Using lasers to divert potentially damaging lightning strikes may sound like the stuff of science fiction, but some clever folks across the pond have apparently achieved such a feat.
The technology, if fully developed, would be more effective than the long-used Franklin rod and therefore could become a valuable protection measure for sites like power stations, airports, and launchpads.
A research team led by physicist Aurélien Houard of École Polytechnique in Palaiseau, France, spent time experimenting with lasers on a Swiss mountain with a telecommunications tower, which, perhaps not surprisingly, sees a fair bit of lightning coming its way.
The research involved aiming powerful pulses from a high-repetition-rate terawatt laser toward thunderclouds close to the mountain. High-speed cameras were used to see what happened, with footage from a lightning strike showing the bolt following the laser for about 50 meters.
According to the team, firing the laser pulse ionizes the air molecules to produce a highly conductive channel of plasma for the electrical discharge to flow along.
“Metal [Franklin] rods are used almost everywhere to protect from lightning, but the area they can protect is limited to a few meters or tens of meters,” Houard said in comments reported by the Guardian. “The hope is to extend that protection to a few hundred meters if we have enough energy in the laser.”
The team said that although a fair amount of research has already been done on the subject over the last 20 years, “this is the first field result that experimentally demonstrates lightning guided by lasers.”
It added: “This work paves the way for new atmospheric applications of ultrashort lasers and represents an important step forward in the development of a laser-based lightning protection for airports, launchpads, or large infrastructures.”
There are several things to consider, however. For example, the powerful laser could impact the eyesight of nearby pilots, so the direction of the lasers would have to be carefully planned. And while the technology would protect an area greater than that offered by a Franklin rod, implementing the high-tech system would cost more money.
If you’re keen to dive into the complexities of the research, head over to Nature, which published the team’s work this week.
