Lightning strikes 40-120 times a second worldwide. Lightning strikes kill more than 4,000 people and cause billions of dollars in damage every year.
Virtual lightning rod with laser
The measure to protect structures against lightning has long been a modest lightning rod. This column was created in 1749 by the American scholar Benjamin Franklin.
A team of scientists from six research institutions worked for several years to develop the same idea. They found a way to replace simple metal columns with more sophisticated and precise lasers.
In a study published in the scientific journal Nature Photonicsscientists say they used a laser beam – fired from the top of a Swiss mountain – to guide a lightning bolt more than 50 meters away.
Professor Aurelien Houard, a physicist at the laboratory of applied optics at the ENSTA Paris Institute of Science & Technology and lead author of the study, said: “We wanted to present the first evidence that lasers have can affect lightning, and the simplest way is to guide it.”
But for future applications, “it would be even better if we could actively trigger the lightning,” Mr Houard told the News Agency. AFP.
How to catch lightning?
Lightning is an electrostatic discharge that builds up in storm clouds or between clouds and the ground.
The laser beam creates plasma, in which charged ions and electrons heat the air.
Mr Houard said the air would become “partially conductive and that’s the path of lightning”.
A powerful laser aimed at the sky can create a virtual lightning rod and redirect the lightning strike.
This discovery could pave the way for better lightning protection methods for critical infrastructure, such as power plants, airports and rocket launchers.
Push the lightning bolt away from the building 50 m
For the latest experiment, the scientists dragged a car-sized laser device – which can emit thousands of pulses of light per second – to the top of the 2,500-meter-high Mount Santis in northeastern Switzerland.
This peak is home to a communication tower that is struck by lightning about 100 times a year.
During a storm in the summer of 2021, scientists were able to image their laser beam redirecting a lightning bolt about 50 meters away.
Three other tests also yielded the same results through interferometric measurements.
However, scientists have only redirected lightning away from the contact range of a few tens of meters.
To extend the protection of structures to several hundred meters, a more powerful laser is required. This is something scientists think they haven’t mastered yet.