Coronal Discharge
Coronal Discharge : (1) (Techn) A phenomenon used to detect voids in otherwise homogeneous dielectric material. An electrical potential ionizes materials within a void causing a burst of current that is easily detected. (2) (Meteor) A brush-like, luminous discharge of electricity into the atmosphere from charged objects, such as from ship's masts and airplane propellers and wing tips during electrical storms. Also called: St. Eimo's Fire