The Space Force is requesting prototype proposals for space-based interceptors that can destroy a missile during the midcourse phase of flight, on top of its previous efforts to develop interceptors that take down missiles in their boost phase.
Both kinds of interceptors would be part of the Pentagon’s Golden Dome missile defense architecture, which is being designed to protect the U.S. from a range of high- and low-end missile threats.
The Dec. 7 notice for midcourse interceptors is light on details but says the prototype effort is focused only on kinetic solutions rather than nonkinetic systems that use directed energy to intercept a missile. Offers are due Dec. 19.
Space-based interceptors present one of Golden Dome’s bigger technical lifts. The Space Force has already awarded its first contracts for them in November, focusing on boost-phase interceptor prototypes. Speaking Dec. 6 at the Reagan National Defense Forum, Golden Dome Director Gen. Michael Guetlein said the service awarded 18 contracts using Other Transaction Authorities under that effort.
Separately, the Missile Defense Agency on Dec. 2 identified more than 1,000 companies eligible to compete for its Scalable Homeland Innovative Enterprise Layered Defense effort, or SHIELD. While the contract isn’t solely devoted to Golden Dome, it will issue task orders for prototyping and experimentation efforts that are linked to the larger program.
The technology behind space-based interceptors has been demonstrated through past efforts like the “Brilliant Pebbles” and the Strategic Defense Initiative, but it still new and requires maturation. The bigger challenge, Guetlein said at the Reagan Forum, is scaling that technology and making it affordable.
Achieving that, the general said, will require a change to the department’s “warfighting culture” that demands exquisite, highly lethal kit with such a high cost that the Pentagon can’t afford to buy it in large numbers.
“When we start talking about things like space-based interceptor, I’ve got to switch that equation on its head,” he said.” I’ve got to have high magazine depth, low cost per shot. How do I do that? We’re going to have to tap into industry innovation and bring it to bear to solve those problems.”
President Donald Trump has said he expects Golden Dome to cost $175 billion over the next three years, but experts have said that price will likely grow depending on how many space-based interceptors the department expects to need for U.S. coverage. The American Enterprise Institute, a Washington think tank, estimated in a September report the 20-year cost could range anywhere from $252 billion to $3.6 trillion.
Kathy Warden, CEO of Northrop Grumman, said during the panel it will take “a whole of government and industry approach” to determine the right design for SBIs that can be fielded “aggressively” and in significant numbers.
“The design has to not only be to develop a system,” she said. “It has to be to develop a system that can scale and scale affordably.”
Cost is also a “huge concern” for Congress, according to Sen. Deb Fischer, R-Neb., who was also on the panel. Making sure Golden Dome is adequately funded to meet homeland defense requirements will demand close coordination between Congress and the Pentagon, she said.
“We have to be able to know what we need and prioritize that,” Fischer said. “And I think those decisions are becoming clearer for those of us in Congress when we work with the department and with the military and really get the information there.”
Lawmakers included provisions in the fiscal 2026 National Defense Authorization bill aimed at fostering transparency on the program. In a compromise version of the bill that is expected to be voted on by the House on Dec. 10, members of Congress call for an annual report on Golden Dome’s architecture, cost, schedule, test plans, and operational concepts, among other details.
The bill also directs that until Golden Dome is fully operational, the Defense Secretary must brief Congress quarterly on the program’s progress.
