The Rapid Action Electronic camera is a high-speed camera capable of recording a still image with an exposure time as brief as 10 nanoseconds. It was developed by Harold Edgerton in the 1940s and was first used to photograph the rapid changing matter in nuclear explosions within milliseconds of ignition. For a film-like sequence of high-speed photographs, arrays of up to 12 cameras were deployed, with each camera carefully timed to record a different time frame. Each camera was capable of recording only one exposure on a single sheet of film, so in order to create time-lapse sequences, banks of 4 to 10 cameras were set up to take photos in rapid succession.
A fuel assembly being extracted from the core of a boiling water reactor to be moved to a spent fuel pool and replaced.
Bringing a reactor from subcritical (offline) to supercritical is called a “pulse.” A reactor may produce around 4 megawats of power in its steady state mode, but during maximum pulse, the reactor can generate 35,000 megawatts. The pulse itself begins and ends in roughly 7 milliseconds. For that very short time, the reactor may produce 3 times the power of the United States’ largest reactor.
The pulse mode is also what operates in a nuclear weapon during the fraction of a second between releasing energy and exploding.
operation plumbbob: galileo
nevada test site
2 september 1957
yield 11 kt