Scientists Controlled Lightning With Lasers Aimed at the Sky In Breakthrough

For the first time in history, scientists have used lasers to harness lightning bolts and guide them into new trajectories, a breakthrough that could lead to enhanced protection from these dangerous strikes from the sky, reports a new study. 

The idea of diverting lightning with lasers dates back decades, but the newly reported experiment, which took place on Switzerland's Säntis Mountain in the summer of 2021, is the first to finally demonstrate this process in the field.

There’s nothing quite like the primal fear and awe evoked by the ominous flashes and booms of a thunderstorm, and for good reason. Though the odds of getting struck by lightning are very low, the consequences of these freak accidents are catastrophic: Thousands of people have been killed by lightning strikes, and countless more have suffered permanent injuries. 

The advent of metal lightning rods has reduced the risk of lightning-related casualties in many regions, but the protective range of these devices is limited to their immediate vicinity. Shooting laser pulses into the sky, in contrast, could theoretically extend a virtual shield around much larger areas, but attempts to pioneer this technology have fallen short—until now. 

Scientists led by Aurélien Houard, a researcher at ENSTA Paris at the Ecole Polytechnique, provide “the first field-result that experimentally demonstrates lightning guided by lasers” which represents “an important step forward in the development of a laser based lightning protection for airports, launchpads, or large infrastructures,” according to a study published on Monday in Nature Photonics.   

Houard and his colleagues successfully guided four “upward” lightning discharges, which are bolts that strike up from the ground, with laser pulses shot into the sky over Säntis Mountain. High-speed cameras recorded one of these intercepts, revealing that the lasers were able to guide a lightning strike for over 50 meters (164 feet). The findings suggest that laser-based lightning rods could potentially protect infrastructure over a half-mile radius, at elevations of several hundred meters.

“Lightning has fascinated and terrified humankind since time immemorial. Based on satellite data, the total lightning flash rate worldwide—including cloud-to-ground and cloud lightning—is estimated to be between 40 and 120 flashes per second , causing considerable damage and casualties,” the researchers said in the study.

“Here we present the first demonstration that laser-induced filaments—formed in the sky by short and intense laser pulses—can guide lightning discharges over considerable distances,” the team added. “We believe that this experimental breakthrough will lead to progress in lightning protection and lightning physics.”

The researchers achieved this milestone by installing a laser near a telecommunications tower on the mountain that is a hotspot for lightning strikes. During thunderstorms, the device shot laser pulses into the sky, a process that transforms particles and molecules in the air into plasma structures. 

Houard and his colleagues used a variety of techniques to show that this plasma can attract and guide lightning discharges, though the team was only able to redirect upward strikes, which are far more common at Säntis Mountain than the more familiar downward sky-to-ground strikes. To that end, the team hopes that future experiments will finetune this promising technology so that it can be implemented over critical infrastructure. 

“The results of the Säntis experimental campaign in the summer of 2021 provide circumstantial evidence that filaments formed by short and intense laser pulses can guide lightning discharges over considerable distances,” the team concluded in the study. “These preliminary results should be confirmed by additional campaigns with new configurations.”