The Missile Defense Agency (MDA) has announced it will deorbit two Space Tracking and Surveillance System (STSS) experimental missile warning satellites in the coming years and will focus on the development of next-generation Hypersonic and Ballistic Tracking Space Sensor (HBTSS) satellites to counter hypersonic missile threats, C4ISRNET reportedThursday.
“The combination of high speed, maneuverability and relatively low altitude of some of the emerging advanced missile threats makes them challenging targets for our current missile defense systems,” MDA stated in a January statement.
“HBTSS is needed, since we cannot populate the Earth and the oceans with terrestrial radars to meet this need. The ‘birth-to-death’ tracking that HBTSS can provide when integrated with terrestrial sensors will make it possible to maintain custody of missile threats from launch through intercept regardless of location.”
The experimental STSS has advanced the concept of space-based missile warning by demonstrating the ability to intercept a ballistic missile using orbital sensor data. However, depleted fuel reserves, outdated control systems and the launch of a new, ambitious missile warning satellite constellation on the horizon convinced the agency to end the STSS program.
The MDA has already awarded two contracts for the HBTSS prototypes, with L3Harris receiving $133 million and Northrop Grumman securing $155 million in support of the initiative. The new systems will work in conjunction with SDA’s tracking layer, a proliferated constellation of infrared sensors in low Earth orbit that can track hypersonic and ballistic threats.
The tracking layer will pass custody of missiles from satellite to satellite via a planned on-orbit mesh network as the missile fly. Custody will eventually be given to the HBTSS satellites, which have more advanced sensors that can provide targeting data to interceptors. HBTSS prototypes are expected to launch in 2023.