WASHINGTON — The U.S. Space Systems Command announced Nov. 28 that two satellite designs — one by Millennium Space Systems and the other by Raytheon Intelligence & Space — passed critical reviews and will move into the next phase of development. 

Both companies designed medium Earth orbit (MEO) sensor satellites to detect and track hypersonic missiles, and are on schedule for a 2026 on-orbit demonstration, the command said.

The Space Systems Command’s announcement follows a Nov. 23 news release by Millennium Space about the company’s MEO satellite passing a critical design review. 

MEO satellites would add a new layer to the Pentagon’s missile-defense architecture to improve the detection and tracking of hypersonic missiles.

“The critical design reviews proved the sensor designs are mature and we can move from demo to development,” said Lt. Col. Gary Goff, program manager at SSC’s Space Sensing Directorate.  

Roger Cole, executive director of strategic systems at Raytheon Intelligence & Space, said Nov. 29 that the company used digital engineering-based models and demonstrations to show that the designs of elements — such as focal plane, electronics, firmware and the telescope — are ready for fabrication. 

“This approach reduced technical and schedule risk,” he said. 

Raytheon’s sensor payload is being developed at the company’s facility in El Segundo, California.

Space Systems Command plans to conduct another review in summer 2023 of both companies’ spacecraft designs, Goff said. “If successful designs are matured and proven, the program can then proceed into building multiple satellites,” Goff said, adding that the goal is to conduct two launches in late 2026.

In the demonstration, the payloads in MEO will track missile launches and hypersonic glide vehicles and will work in concert with current Space Based Infrared Systems (SBIRS) constellations operating in geosynchronous Earth and highly elliptical orbits. They will also be connected with the Space Development Agency’s Tracking Layer satellites in low Earth orbit.

Both Millennium Space and Raytheon Intelligence & Space have options in their contracts to produce up to three spacecraft each. The value of the development contracts was not disclosed. The Pentagon requested $139 million for MEO missile-warning satellites in the 2023 budget.

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...