In an exciting development earlier this year, the QZS6-HP1, the first of two space domain awareness (SDA) payloads, successfully launched from Tanegashima, Japan. This milestone was marked by the collection of its initial imaging data, often referred to as first light. The United States Space Force (USSF) sponsored this venture, with the MIT Lincoln Laboratory responsible for designing, constructing, and delivering these two payloads under the Quasi-Zenith Satellite System Hosted Payload (QZSS-HP) initiative. This collaborative effort embodies a steadfast commitment to strengthening space partnerships, ensuring alignment with both countries’ national space strategies while enhancing integrated deterrence and international security. Throughout this program, the Lincoln Laboratory collaborated closely with the USSF, Japan’s National Space Policy Secretariat, and Mitsubishi Electric Corp.
As satellite launches surge globally, driven by both government and commercial sector interests, the urgency to enhance space domain awareness in the increasingly crowded geosynchronous orbit (GEO) grows. Initiated in 2019, this international program pairs a U.S.-developed SDA sensor with Japan’s ongoing QZSS program, which is designed for users in Japan and enhances the capabilities of the U.S. Global Positioning System.
The USSF selected Lincoln Laboratory for this project due to its vast experience in developing SDA sensors, particularly showcased through the ORS-5/SensorSat satellite, launched in 2017. SensorSat is a small, cost-effective solution for tracking and detecting GEO satellites. In contrast to SensorSat, which relies on ground systems for data processing, the QZSS payloads perform the majority of their data processing on-orbit. This innovative approach significantly reduces downlinked data size by three orders of magnitude, making it ideal for missions with bandwidth limitations.
“The payload’s passive searching capabilities alleviate the workload of other SDA assets by providing continuous monitoring, contributing to a more resilient space architecture,” states Ashley Long, program manager for QZSS-HP at Lincoln Laboratory. These satellites will play a vital role in delivering near-real-time data to the U.S. Space Surveillance Network.
The second QZSS payload has been integrated onto Japan’s QZS-7 satellite, slated for launch in late 2025. Meanwhile, the Lincoln Laboratory team continues testing for QZS6-HP1 on-orbit.
Emily Clements, deputy program manager, emphasizes the significance of reaching the first-light milestone. “Achieving first light requires meticulous coordination among all system components, from the lab-fabricated sensor to the payload’s supporting subsystems and the data interfaces with ground systems in Japan and the U.S. This achievement signifies years of dedicated effort and international collaboration, paving the way for enhanced SDA monitoring of GEO,” she explains.
In the coming months, the Lincoln Laboratory team will further fine-tune sensor parameters based on the data collected in orbit to optimize performance. Their support will continue throughout the mission’s lifespan.
“Initially conceived as a demonstration mission to facilitate international cooperation, the QZSS-HP is poised to deliver substantial operational benefits for the United States,” adds Long. “The payload design has also been transferred to the government, enabling the construction and delivery of similar payloads, thereby extending the mission’s reach and impact.”
Photo credit & article inspired by: Massachusetts Institute of Technology
