lightning mapper

Noun

 * 1)  A system that displays a map of the position of recorded or real-time lightning discharges relative to the user or other objects.
 * 2)  The component of such a system that gathers the required data, comprising an interconnected network of electric field change sensors that measure the time of arrival of electric field pulses from the strokes in a lightning flash. Two-dimensional maps require three such sensors, and three-dimensional maps require four.