The United States military is actively developing new technologies to monitor spacecraft and other objects operating in the increasingly contested space between Earth and the Moon. This push for improved surveillance comes as both commercial and governmental activity in this region—known as cislunar space—intensifies, particularly between the US and China.
The Need for Cislunar Tracking
Current tracking systems are primarily designed for satellites in low Earth orbit (LEO) and geosynchronous orbit (GEO). However, the ability to detect and track objects much further away—specifically near the Moon—remains limited. The Defense Advanced Research Projects Agency (DARPA) has issued a contract solicitation for advanced optical signal processing to address this gap. The goal is continuous, space-based detection of objects at distances exceeding 140,000 miles (225,000 kilometers).
DARPA’s Track at Big Distances (TBD2) Program
The TBD2 program aims to improve early warning capabilities for defense and civilian agencies. While the specific “potential threats” are not explicitly stated, the timing coincides with heightened geopolitical competition in the race to return to the Moon. The program seeks software algorithms paired with commercially available optical sensors onboard spacecraft. These sensors would need to process signals onboard and track faint objects within hours.
Strategic Positioning for Surveillance
DARPA’s solicitation calls for two payload designs: one for placement at Lagrange Point 1 (L1), a gravitationally stable location between Earth and the Sun, and another for “beyond GEO/cislunar orbits.” Additional focus is on Earth-Moon Lagrange points (EMLs), which could allow monitoring of the “Earth-Moon corridor” and detection of objects as small as 10-20 centimeters at distances of 125,000-250,000 miles.
Broader Military Efforts
The TBD2 program is not the only US military initiative focused on cislunar surveillance. The Space Systems Command (SSC) and the Air Force Research Laboratory (AFRL) are testing new propulsion technologies to develop spacecraft capable of “persistent situational awareness” in this region.
Implications of the New Space Race
The push for better lunar tracking reflects a growing concern that the US is falling behind China in the renewed space race. Former NASA Administrator Jim Bridenstine has warned that unless significant changes occur, China is likely to reach the Moon first. The nation that establishes a dominant presence on the Moon will dictate access to lunar resources, control international partnerships, and potentially reshape the global economic and security landscape.
“Whichever nation reaches the moon first…will be able to dictate the rules for accessing and using lunar resources,” warned Mike Gold, president of Redwire.
The US military’s pursuit of enhanced lunar surveillance capabilities underscores the strategic importance of cislunar space in the 21st century. This push for dominance reflects a broader competition for control over emerging technologies and the future of space exploration
