Developing space sensors for detection and tracking is the most significant challenge for the budding U.S. hypersonic missile defense effort, according to a new Center for Strategic and International Studies (CSIS) report.

The U.S. Space Force looks to develop and field the Northrop Grumman [NOC] Next Generation Overhead Persistent Infrared (Next-Gen OPIR) constellation, while the Space Development Agency (SDA) is working on its tracking and transport layers, to help defeat Chinese and Russian hypersonic missiles.

The nation’s current ballistic missile defense system (BMDS) is not well suited to tracking hypersonic missiles and intercepting them in their early phases, U.S. military officials have said.

“Sensing remains the central bottleneck to realizing a hypersonic area defense capability,” per the CSIS report. “The current BMDS is dependent on a relatively small number of surface-based radars to track incoming weapons. Constrained by the horizon, current BMDS sensors can only support counter-hypersonic engagements in the final phases of flight. The speed of hypersonic weapons leaves little time for computing a fire control solution, communicating with command authorities, and completing an engagement.”

“Supported by a low-latency communications network, elevated sensors of various kinds are necessary to resolve the range and mobility challenges associated with surface-based systems,” the report said. “Space-based sensors would enable a ‘birth-to-death’ tracking capability: the ability to follow a hypersonic weapon through the entirety of its trajectory. Such a capability would be critical for disrupting or defeating hypersonic weapons early in flight where interception is easier and follow-up shots are possible. A space-based sensor constellation would also aid in targeting adversary missile forces after launch and engaging traditional ballistic missile threats. These characteristics make space-based sensors essential for realizing a scalable and comprehensive missile defense architecture.”

The report said that Northrop Grumman [NOC] Defense Support Program (DSP) and Lockheed Martin Space Based Infrared System (SBIRS) satellites are able to detect “the hot plume of a hypersonic weapon’s rocket booster but may lack the sensitivity to track weapons through their glide phase of flight.”

The upcoming fiscal 2023 budget will reveal whether hypersonic missiles and hypersonic defense are priorities for DoD. The CSIS report said that the dollars for U.S. offensive hypersonic missiles, particularly stressed during the former Trump administration, have dwarfed hypersonic defense.

Missile Defense Agency (MDA) Director Vice Adm. Jon Hill said this month that the ongoing congressional funding impasse may set back the testing and contractor selection timetable for the hypersonic defense Glide Phase Interceptor (GPI) program under which MDA is considering bids from Raytheon Technologies [RTX], Lockheed Martin, and Northrop Grumman (Defense Daily, Feb. 3).