Benjamin Franklin proposed his famous kite experiment in 1752 to draw electricity from the sky into a Leyden jar. Today, we can perform a safer version of this experiment in the lab with a tiny water droplet instead of a kite. With the help of a high-voltage power supply to generate the necessary voltage and a high-speed camera to capture the moment when the lightning hits the droplet, we obtained this image. Our sub-millimeter “kite-droplet” resting on a superhydrophobic surface responds to the applied electric field by deforming its upper tip into a conical shape that concentrates the electric field and initiates the lightning. Not only can we replicate the kite’s experiment at a smaller scale in the lab, but we can also control its parameters easier. This is important for us to understand a phenomenon before studying its manifestation in bigger and more complex systems. From shedding condensate droplets from the surface of heat exchangers to possibly reducing the risk of thunderstorm accidents, our research sees many applications worth consideration. But for now, “when thunder roars, go indoors!”
