Within a few days of detonating their first nuclear bomb, to the dismay of the Soviets, President Truman announced that they had the evidence to prove that within recent weeks an atomic explosion had occurred in the USSR. How the United States had obtained that knowledge was highly classified but we now know the story of the secret snoopers who sniffed the stratosphere and their spooky sorties!

The Castle Bravo test blast

The Tsar Bomba

American concerns over nuclear fallout

The WB-29

The RB-47H at the National Museum of the United States Air Force

Balloon debris

The RC-135

The long thin island of Novaya Zemlay

Images under Creative Commons licence with thanks to TravelingOtter, the US Department of Energy, Croquant, U.S. National Archives and Records Administration, Ruth AS, the USAF, the University of Texas, the SDASM Archives and NASA.