The US Space Development Agency (SDA) has awarded Sierra Space a $798 million contract to manufacture 18 advanced missile warning and tracking satellites for the Accelerated Missile Defense Tranche 3 (AMDT3) Tracking Layer. The satellites, built on the company’s Horizon spacecraft platform, will provide continuous detection and tracking of ballistic, hypersonic, and other advanced missile threats. This contract expands Sierra Space’s participation in the nation’s evolving Golden Dome missile defense architecture, which integrates orbital sensors, command systems, and interceptor networks to enhance homeland protection. The satellites will work alongside additional spacecraft developed by other contractors, creating a resilient space-based surveillance layer capable of supporting rapid threat identification and missile interception.
