The United States has finalized the deployment of its current-generation space-based nuclear detection system, known as the Global Burst Detector. Officials confirmed the completion of the IIIA series, which has been in operation for over 60 years, and announced that development is underway for a more advanced successor scheduled to launch in 2027.
These specialized sensors, hosted on GPS satellites, provide continuous global monitoring for signs of nuclear detonations. The system is designed to identify and analyze key indicators from explosions, enhancing national security and global monitoring capabilities.
Key Takeaways
- The final sensor in the current IIIA series of the Global Burst Detector system is now operational after a May launch.
- The system is a joint effort between Sandia National Laboratories and Los Alamos National Laboratory, hosted on U.S. GPS satellites.
- It detects electromagnetic pulses, X-rays, and optical flashes to identify nuclear detonations in real time.
- A next-generation IIIF series is in development, featuring a new SIGHTS sensor capable of capturing over 10,000 frames per second.
- The first launch of the advanced IIIF series is planned for 2027.
A Continuous Watch From Orbit
For more than six decades, the United States has maintained a constant watch over the planet for nuclear explosions through its Global Burst Detection system. This network of sensors operates not on dedicated satellites but as payloads integrated into the U.S. Global Positioning System (GPS) constellation, ensuring comprehensive and cost-effective global coverage.
The system is a critical component of the broader U.S. Nuclear Detonation Detection System (NDS). This larger network includes a variety of satellites, ground stations, and sensors managed by the Department of Energy’s National Nuclear Security Administration (NNSA) and operated by the U.S. Space Force.
How the System Works
When a nuclear device is detonated, it releases a unique combination of energy signatures. The Global Burst Detector sensors are specifically designed to identify these signals, which include:
- Optical Flashes: The intense light produced by the explosion.
- X-rays: High-energy radiation emitted during the initial blast.
- Electromagnetic Pulses (EMP): A burst of electromagnetic energy that can disrupt electronic systems.
By detecting these phenomena, the system can almost instantly determine the time, location, and estimated yield of a detonation anywhere on or above the Earth's surface.
Milestone Reached with IIIA Series Completion
The final sensor package in the current block, designated the IIIA series, was launched from Cape Canaveral in May aboard a GPS satellite. Following the launch, the system underwent a period of calibration and on-orbit testing, which officials confirmed was successfully completed in June.
This deployment marks a significant achievement for the two national laboratories responsible for the technology's design and production: Sandia National Laboratories and Los Alamos National Laboratory. Leaders from both institutions highlighted the importance of the long-standing collaboration.
“The launch of the final IIIA series Global Burst Detector marks an important milestone in our efforts to enhance nuclear detection capabilities,” said Andrew Stuart, a manager at Sandia. He added that the collaboration “has been key to developing this advanced system, which will significantly contribute to our national security.”
Marc Kippen, program manager for space systems and science at Los Alamos, described the launch as “a testament to the decades of effort it takes to maintain uninterrupted national security space capability.”
The Next Generation: IIIF Series and SIGHTS Technology
With the IIIA series now fully deployed, engineers have shifted their focus to the next generation of detectors. Known as the IIIF series, these advanced sensors are scheduled to begin launching in 2027. Several of these new units have already been delivered to aerospace contractor Lockheed Martin for integration into the next block of GPS satellites.
A key innovation in the IIIF system is a new instrument called the Spectral Imaging Geolocation Hyper-Temporal Sensor, or SIGHTS. This optical sensor represents a major technological leap, stemming from basic research conducted at Sandia over a decade ago.
Unprecedented Speed and Precision
The SIGHTS sensor can capture images at an extremely high rate—tens of thousands of frames per second—at megapixel resolution. This capability allows for a much more detailed analysis of an optical flash, enabling operators to more quickly distinguish a genuine nuclear event from other phenomena and significantly reduce the chance of false alarms.
Built for a Harsh Environment
The IIIF detectors are engineered for longevity and reliability. According to Sandia, they will feature improved electronics, more robust materials, and advanced mission-assurance processes designed to ensure they can perform reliably for 15 years or more in the harsh environment of space.
To prepare them for this mission, the sensors undergo a battery of rigorous tests. The NNSA, which funds the program, requires that each unit survive simulated launch conditions and the space environment, including tests for shock, vibration, thermal vacuum, and exposure to prompt X-rays.
Over the next decade, Sandia and Los Alamos will continue to produce, deliver, and support the integration of additional IIIF systems, ensuring the continuity of this vital national security mission well into the future.
