit, on top of the technical hurdles.
An open feud between President Donald Trump and Elon Musk, once close political allies, has highlighted the particular dependence America’s armed forces have on Musk’s SpaceX for space launch and other space services, as you can read more about here. That spat erupted publicly in June and continues to simmer. SpaceX had previously been seen as likely to take a leading role in various aspects of Golden Dome.
“The Trump administration is expanding its search for partners to build the Golden Dome missile defense system, courting Amazon.com’s Project Kuiper and big defense contractors as tensions with Elon Musk threaten SpaceX’s dominance in the program, according to three sources familiar with the matter,” Reuters reported just today. “Even before the spat, officials at the Pentagon and White House had begun exploring alternatives to SpaceX, wary of over-reliance on a single partner for huge portions of the ambitious, $175 billion space-based defense shield, two of the sources said.”
During today’s earnings call, Northrop Grumman’s CEO Warden highlighted the large financial windfalls that could come from Golden Dome, which are likely to drive significant competition across all elements of the initiative.
“I’m equally excited about Golden Dome for America, which is a new set of opportunities, very significant funding there, as you know, in the reconciliation bill, and our opportunity to pursue some of that work,” she noted.
The reconciliation funding bill she referred to, also known as the One Big Beautiful Bill Act, was signed into law earlier this month and includes nearly $25 billion for integrated air and missile defense efforts, many of which are tied to Golden Dome. The bill, which does not mention Golden Dome by name, notably includes $5.6 billion specifically “for development of space-based and boost phase intercept capabilities.”
Northrop Grumman is already among the competitors vying for the space-based interceptor portion of Golden Dome.
See: Original Article
