Traditionally astrophysics has concerned itself with minimum time-scales measured in hours rather than seconds. This was understandable as the available recording media were slow; . chart recorders and photographic plates. In the 1950s, 60s and 70s wavebands away from the optical were developed; from ground based radio studies to space and balloon borne high energy work. In contrast to optical wavelengths instrumentation in these (high and low energy) regimes was capable of time resolutions of less than a second
