On Monday, the SDA awarded information technology firm L3Harris Technologies a $193.6 million contract and private space company Space Exploration Technologies Corp. (SpaceX) a $149.1 million contract, each to build four satellites with a wide field of view (WFOV) overhead persistent infrared (OPIR) sensor, which the SDA is calling “Tracking Layer Tranche 0.”
"The satellites will be able to provide missile tracking data for hypersonic glide vehicles and the next generation of advanced missile threats," SDA Director Derek Tournear said in a Pentagon release on Monday. He also told Space News on Monday that both firms are required to deliver their satellites by September 2022.
In June, Tournear said on a Missile Defense Advocacy Alliance broadcast that the first eight satellites would pioneer the concept of a WFOV sensor, as present missile early warning satellites use narrow fields of view due to their less sophisticated technology. This constellation will start out at 20 satellites after the first eight are proven, but could eventually grow to as many as 200.
As Sputnik reported, the existing Space-Based Infrared System (SBIRS) satellites are geared toward spotting ballistic missile launches, during which the rocket engines put out huge amounts of heat that stands out from the background temperature of the Earth. However, with the advent of hypersonic glide vehicles, which have short rocket burns compared to traditional ballistic missiles, this method makes it harder to spot their launch - and basically impossible to spot them once they “go cold” and begin their high-speed glide towards their target.
According to The Drive, SpaceX’s satellite will be derived from its Starlink project, envisioned as a huge network of broadband internet satellites that orbit much closer to the Earth than a typical satellite, giving people on the ground a much stronger signal but covering a much narrower field of view. The design for L3Harris’ satellite is as yet unknown.
The Tracking Layer will, in turn, be part of a larger network of detection satellites called the Hypersonic and Ballistic Tracking Space Sensor (HBTSS), presently being developed by the SDA, Missile Defense Agency (MDA) and Defense Advanced Research Projects Agency (DARPA), which are described as having a “medium field of view.”
C4ISRNET reported in June the HBTSS project was chronically underfunded, and a March report by the Center for Strategic and International Studies think tank blasted the MDA and Congress for zigging and zagging on funding the project, saying “it is unclear that SDA plans to move out [that is, begin the effort] on hypersonic and ballistic missile tracking at the speed of relevance.”
Meanwhile, York Space Systems and Lockheed Martin are working on a related project, a much larger network of communications satellites that could include hundreds of pieces. The two firms received contracts in August to build a total of 20 satellites for this “Transport Layer” project. According to The Drive, this network might be intending to share information via laser communication instead of radio waves, which would be more reliable as well as immune to jamming or interception - key concerns of the Space Force.
This, in turn, could plug into other layers that track mobile launchers and other targets and could grow as large as 1,000 space-based devices.