Real-time detection of bright optical transients has an important role in modern astronomy, and many robotic telescopes have been built and operated for this purpose. However, since traditional narrow-angle telescopes cover only a very small portion of the sky at a given time, one can reasonably assume that some bright short-timescale transients may not be recorded by the available narrow-angle sky surveys.
In this study we applied a systematic all-sky automated search for bright short-timescale optical transients. The search used two panoramic all-sky cameras located in the northern and southern hemispheres, and could automatically alert on optical transients brighter than ~5.5th magnitude that lasted for 12 minutes or more.
After three years of operation, we recorded a seemingly ~5th magnitude optical transient detected for approximately 12 minutes by two CONCAM all-sky cameras located in Cerro Pachon -- Chile and La Palma -- Spain.
The data were also used to deduce upper limits to the frequency of short-timescale bright transient events.