ARGONNE NATIONAL LABORATORY / US DEPARTMENT OF ENERGY / SCIENCE PHOTO LIBRARY ARGONNE NATIONAL LABORATORY / US DEPARTMENT OF ENERGY / SCIENCE PHOTO LIBRARY
First nuclear reactor test design. This uranium-graphite lattice pile is one of at least 29 similar structures that were built during testing in the development of the world's first nuclear reactor, the Chicago Pile-1 (CP-1) at the University of Chicago, Chicago, Illinois, USA. This type of pile was called a sigma pile. Thirty exponential piles resembling this one were built to help scientists as they developed CP-1. These exponential piles were the equivalent of criticality experiments or preliminary pile assemblies. The world's first self-sustaining nuclear reaction was initiated in the CP-1 reactor on 2 December 1942. This work led to the production of the fuel for the first atom bombs, as part of the Manhattan Project.
Model release not required. Property release not required.