Today we experienced a lightning storm, very mild, but suddenly there was like a static discharge in mid-air in the kitchen, 2 m in front of me, 1 m in front of the stove and microwave oven, about 1.8 m above the floor. The closest “object” was my wife’s head, about 0.5 m away. It was a light flash, the crackling sound of an electric discharge, and maybe 0.5 s later the thunder of a lightning strike was heard outside the kitchen window just behind my back. The house has a grounded copper wire all around the foundation that I installed myself. The grounding point is where the thunder was heard from. The discharge was not in the horizontal center of the loop, but closer to the grounding point. So far we haven’t found anything damaged by the lightning.
It doesn’t match the general description of a ball lightening, since they are longer lived and silent. This had all the features of an electrical discharge, although it happened in mid-air. So why did it happen? Apparently the electrical field got stronger than the dielectric breakdown voltage over some distance, maybe in the order of millimeters. For a distance of 5 mm, about 30 kV is needed. This is of course just speculation, but perhaps a strong current in a lightning outside the house, and or in the copper wire surrounding the house, created a strong magnetic field inside that, once the current ceased, gave rise to an induced electric field with a focal point in that spot in the air. A focal point? Well, perhaps it’s got to do with the limited speed by which an electrical field travels. Maybe the field is created as a wave from the electrical conductor in which the magnetic field is inducing the electricity, and the field from different parts collided in this spot in mid air to form a concentrated electrical field stronger than the breakdown voltage? Electricity is not my field, lightening is not my field, but it clearly appeared to be an electrostatic discharge in mid air, and that is the best hypothesis I can come up with.