The US Air Force's Constant Phoenix aircraft, known for detecting nuclear activity, was observed flying across several states, including Nebraska, South Dakota, and North Dakota, on Thursday. The flight sparked speculation online, especially as the US-Russia nuclear treaty approaches its expiration date. While officials have not disclosed the mission's purpose, such flights are often routine, involving crew training, equipment calibration, or background radiation monitoring, and are common in regions with strategic nuclear assets.

The Constant Phoenix has a long history of airborne nuclear detection, dating back to the late 1940s. Its missions have included tracking fallout from major incidents like the Chernobyl disaster and supporting international nuclear test ban treaties. The aircraft is equipped with specialized systems to collect and analyze atmospheric samples for radioactive debris, making it a key tool for monitoring nuclear activity worldwide. As the expiration of the New START Treaty looms, the recent flight has heightened public attention and concern.