US military ends long-running program to spot nuclear missile launches
Summary
Ars Technica reports that the Defense Support Program (DSP) constellation, a cornerstone of space-based early warning since the 1970s, has officially retired. The final two DSP satellites performed disposal maneuvers, as the United States transitions to newer infrared systems (SBIRS and Next-Generation OPIR) with first launches anticipated within 12 months. The article frames this as a major modernization step in space-based missile warning and defense policy.