Critical Assembly

Jim Sanborn's 2003 re-creation, Critical Assembly. The bottom hemisphere of the pusher, with pieces of the boron shell, tamper, pit, and urchin.

Critical Assembly is a sculpture by American artist Jim Sanborn which was displayed at the Corcoran Gallery of Art in Washington, D.C. in 2003. It included several elements, some actual and some re-created, which were part of the first project at Los Alamos laboratories to design the first atomic bomb.