The US Space Development Agency (SDA) launched the first 10 of its 28 Tranche 0 satellites on 2 April using a Space X Falcon 9 Heavy reusable rocket. The launch was the first of two Tranche 0 launches with the second coming in June. In total Tranche 0 will place 20 data transport satellites that will use laser communications (also referred to as “optically connected”) and eight optically connected missile warning and tracking satellites. Optical communications reduce latency of communications and also offer increased security and bandwidth.
The Low-Earth Orbit (LEO) constellation is part of a broader effort to increase resilience of the US Department of Defense’s space based C4ISR network that will see hundreds of small satellites paced largely in LEO for data transportation and missile tracking. Traditionally, US space based C4ISR relies primarily on expensive satellites in higher orbits, which have increasingly come to be seen as vulnerable to a growing range of robust, varied, and diffused counter-space capabilities.
Specifically, Tranche 0 is designed to demonstrate the feasibility of key components:
- low latency data connectivity
- Beyond line of sight targeting
- Missile warning / missile tracking
- On-orbit data fusion
- Multi-phenomenology ground-based sensor fusion
In comments two days after the launch, Derek Tournear, SDA’s director, highlighted ground station vulnerability as another risk to the resilience of even proliferated C4ISR architectures in space against the increasingly robust, varied, and diffused counter-space capabilities. According to Tournear, “common mode failures [such as cyber-attacks] can take out all your satellites from the ground systems, then you can’t proliferate your way out of that–so that’s a major concern.”