Sophia McCollum, USSF Space Systems Command; Brandon Hammond, USSF Space Systems Command; Brynn Feighery, USSF Space Systems Command
Keywords: Space Domain Awareness, Hosted Payload, International Partnership
Abstract:
In December 2020, the United States Space Force (USSF), via General Raymond, and Japan’s National Space Policy Secretariat (NSPS) agreed that Japan would host two (2) USSF payloads on two (2) Japanese satellites, QZS-6 and QZS-7, the first ever international partnership between the United States (US) and Japan. QZSS is Japan’s sovereign Position, Navigation, and Timing (PNT) constellation of satellites. The two (2) US Department of Defense payloads are electro-optical volume search sensors that contribute to Space Domain Awareness (SDA) for the USSF. QZSS-HP enables the US and Japan to extend the alliance and our integrated deterrence posture into the space domain. In November 2023, SDA Doctrine for US Space Forces pivoted from “tasked-track” to “search-based” methodology. QZSS-HP is meant to start this pivot to a “search-based” methodology utilizing its wide field of view sensor to tip and queue other exquisite sensors already on-orbit. Additionally, it begins to close the “noon gap” issue that ground sensors and other space-based SDA sensors are plagued with. These sensors are designed to scan large volumes of the Geosynchronous Belt with an automatic scan pattern at a regularly defined cadence and will provide operationally relevant data in near real time. If scaled and proliferated, the envisioned sensor layer would require six (6) sensor pairs (twelve (12) payloads total). Deploying in sensor pairs (i.e. East mounted and West mounted payloads facing across from one another), the payloads can work synergistically to extend operations into late morning and from early afternoon, narrowing or eliminating the noon gap. The program successfully launched QZS-6 and HP 1 on 2 February 2025 and is awaiting Japanese on-orbit checkout and verification to complete before powering on the payload and beginning on-orbit developmental testing. QZS-7 and HP 2 are undergoing Assembly, Integration, and Test and are on track for a December 2025 launch. Although these are prototype sensors, the data will be used operationally after undergoing data verification by Space Operations Command/S9I.
Date of Conference: September 16-19, 2025
Track: Space Domain Awareness