Lightnings flash over Tirana
Mon, January 16, 2023
By Will Dunham
WASHINGTON (Reuters) - When Benjamin Franklin fashioned the first lightning rod in the 1750s following his famous experiment flying a kite with a key attached during a thunderstorm, the American inventor had no way of knowing this would remain the state of the art for centuries.
Scientists now are moving to improve on that 18th century innovation with 21st century technology - a system employing a high-powered laser that may revolutionize lightning protection. Researchers said on Monday they succeeded in using a laser aimed at the sky from atop Mount Santis in northeastern Switzerland to divert lightning strikes.
With further development, this Laser Lightning Rod could safeguard critical infrastructure including power stations, airports, wind farms and launchpads. Lightning inflicts billions of dollars in damage on buildings, communication systems, power lines and electrical equipment annually while also killing thousands of people.
The equipment was hauled to the mountaintop at an altitude of about 8,200 feet (2,500 meters), some parts using a gondola and others by helicopter, and was focused on the sky above a 400-foot-tall (124-meter-tall) transmission tower belonging to telecommunications provider Swisscom, one of Europe's structures most affected by lightning.
In experiments during two months in 2021, intense laser pulses - 1,000 times per second - were emitted to redirect lightning strikes. All four strikes while the system was active were successfully intercepted. In the first instance, the researchers used two high-speed cameras to record the redirection of the lightning's path by more than 160 feet (50 meters). Three others were documented with different data.
"We demonstrate for the first time that a laser can be used to guide natural lightning," said physicist Aurelien Houard of Ecole Polytechnique's Laboratory of Applied Optics in France, coordinator of the Laser Lightning Rod project and lead author of the research published in the journal Nature Photonics.
Lightning is a high-voltage electrical discharge between a cloud and the ground, within a cloud or between clouds.
"An intense laser can generate on its path long columns of plasmas in the atmosphere with electrons, ions and hot air molecules," Houard said, referring to positively charged particles called ions and negatively charged particles called electrons.
"We have shown here that these plasma columns can act as a guide for lightning," Houard added. "It is important because it is the first step toward a laser-based lightning protection that could virtually reach a height of hundreds of meters (yards) or a kilometer (0.6 mile) with sufficient laser energy."
The laser device is the size of a large car and weighs more than 3 tons. It uses lasers from German industrial machine manufacturing company Trumpf Group. With University of Geneva scientists also playing a key role, the experiments were conducted in collaboration with aerospace company ArianeGroup, a European joint venture between Airbus SE and Safran SA.
This concept, first proposed in the 1970s, has worked in laboratory conditions, but until now not in the field.
Lightning rods, dating back to Franklin's time, are metal rods atop buildings, connected to the ground with a wire, that conduct electric charges lightning strikes harmlessly into the ground. Their limitations include protecting only a small area.
Houard anticipated that 10 to 15 years more work would be needed before the Laser Lightning Rod can enter common use. One concern is avoiding interference with airplanes in flight. In fact, air traffic in the area was halted when the researchers used the laser.
"Indeed, there is a potential issue using the system with air traffic in the area because the laser could harm the eyes of the pilot if he crosses the laser beam and looks down," Houard said.
(Reporting by Will Dunham; Editing by Lisa Shumaker)
High-powered lasers can be used to steer lightning strikes
The technology could protect rocket launchpads and power plants.
Scientify/University of Geneva
Jon Fingas
·Reporter
Mon, January 16, 2023
Lightning rods have been used to safely guide strikes into the ground since Benjamin Franklin's day, but their short range (roughly the same radius as the height) and fixed-in-place design makes them ineffective for protecting large areas. The technology may finally be here to replace them in some situations. European researchers have successfully tested a system that uses terawatt-level laser pulses to steer lighting toward a 26-foot rod. It's not limited by its physical height, and can cover much wider areas — in this case, 590 feet — while penetrating clouds and fog.
The design ionizes nitrogen and oxygen molecules, releasing electrons and creating a plasma that conducts electricity. As the laser fires at a very quick 1,000 pulses per second, it's considerably more likely to intercept lightning as it forms. In the test, conducted between June and September 2021, lightning followed the beam for nearly 197 feet before hitting the rod.
Researchers have been exploring laser lightning guides for years. However, experiments have typically been limited to much shorter distances and relatively slow pulses that were more likely to miss lighting as it formed. Dr. Aurélien Houard, who helped lead the project, told the Wall Street Journal that this laser shot 100 times more pulses per second than in previous attempts.
It could be a long while before lasers are used beyond experiments. The University of Glasgow's Matteo Clerici, who didn't work on the project, noted to The Journal that the laser in the experiment costs about $2.17 billion dollars. The discoverers also plan to significantly extend the range, to the point where a 33-foot rod would have an effective coverage of 1,640 feet.
If the scientists succeed, the breakthrough could make lightning protection viable across large areas. This would be particularly useful for safeguarding rocket launchpads, where lightning strikes can force mission delays if they're too close to the flight path. They could also be helpful for protecting airports, power plants, forests and other sprawling locations where a strike could prove catastrophic
Giant Lasers Will Protect Us From Lightning Strikes
Maddie Bender
Mon, January 16, 2023
Maksim Isachenko / Getty
For all the technological innovation the modern industrial age has afforded us, protection against lightning is not on the list. To guard our homes and buildings from lightning strikes and subsequent fires, we still rely on the lightning rod, a technology invented by Founding Father Benjamin Franklin. Yes, really: Our best method at directing lightning still comes from the guy who tied a metal key to a kite and flew it during a thunderstorm.
Still, Franklin’s lightning rod—consisting of a conductive metal rod that directs lightning to strike the ground via a wire—works well for most situations. “The classical Franklin Rod is very efficient and relatively cheap,” Aurélien Houard, a physicist at École polytechnique in Palaiseau, France, told The Daily Beast in an email. “Its main limitation is related to its size, and to the fact that you cannot install lightning rods everywhere, while lightning strikes can fall almost everywhere.”
Lightning storms don’t just cause damage to buildings. Bolts can strike people, lead to hundreds of injuries and about 20 deaths each year in the U.S., and ignite devastating wildfires. Creating ways to protect more than just buildings from lightning’s damage—or better yet, devising a single method to attract lightning bolts and discharge them safely—would represent the biggest breakthrough in centuries for this area of study.
Improbably enough, scientists have managed to do just that. A team led by Houard and Swiss physicist Jean-Pierre Wolf have presented results that provide evidence that intense, short laser pulses can guide and potentially even trigger lightning to strike a single source. Their findings were published on Jan. 16 in the journal Nature Photonics.
TRUMPF/Martin Stollberg
In the 1960s, researchers discovered that lightning could be triggered and controlled by shooting small rockets attached to a conducting wire into the air during a storm. While clearly not a practical solution, the science behind this method gave the physicists an idea: Why not use a laser instead to emit a continuous conductive beam of energy and extend the range of a lightning rod?
“The laser creates a virtual extension of the metallic rod,” Houard explained, noting that a rod is typically only a few meters tall and can only protect as many meters far as it is tall. Lasers produce narrow beams of light, heating and detaching electrons from the air molecules in its path that can then conduct electricity. Lightning prefers to travel down a conductive path (which is why lightning rods work in the first place), so a giant laser beam will naturally guide it to the smaller metal rod underneath.
The physicists led an experiment during the summer of 2021 to test out their laser mountain on top of a telecommunications tower that itself was atop Mount Säntis, the highest mountain in a massif in northeastern Switzerland. After transporting the laser by truck and reassembling it at the peak of the mountain, the physicists operated the laser during thunderstorms between July and September 2021 for a total of 6 hours and 20 minutes.
By analyzing high-speed footage and a device that measures very-high-frequency activity characteristic of lightning strikes, the researchers found that the laser successfully guided four different lightning strikes. Shockingly, one of these strikes followed the path of the laser for more than 50 meters down to the metal rod, an impressively long distance.
Unlike previous unsuccessful attempts to construct a laser lightning rod, Houard said the group’s laser generated over 100 times more shots per second—since lightning can develop and discharge in milliseconds, this kind of precision likely played a crucial role in the team’s success. Additionally, the laser’s location upped the odds that lightning would strike in the general vicinity of the laser:
“In most of the places, lightning develops from the cloud to the ground, and it is impossible to predict precisely where it will go,” Houard said. “But on Mount Säntis, all the lightning flashes are hitting the tower, and this happens almost 100 times per year.”
Houard said that the researchers hope to repeat their experiment using different colored lasers and vary the amount of energy expended per pulse to collect more data and increase the lightning rod’s ambit. Then, they would like to test the laser in settings more similar to a real-world environment, not at the top of a mountain. Theoretically, with enough laser energy, one could generate temporary protection with a laser lightning rod hundreds of meters tall and protect very large and tall structures.
Though the analyzed results are only coming to light now, Wolf told CNN that the experiment’s success would have been apparent months earlier when experimentation ended in September 2021. “I think that at the end of September we will either open a bottle of champagne or a bottle of whiskey, if you see what I mean,” he said.
Maddie Bender
Mon, January 16, 2023
Maksim Isachenko / Getty
For all the technological innovation the modern industrial age has afforded us, protection against lightning is not on the list. To guard our homes and buildings from lightning strikes and subsequent fires, we still rely on the lightning rod, a technology invented by Founding Father Benjamin Franklin. Yes, really: Our best method at directing lightning still comes from the guy who tied a metal key to a kite and flew it during a thunderstorm.
Still, Franklin’s lightning rod—consisting of a conductive metal rod that directs lightning to strike the ground via a wire—works well for most situations. “The classical Franklin Rod is very efficient and relatively cheap,” Aurélien Houard, a physicist at École polytechnique in Palaiseau, France, told The Daily Beast in an email. “Its main limitation is related to its size, and to the fact that you cannot install lightning rods everywhere, while lightning strikes can fall almost everywhere.”
Lightning storms don’t just cause damage to buildings. Bolts can strike people, lead to hundreds of injuries and about 20 deaths each year in the U.S., and ignite devastating wildfires. Creating ways to protect more than just buildings from lightning’s damage—or better yet, devising a single method to attract lightning bolts and discharge them safely—would represent the biggest breakthrough in centuries for this area of study.
Improbably enough, scientists have managed to do just that. A team led by Houard and Swiss physicist Jean-Pierre Wolf have presented results that provide evidence that intense, short laser pulses can guide and potentially even trigger lightning to strike a single source. Their findings were published on Jan. 16 in the journal Nature Photonics.
TRUMPF/Martin Stollberg
In the 1960s, researchers discovered that lightning could be triggered and controlled by shooting small rockets attached to a conducting wire into the air during a storm. While clearly not a practical solution, the science behind this method gave the physicists an idea: Why not use a laser instead to emit a continuous conductive beam of energy and extend the range of a lightning rod?
“The laser creates a virtual extension of the metallic rod,” Houard explained, noting that a rod is typically only a few meters tall and can only protect as many meters far as it is tall. Lasers produce narrow beams of light, heating and detaching electrons from the air molecules in its path that can then conduct electricity. Lightning prefers to travel down a conductive path (which is why lightning rods work in the first place), so a giant laser beam will naturally guide it to the smaller metal rod underneath.
The physicists led an experiment during the summer of 2021 to test out their laser mountain on top of a telecommunications tower that itself was atop Mount Säntis, the highest mountain in a massif in northeastern Switzerland. After transporting the laser by truck and reassembling it at the peak of the mountain, the physicists operated the laser during thunderstorms between July and September 2021 for a total of 6 hours and 20 minutes.
By analyzing high-speed footage and a device that measures very-high-frequency activity characteristic of lightning strikes, the researchers found that the laser successfully guided four different lightning strikes. Shockingly, one of these strikes followed the path of the laser for more than 50 meters down to the metal rod, an impressively long distance.
Unlike previous unsuccessful attempts to construct a laser lightning rod, Houard said the group’s laser generated over 100 times more shots per second—since lightning can develop and discharge in milliseconds, this kind of precision likely played a crucial role in the team’s success. Additionally, the laser’s location upped the odds that lightning would strike in the general vicinity of the laser:
“In most of the places, lightning develops from the cloud to the ground, and it is impossible to predict precisely where it will go,” Houard said. “But on Mount Säntis, all the lightning flashes are hitting the tower, and this happens almost 100 times per year.”
Houard said that the researchers hope to repeat their experiment using different colored lasers and vary the amount of energy expended per pulse to collect more data and increase the lightning rod’s ambit. Then, they would like to test the laser in settings more similar to a real-world environment, not at the top of a mountain. Theoretically, with enough laser energy, one could generate temporary protection with a laser lightning rod hundreds of meters tall and protect very large and tall structures.
Though the analyzed results are only coming to light now, Wolf told CNN that the experiment’s success would have been apparent months earlier when experimentation ended in September 2021. “I think that at the end of September we will either open a bottle of champagne or a bottle of whiskey, if you see what I mean,” he said.
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