In a first for science, researchers managed to direct lightning into the sky with the help of a powerful laser shot. The powerful laser deflected lightning approximately 60 meters before it hit the lightning rod, greatly improving the rod’s function.
The results, published in January, suggest lasers could one day be used to protect against dangerous storms that kill an average of 43 people in the US each year and cost US homeowners nearly $1 billion in insurance payments in 2022.
In addition, the trajectory of the laser radiation passing through the clear sky is also superimposed due to the formation of the second harmonic.
Lasers as lightning rods
Aurelien Ward, a researcher and project coordinator at the Optical Applications Laboratory of EPFL University in Switzerland, said in his blog on the French website Polytechnique Insights that the idea of using laser lightning rods arose in the early 1970s.
The principle is simple: Laser beams, if they are powerful enough, can heat air so much that they force molecules to release electrons. This creates a channel full of charged electrons along the laser beam, and all of these electrons attract lightning seeking the path of least resistance between the clouds and the ground.
The problem is that the lifespan of this channel is very short and the laser beams flicker. Although scientists have succeeded in deflecting lightning in the laboratory, they have never been able to do so in real conditions. To ensure that the channel remains open long enough to deflect lightning during a storm, scientists have developed a laser that can emit powerful pulses 1,000 times per second.
This was a joint effort between the University of Geneva (UNIGE) and EPFL in Switzerland, the Ecole Polytechnique in France, and the scientific laser company TRUMPF in Germany. Howard told The Wall Street Journal that their laser pulses 100 times faster than previous lasers, which means the laser is “100 times more likely to catch lightning.”
Testing laser on top of Swiss mountain
To test the new equipment, scientists took their three-ton laser to the top of the 8,000-foot Mount Sentis in Switzerland. The advantage of this place is the 400-meter communication tower, which is guaranteed to be struck by lightning at least 100 times a year.
The laser was turned on when the weather forecast predicted a storm.
Finally, scientists were able to record the natural lightning that followed the laser beam before it hit the tower.
“Of course, we had to analyze much more data from now on,” Jean-Pierre Wolff, professor of applied physics at UNIGE, said in a video accompanying the results in French.
“But this picture spoke a thousand words, there was no doubt about that. “When I saw this photo, I realized it was there,” he said.
Flood prevention equipment needs updating
This discovery raises hopes that lasers may one day offer much-needed new capabilities for lightning protection.
Lightning rods, invented by Benjamin Franklin, remain the best lightning protection method we have, according to a press release accompanying the findings. The problem is that their protection only extends to the height of the shaft. According to the press release, this means that a 10-foot pole will protect anyone within 10 feet of the pole, but nothing more than that.
On the other hand, the laser can reach high above the clouds.
“We found that the discharge could follow the beam for almost 60 meters (196 feet) before reaching the tower,” Wolff said, according to CNN.
This meant that the laser “increased the radius of the protective surface from 120 meters (393 feet) to 180 meters (590 feet).” The next step will be to try to develop a laser that can go even higher in the sky. Source
Source: Port Altele
