Research Shows Laser-Guided Lightning Is Possible

It would be quite a stretch to say they’ve harnessed lightning, but researchers in Switzerland did succeed where many others have failed: They’ve shown that a laser beam can be used to steer or divert lightning. Per the Guardian, it happened high in the Swiss Alps last summer, when a team led by French scientist Aurelien Houard mounted a car-sized device to a telecommunications tower atop Mount Santis and fired laser pulses into approaching thunderclouds. The research was published this week in the journal Nature Photonics.

Over the course of two months, instruments used to record lighting showed that the device diverted four strikes. According to Nature, the laser’s rapidity was the key to success: it fires about 1,000 high-energy pulses per second, far more than anything used in past experiments. In theory, the laser beam alters the surrounding air by forcing molecules to absorb and emit energy very quickly, thereby reducing the density of the air and creating a favorable conductive pathway, "like drilling a hole through the air with the laser," as Houard puts it. Only one strike occurred in conditions suitable to be captured by high-speed cameras, which reportedly showed a bolt following the laser’s path for about 50 yards.

The tower where the experiment took place gets struck about 100 times annually, accounting for a fraction of the billion lightning strikes around the globe each year that kill thousands and cause billions in property damage. Thanks to Ben Franklin, lightning rods have long been used to protect buildings and other sensitive areas, but lasers could cast a far wider safety net. Per the Washington Post, Houard envisions the technology being applied at airports or launchpads for rockets. "It’s quite expensive. It costs about 1 million euros. You would not use it for any small protection," Houard said. One lightning expert not associated with the research told the Post it’s "a big step forward," but "we’re a long ways away from having the technology to keep everybody safe from lightning." (More lightning stories.)