- SSC has completed a critical design review for two Epoch 2 missile warning satellite orbital planes
- BAE Space & Mission Systems is building 10 satellites as the program’s first Epoch 2 vendor
- The second Epoch 2 vendor selection is ongoing, with a contract award planned for early FY27
The U.S. Space Force’s Space Systems Command has completed the critical design review for the first two Epoch 2 orbital planes of its Resilient Missile Warning and Tracking Medium Earth Orbit program, advancing global missile tracking and battlespace awareness capabilities for the joint force and allies, the command said Tuesday.
The review marks the next phase of system design maturity for a program intended to expand missile threat tracking beyond the initial Epoch 1 constellation, with satellite assembly and testing set to begin next year.
What Milestone Did SSC’s Resilient Missile Warning and Tracking Program Reach?
The critical design review was completed five months after the preliminary design review, a.k.a. PDR, and 14 months after the program’s initial contract award in 2025, a pace SSC attributes to a modern acquisition approach built on digital engineering and proven technologies.
A combined government and industry team has advanced the Epoch 2 satellite system design following its preliminary design review, clearing the program to move into production and testing.
Program leaders attributed the progress to digital engineering tools that streamlined dynamic communication and resolved misalignments early. “To outpace today’s advanced threats, we are balancing speed with technical rigor to deliver global missile tracking capability to the warfighter,” said U.S. Space Force Lt. Col. Brandon Castillo, Epoch 2 system program manager.
Heather Tackett, Epoch 2 deputy system program manager, also noted that the joint team “has been in lockstep since PDR to mature this system design.”
Space vehicle assembly, integration, and testing are scheduled to begin next year under a development schedule set by a 2025 contract award. The program aims to field a resilient medium Earth orbit, or MEO, architecture to provide joint forces with actionable, real-time tracking data to counter maneuverable hypersonic missiles.
How Does Epoch 2 Expand on Epoch 1’s Missile Tracking Capabilities?
Epoch 2 builds on the resilient capabilities of Epoch 1 by enhancing missile threat tracking, adding a supplemental source of battlespace awareness and technical intelligence and advancing global coverage for the nation, warfighters and allies.
The new satellites will populate the first two Epoch 2 MEO orbital planes and build upon the two existing Epoch planes, which already include 12 satellites in orbit.
Together, the expanded architecture is designed to create a more robust, layered system for tracking missile threats worldwide. The buildout reflects SSC’s broader strategy of fielding capability in incremental phases rather than waiting for a single, fully mature constellation.
What Role Is BAE Space & Mission Systems Playing in Epoch 2?
The critical design review was completed in partnership with BAE Space & Mission Systems, the first of two vendors selected to build Epoch 2 satellites, bringing the program’s total to 10 new spacecraft. Source selection for the second Epoch 2 vendor remains ongoing, with a contract award planned for early fiscal year 2027.
BAE’s involvement in the missile warning mission extends beyond Epoch 2, as the company has separately supported the Space Force’s broader missile warning enterprise through payload and sensor hardware deliveries for related programs. Splitting the constellation across two vendors is intended to maintain competition and reduce schedule risk as the program scales.





