Ryan van Herel and Stewart Hardie/ISNS/2011 AIP

ScienceShot: How to Tame Lightning

Who at school didn't like to play with a Van de Graaff generator? Wind it up, put a finger close to the metal shell and—zap!—a spark jolts across the gap. Now imagine the length of that electrical discharge isn't a few millimeters, but 60 meters. That's the accomplishment of a team of electrical engineers, which has developed a new way to create electrical discharges, or "arcs." As they will report in an upcoming issue of the Journal of Applied Physics, the researchers hooked up a thin, 60-meter-long copper wire to the terminals of a 270-kilovolt electrical supply. When they turned it on, the wire exploded into several short sections, forming beads of plasma, or conductive gas. These plasma beads grew rapidly until they formed a channel, allowing the discharge of a striking white arc. The researchers believe this "exploding wire" method, which needs less than 5% of the electric field required for an arc without an initial wire, could be used to make record-breaking arcs, hundreds of meters long. One application might be to capture lightning from thunderclouds, to save it from striking manmade objects on the ground.

See more ScienceShots.

Follow News from Science

A 3D plot from a model of the Ebola risk faced at different West African regions over time.
Dancing sneakers on pavement
siderailarticle x promo