June 8, 2023
Scientists used an enormous laser to deflect lightning

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Scientists had been in a position to create a digital lightning rod utilizing a big, highly effective laser atop a mountain in Switzerland, efficiently diverting the trail of lightning strikes.

Lightning deflection know-how hasn’t modified a lot since Ben Franklin invented the lightning rod in 1752. The Franklin rod, or a pointed metallic mast on prime of buildings and different constructions weak to lightning strikes, works by intercepting lightning and guiding the strikes safely to the bottom.

However the safety zone of Franklin rods is relative to their peak — a lightning rod with a peak of 10 meters (32.8 ft) protects an space with a 10-meter radius.

For the reason that peak of lightning rods isn’t infinite, broad ranges similar to airports, launchpads, energy stations, wind farms and nuclear energy crops pose a problem. Lightning causes as much as 24,000 deaths a yr and may trigger energy cuts, forest fires and injury infrastructure, in response to a research detailing the findings revealed Monday within the journal Nature Photonics.

Scientists determined to check if a laser beam pointed on the sky might act like one large digital and movable lightning rod. Earlier analysis has supported the concept that laser pulses might affect the trajectory of lightning strikes, however that work had solely been carried out inside a lab.

A laser the scale of a giant automobile was put in close to a telecommunications tower on the summit of Mount Säntis in northeastern Switzerland. Lightning strikes the tower about 100 occasions a yr.

Researchers activated the laser through the summer time of 2021 for greater than six hours throughout thunderstorm occasions between June and September. The Laser Lightning Rod, as it’s referred to as by members of the European consortium that developed it, was in a position to divert 4 lightning strikes.

Scientists used an enormous laser to deflect lightning

Excessive-speed cameras recorded the strikes, and different observations had been taken utilizing high-frequency electromagnetic waves created by the lightning in addition to the X-ray bursts related to the strikes.

“When very high-power laser pulses are emitted into the ambiance, filaments of very intense gentle kind contained in the beam,” research coauthor Jean-Pierre Wolf, professor of utilized physics on the College of Geneva, mentioned in a press release.

“These filaments ionise the nitrogen and oxygen molecules within the air, which then launch electrons which can be free to maneuver. This ionised air, referred to as plasma, turns into {an electrical} conductor.”

The laser’s channels of energized particles helped information the lightning strikes alongside the laser beam. The laser was able to firing as much as 1,000 pulses per second.

The Laser Lightning Rod weighs greater than 3 tons, is 1.5 meters (4.9 ft) large and eight meters (26.2 ft) lengthy.

The machine was examined at a peak of two,502 meters (8,208 ft) atop Mount Säntis and was designed by Munich, Germany-based TRUMPF scientific lasers to function even underneath tough climate situations, similar to fog that usually drifts across the mountain’s summit.

Lightning followed the laser beam for several dozen meters before reaching the tower (in red and white), according to the scientists.

“The principle problem was that it was a life-size marketing campaign. We needed to put together an surroundings by which we might set up and defend the laser,” mentioned research coauthor Pierre Walch, a doctoral pupil within the Laboratoire d’Optique Appliquée, a joint analysis unit of the Institut Polytechnique de Paris, the French Nationwide Middle for Scientific Analysis, École Polytechnique and ENSTA Paris, in a press release.

Every time storm exercise was forecast across the mountain through the experiment, the world was closed to air site visitors.

“The purpose was to see whether or not there was a distinction with or with out the laser,” mentioned lead research writer Aurélien Houard, analysis scientist on the Laboratoire d’Optique Appliquée, in a press release. “We in contrast the info collected when the laser filament was produced above the tower and when the tower was struck naturally by lightning.”

The analysis group labored for nearly a yr to research the info collected through the experiment.

“From the primary lightning occasion utilizing the laser, we discovered that the discharge might observe the beam for practically 60 meters (196 ft) earlier than reaching the tower,” Wolf mentioned, “that means that it elevated the radius of the safety floor from 120 meters (393 ft) to 180 meters (590 ft).”

Subsequent, the analysis group needs to extend the laser’s functionality by extending its attain and safety zone within the hopes that someday it could be used as a standard lightning rod various for broad areas.