Developed by Dr. Harold Edgerton in the 1940s,
the Rapatronic photographic technique allowed very early times in a nuclear explosion's fireball
growth to be recorded on film. The exposures were often as short as 10 nanoseconds, and
each Rapatronic camera would take exactly one photograph.
A bank of four to ten or more such cameras were arranged at tests to record different
moments of early fireball growth.
They provide technical information about the device's
disassembly. In some of the images shown below, accelerating bomb debris 'splashes' on a
relatively slower growing fireball surface, creating