Laser-powered lightning rods pull electricity out of the sky

Laser powered lightning rods pull electricity out of the sky

Lightning researchers at the Hebrew University of Jerusalem in Israel have developed a laser system that could be used to channel lightning bolts away from easily-damaged targets.

Normally, when a powerful laser is shot through the air, it leaves a trail of plasma in its wake. We don't normally see that plasma, because it only lasts a few nanoseconds, and it's less then a hundredth of a hair-width wide. After that, the trail disappears.

A Factor of Ten

Because the plasma trail conducts electricity, that means it can serve as a channel that lightning can move along. But a few nanoseconds isn't long enough for that process to happen.

By firing a second laser along that trail, however, the plasma is kept hot and its duration can be extended by more than a factor of ten. That's now long enough for it to be used to redirect a lightning strike.

"The beauty is that you can extend it for pretty much as long as you want, as long as you have the proper optical set-up and a laser beam with enough power," said Jenya Papeer, who's planning to present the work at an optics conference in October.

Image credit: Washburnbr // CC BY 2.0