Saturday, February 04, 2023
Thursday, February 02, 2023
February 2, 2023 11:41 AM
Last October, CNET’s parent company, Red Ventures, held a cross-department meeting to discuss the AI writing software it had been building for months. The tool had been in testing internally ahead of public use on CNET, and Red Ventures’ early results revealed several potential issues.
The AI system was always faster than human writers at generating stories, the company found, but editing its work took much longer than editing a real staffer’s copy. The tool also had a tendency to write sentences that sounded plausible but were incorrect, and it was known to plagiarize language from the sources it was trained on.
Red Ventures executives laid out all of these issues at the meeting and then made a fateful decision: CNET began publishing AI-generated stories anyway.
“They were well aware of the fact that the AI plagiarized and hallucinated,” a person who attended the meeting recalls. (Artificial intelligence tools have a tendency to insert false information into responses, which are sometimes called “hallucinations.”) “One of the things they were focused on when they developed the program was reducing plagiarism. I suppose that didn’t work out so well.”
Of the 77 articles published on CNET using the AI tool since it launched, more than half have had corrections appended to them, some lengthy and substantial, after use of the tool was revealed by Futurism. CNET editor-in-chief Connie Guglielmo, EVP of content and audience Lindsey Turrentine, and Red Ventures vice president of content Lance Davis defended the tool in an internal meeting with staff in January but said the company would pause the use of the tool “for now.” In a follow-up blog post, Guglielmo said publishing using the AI software was on hold until CNET was confident it could “prevent both human and AI errors,” but she was clear that this wasn’t the end of AI tools in the newsroom.
“Expect CNET to continue exploring and testing how AI can be used to help our teams as they go about their work testing, researching and crafting the unbiased advice and fact-based reporting we’re known for,” Guglielmo wrote.
“Everyone at CNET is more afraid of Red Ventures than they are of AI.”
But the controversial use of an AI system to generate stories even in the face of known issues with plagiarism and accuracy is merely the most visible outcome of Red Ventures’ ownership of CNET. Under the ownership of Red Ventures, a private equity-backed marketing firm that’s bought up more than a dozen digital publishers since the mid-2010s, staff at the storied tech news outlet say they have been fighting to protect CNET’s editorial independence and rigor amid a push toward sponsored content and affiliate marketing by its new corporate owners. As one staffer told The Verge for a previous piece, “Everyone at CNET is more afraid of Red Ventures than they are of AI.”
Multiple former employees told The Verge of instances where CNET staff felt pressured to change stories and reviews due to Red Ventures’ business dealings with advertisers. The forceful pivot toward Red Ventures’ affiliate marketing-driven business model — which generates revenue when readers click links to sign up for credit cards or buy products — began clearly influencing editorial strategy, with former employees saying that revenue objectives have begun creeping into editorial conversations.
Reporters, including on-camera video hosts, have been asked to create sponsored content, making staff uncomfortable with the increasingly blurry lines between editorial and sales. One person told The Verge that they were made aware of Red Ventures’ business relationship with a company whose product they were covering and that they felt pressured to change a review to be more favorable.
“I understood a supervisor to imply in conversation that how I proceeded with my review could impact my chances of promotion in the future,” they say.
Red Ventures ignored an emailed list of questions from The Verge about its AI tool as well as CNET’s editorial independence and ethics, advertising, and staffing. The company instead offered to send a short statement about CNET’s editorial integrity but refused to provide it on the record attributable to anyone.
This apparent breakdown of the traditional barriers between editorial and advertising content is worlds away from CNET’s history, according to former staffers. Now more than 25 years old, the site has long been known for its thorough news coverage and comprehensive reviews program, which examines everything from laptops and phones to bookshelf speakers and home projectors.
“[The reason I came to CNET] was the opportunity to be able to tell the truth no matter what,” a former staffer says. To them, working at CNET was different from other journalism jobs, where journalists can be honest but may need to self-edit. “You get to tell the truth [at other jobs], but a lot of times, you’re not allowed to say things that you really feel.”
Are you a former or current CNET / Red Ventures employee? I’d love to hear from you. Contact me at email@example.com, and I’ll share my Signal.
But the CNET operated by Red Ventures is a very different place than the CNET it acquired in 2020. CNET, along with other Red Ventures-owned publications, is loading up on cheap SEO-driven articles to game Google’s search algorithm and fill search results with content designed to deliver affiliate links to readers. As a result, CNET’s independent journalism and the people who produce it — the thing that once made CNET valuable and rank highly in search to begin with — feel that they are being pushed out in favor of whatever and whomever else makes Red Ventures the most money, according to multiple former employees.
“When you’re [covering] products and not people, it’s really easy to be like, ‘This new Apple thing sucks.’ I just thought that was a refreshing change of pace to be able to say things as they are,” the former staffer says. “And that continued all the way until Red Ventures took over.”
After Red Ventures scooped up CNET for $500 million in 2020, CEO Ric Elias promised the outlet would be able to continue to be an independent publication known for its robust offering of reviews and in-the-weeds tech news coverage. CNET staff had nothing to worry about, Elias told The New York Times. There was a “nonnegotiable line” separating the journalism from the money, and CNET’s staff of tech journalists could call him on his personal cellphone if there were ever a problem.
“I told them, ‘There’s a red line,’ and they’re like, ‘OK, we’ll see,’” Elias said.
That skepticism now appears prescient. Former CNET staff say the guardrails that keep editorial content independent, like a divide between revenue teams and journalists, or a clear chain of command among leadership, were repeatedly breached after the Red Ventures acquisition. “Most of the time, [Guglielmo] seemed to just be relaying orders” from Red Ventures, a former staffer says. In turn, journalists were placed in difficult positions as they tried to fend off the encroaching influence of the business side.
Former CNET staffers describe being asked to work on ads for companies that the outlet covers, including Volvo and home security company Arlo and having to push back against such requests from executives at the company. Three people told The Verge that they believe resistance to Red Ventures initiatives caused various CNET staffers to lose their jobs, with one saying that the pressure to be a “yes man” was a “collective experience” for some teams.
Multiple former CNET staffers point to the demise of the CNET Smart Home as an example of Red Ventures’ overreach. The Smart Home — a four-bedroom, five-bathroom home in Louisville, Kentucky, that the outlet had purchased in 2015 to test and produce videos on home products like robot vacuums and thermostats — had become something of a brand in and of itself. Since Red Ventures’ takeover, Smart Home staff repeatedly refused to work on sponsored content, saying it went against the integrity of their work. Readers look to tech reviewers for honest, unbiased assessments of companies’ products and services, and working on content that is paid for by these same companies can cast doubt on a reviewer’s ability to be independent.
“It’s a culture that if you disagree with them, they’re going to get rid of you and replace you with a zealot.”
In 2022, a Red Ventures executive named Marc McCollum stopped by the Smart Home for a short walk-through. McCollum, according to his LinkedIn profile, led the acquisition of CNET Media Group. A former staffer says he played a key role in the transition, with a focus on increasing profits.
Shortly after McCollum’s visit, teams working out of the Smart Home learned that the company was planning on selling the house, and people working at the house believed their jobs would be at risk if the space were sold. But McCollum indicated that the company may be able to keep the house if it secured a lucrative advertising deal with GE Appliances, which had expressed interest in using the Smart Home for a commercial, multiple former employees say.
Hoping to avoid layoffs, some CNET staff pitched in on the GE Appliances deal in early talks and planning, and Red Ventures inked a deal. But CNET editorial staffers refused to shoot the ad itself, and contractors were ultimately used to work on the commercial, a former staffer says.
The GE Appliances shoot was ultimately moved from the Smart Home to an off-site location due to space limitations at the house, a GE Appliances spokesperson who would only identify themselves as “Whitney” told The Verge via email. GE Appliances was not aware of Red Ventures’ plans to sell the house, “Whitney” added.
But by the time the GE Appliances ad was released in September, many staff on the Smart Home team had already left the company. Seeing the “writing on the wall” — that the house would soon be put up for sale — some people were able to land new roles, a former staffer says; others were laid off that summer. The house was put up for sale shortly after the GE Appliances ad anyway, eventually selling in December for $1.275 million, according to Zillow.
“It’s a culture that if you disagree with them, they’re going to get rid of you and replace you with a zealot,” a former employee, who was laid off, says of Red Ventures. “Somebody that’s absolutely a true believer, [that] drinks the Kool-Aid.”
Former CNET staffers say their colleagues have also been pressured into appearing in ads for companies the outlet covers despite the murky ethics of using reporters in sponsored content. On-camera video hosts were uncomfortable with the idea of being in ads and pushed back against it, according to several former staffers. Using recognizable journalists for video content that’s paid for by advertisers can blur the lines and make it hard for viewers to tell what is and isn’t an ad.
In one recent video, titled “Moen Unveils Innovative Smart Sprinkler Product at CES,” a CNET host takes viewers through the company’s booth at January’s Consumer Electronics Show, interviewing company representatives and testing products. The video is an ad, but the host doesn’t say that, and neither the video description nor title included a disclosure until recently. The only disclaimer was a small pop-up that YouTube inserts when an uploader has indicated there’s a paid promotion in a video, though CNET doesn’t actually specify what in the video is promoted. Moen did not respond to multiple requests for comment about the nature of the sponsorship or its labeling. After The Verge asked Red Ventures about the ad, a disclosure was silently added to the video’s description.
One of the key priorities for Red Ventures seems to be the company’s focus on affiliate links, which pepper its portfolio of sites like The Points Guy, Bankrate, and CreditCards.com. Over time, a focus on affiliate revenue has crept into CNET’s editorial decisions, causing frustration among staff.
In one meeting after the Red Ventures acquisition, a former employee says editorial staff were shown how much the company earned through affiliate categories like home furnishings with the suggestion they keep it in mind when producing future content. CNET staffers were also told that a separate commerce team would begin writing video descriptions that included affiliate links, which many people worried would suggest on-camera hosts were endorsing specific products.
“Red Ventures’ big mantra is that they help people make life’s most important decisions,” a former staffer says. “And yet all of their influence has been to get people to make decisions that are going to be the most profitable to Red Ventures.”
CNET staff say that the proximity to revenue made it harder to maintain the editorial standards
“It’s very demoralizing. It’s actually soul-crushing. All you want to do is your job and you’re being told, ‘Don’t cover this,’ because the revenue potential is not there,” another former staff member says.
Advertising is what keeps most digital media companies afloat, and affiliate marketing is common across the industry. (The Verge earns a commission from affiliate links, as do other Vox Media-owned outlets, like The Strategist.) But in many newsrooms, there is a strict separation between the people dealing with advertisers and the people producing the news. At The Verge,for example, editorial staff never work on ads, and reviews writers don’t know how much parent company Vox Media earns through specific affiliate marketing links.
But under Red Ventures, former CNET staff say that the proximity to revenue made it harder and harder to maintain the editorial standards promised to audiences.
“I do believe that the journalists who are doing the work at CNET are extremely ethical. I think that they have a lot of integrity, I think they work really hard,” they say. “But I think that they are under a great deal of pressure to make money for Red Ventures. And that’s just never a good situation for journalists.”
Though the AI tool generating stories for CNET, Bankrate, and CreditCards.com was formally announced just weeks ago, Red Ventures’ “experiment” with enlisting artificial intelligence has been underway much longer. Like other publishers who’ve incorporated automated tools into their work, the Red Ventures proprietary AI software was sold to the newsroom as a way to more efficiently produce “the boring stuff” so writers could use their time instead to work on bigger projects. In actuality, enlisting artificial intelligence to write SEO bait accelerates the speed at which Red Ventures-owned websites can churn out search-optimized content loaded with affiliate links, cutting down the need for human writers — and the reporting they produce.
For Sarah Szczypinski, a former journalist on the CNET Money team who left the outlet in early 2022, the association with CNET in light of the AI-writing saga has been frustrating. Though Szczypinski quit many months before the AI-generated articles began appearing, people have started contacting her after the news broke, wondering if she, too, had used AI tools for her stories. Szczypinski maintains she wrote her stories on her own, without automation tools.
“The leadership team gave no thought to what these unilateral decisions would do to the people working there, especially the people who are journalists and need their readers to trust them,” Szczypinski told The Verge. “We still have lives to live and careers to forge. And we can’t do that with something as damaging as this hanging over our heads.”
In late January, Szczypinski contacted Red Ventures and CNET, asking to have her author page and bylines pulled. Her name has been scrubbed from dozens of articles, now replaced simply by “CNET Staff.”
Throughout the time Red Ventures has owned CNET, the outlet’s leadership has promised readers time and again that its journalism is as strong as ever. Even as Guglielmo, Turrentine, and Red Ventures executives dodged questions from readers, staff, and reporters about the AI system, they pointed to CNET’s track record built over decades as evidence of trustworthiness. Audiences trust CNET for tech news, reviews, and recommendations, they reasoned, so they can trust CNET for how to move forward with artificial intelligence.
But even the more public ways CNET has tried to elicit trust from its audience have been hollowed out by a relentless drive toward optimization and gaming the search algorithm at the expense of the very work that had made CNET valuable.
CNET’s public ethics policy has not been meaningfully updated in years — it still lists CBS as its parent company — but last year, the publication added nearly a dozen links detailing exactly how it tests and vets products to a hyper-specific degree, with separate posts for how CNET reviews everything from credit cards and TVs to vacuums and more. One way of looking at these posts is to provide readers — and potential customers — with as much detail as possible about CNET’s methodology.
But for Red Ventures, these articles are just more fodder to boost its bottom line: Google likes when publishers demonstrate “experience, expertise, authority, and trustworthiness,” and the search algorithm factors in articles like these when it ranks search results. Articles packed with words like “unbiased,” “credible,” and “thoroughly vetted” are great for Red Ventures’ SEO-heavy strategy.
After all, Google can’t tell if it’s true.
This story originally stated that CNET and Red Ventures had an advertising deal with GE. The deal was with GE Appliances, which GE sold to Haier in 2016. We regret the error.
Wednesday, February 01, 2023
Monday, January 30, 2023
Sunday, January 29, 2023
Wednesday, January 25, 2023
Recent Volcanic Activity on Jupiter’s Moon Io Is Confusing and Exciting Scientists - The New York Times
A New View of the Most Explosive Moon in the Solar System
"Recent strange activity around Jupiter’s volcanic moon, Io, confused and excited scientists.
Io, the third largest of Jupiter’s moons, is caught in a pressurized, explosive dance.
Orbiting near Ganymede and Europa, two of the other largest Jovian moons, and the planet itself, Io’s mineral composition is constantly pulled and pushed by gravity, creating frictional heat deep inside the moon. This makes it extremely volcanically active — there are hundreds of volcanoes and extensive networks of lava flows marking Io’s surface.
“It’s being squeezed like an anger ball,” said Jeff Morgenthaler, an astrophysicist at the Planetary Science Institute.
Despite a number of close-flying spacecrafts over the past few decades — including the Voyager 1 and Galileo missions — as well as constant observation from Earth, there are lasting mysteries about the kind of volcanic activity on Io and how the moon’s fiery energy interacts with Jupiter and other nearby bodies.
Last year, Dr. Morgenthaler, who studies gases Io emits and the cloud said gases create around Jupiter, picked up signs that a different kind of eruption — a more powerful or more persistent one — was occurring.
“It’s an exciting observation,” said Ashley Davies, a planetary scientist and volcanologist at NASA’s Jet Propulsion Laboratory who was not involved in Dr. Morgenthaler’s study. “It’s showing that Io is certainly one of the most energetic bodies in the solar system, and you have no idea how it’s going to appear when you turn your telescope on it.”
The observation could help to guide future study of Io, including preparations for NASA’s Juno space probe, which has been orbiting Jupiter since 2016 and is scheduled to fly only a couple hundred miles from the Jovian moon this December.
Because Io is far from the sun and has a very thin atmosphere, its surface, on average, sits at around minus 200 degrees Fahrenheit, and it is coated in a frosty layer of sulfuric compounds. Volcanic eruptions there, which come in many different forms and intensities, can reach temperatures up to 2,500 degrees Fahrenheit. When super hot meets super cold, molecules like sulfur dioxide and sodium can be shot into space. Some of the most explosive eruptions come from fissures in the surface and throw fountains of lava half a mile into space. The charged molecules create what is known as a “plasma torus” in Io’s wake: a doughnut-shaped cloud of ionized gas that collects in Jupiter’s magnetic field.
It is possible to look directly at Io’s volcanic hot spots with infrared telescopes. However, since 2017, Dr. Morgenthaler has taken a different approach, focusing on the moon’s plasma torus through the Planetary Science Institute’s Io Input/Output observatory (IoIO), in Arizona. Instead of using infrared light, Dr. Morgenthaler uses IoIO to block light from Jupiter and measure the gas around it.
Dr. Davies said that while infrared telescopes can tell us where volcanoes are erupting on Io and how powerful they may be, studying the plasma torus can tell us when an eruption is chemically rich — signaling that it may be more powerful, more persistent or just more peculiar. One eruption could push more ionized gas into the torus. Another could send out a lot of neutral gas. “It doesn’t happen every time, and it’s an interesting link,” Dr. Davies said.
Each year Dr. Morgenthaler has monitored volcanic activity through IoIO, he has noticed some kind of increased concentration, or brightening, of gases in the plasma torus. These changes correlate with volcanic outbursts, the intensities of which can be measured by the levels of sodium emitted from the moon. But, in September through December 2022, after a large volcanic outburst, he noticed that the torus contained much less sulfur dioxide than the size of the eruption would suggest. The torus wasn’t as bright as it should have been.
This could mean that the eruption had a different chemical composition from the others, or that different kinds of minerals had been disturbed. It would be like Mount St. Helens, a steep stratovolcano that can erupt explosively, sending dirt, rock and sodium into the atmosphere, erupting on Earth, rather than Mauna Loa, a gently-sloped shield volcano that erupts with liquid lava flows. Or it could mean that the torus was rapidly diffusing in response to the intense eruption.
More than anything, Dr. Morgenthaler said, it is a call for more research.
“I’m just raising the flag, and saying, ‘This has happened,’” Dr. Morgenthaler said after announcing the observation this month.
Studying the anomaly might draw out, in better detail, the different kinds of volcanoes on Io, as well as the interactions between the plasma torus and other massive moons around Jupiter. However, much more data will have to be gathered to put all the pieces together, including from other powerful telescopes on Earth, like the James Webb Space Telescope as well as from the Juno space probe.
For the moment, to study gases from Io, Dr. Morgenthaler said that his method, which is cheap and could be adapted by small research organizations and even some backyard astronomers, is often underutilized. But his work may open the door for similar and widespread research that could provide data to help understand the Jovian system.
Dr. Davies said that this kind of piecemeal research is integral to understanding Io. “You can think of it like looking at different parts of an elephant,” he said.
The fact that Dr. Morgenthaler’s most recent observation was made with largely accessible instruments opens the possibility of more studies, similar and different, in kind. “The more monitoring we can get, the better it will be,” said Dr. Davies."
Monday, January 23, 2023
Friday, January 20, 2023
Elon Musk admits at trial that he ignored pleas to stop tweeting
"Elon Musk will never stop posting, no matter who tells him to stop.
That was one of the takeaways from his brief testimony during his securities fraud trial, which took place in a San Francisco courthouse Friday. Lawyers for the plaintiffs peppered Musk with questions about his tweets as they work up to his infamous “funding secured” tweet from 2018 at the center of this case. Musk is being sued by a class of Tesla investors who claim his bumbling attempts to take Tesla private that year cost them millions of dollars.
Musk wasn’t asked about that tweet yet, though. He took the stand for a little over 30 minutes before the trial recessed until next Monday. But the plaintiff’s lawyers got in plenty of questions about his Twitter habits, most notably about all the people in his life who have begged him to quit the bird site.
Among the people who asked him to stop tweeting are Antonio Gracias, a former director on Tesla’s board, investors Ron Baron and Sam Teller, Musk’s former de facto chief of staff, and other close associates.
Musk got plenty of questions about his Twitter habits, most notably about all the people in his life who have begged him to quit
“I suppose I continued to tweet, yes,” Musk replied when asked if he ignored his advisors and investors.
(Worth noting: Musk tweeted a mere seven minutes before taking the stand and waited approximately 45 minutes after stepping down before sending his next tweet.)
The plaintiffs are working to portray Musk as a reckless tweeter who disregards good advice about the significant impact his public statements can have on his company’s stock price and shareholders. Early in his testimony, Musk was asked to describe the relationship between his tweets and Tesla’s retail investors.
“I care a great deal about retail investors,” Musk said. “There are our most loyal and steadfast investors.”
It’s easy to envision how this statement will come back to haunt him later in the trial, as plaintiffs’ lawyers are likely to remind him of the financial pain his tweets have caused these investors.
“I care a great deal about retail investors,” Musk said.
Musk was also asked to expound on one of his favorite subjects: short sellers. Tesla is one of the most shorted stocks on the market, and Musk has made no secret of his contempt for investors who bet against the success of his company.
“I believe short selling should be made illegal,” he said. “It is a means, in my opinion, for bad people on Wall Street to steal money from small investors. Not good.”
Most of the day’s testimony was devoted to Guhan Subramanian, a Harvard Business School professor and an expert witness for the plaintiffs, who described how unusual and unprecedented it was for Musk to try to tweet his way through Tesla’s managed buyout.
“What’s really different here is the communication of material non-public information about a managed buyout over Twitter,” Subramanian testified. “That’s just never been done before.”
A possible sign of Musk’s much-reported exhaustion: late in his testimony, he said there were “two main companies that I run and where I’m essentially the chief technologist and product person” — SpaceX and Tesla.
There was no mention of running a third company, Twitter."
Thursday, January 19, 2023
Wednesday, January 18, 2023
Microsoft to Lay Off 10,000 Workers as It Looks to Trim Costs
"The job cuts, which amount to less than 5 percent of the company’s work force, are its largest in roughly eight years.
Microsoft plans to lay off 10,000 workers, the company said Wednesday, as it looks to trim costs amid economic uncertainty and to refocus on strategic priorities, such as artificial intelligence.
The company employed about 221,000 workers as of the end of June, and the cuts amount to less than 5 percent of its global work force.
With the cuts, Microsoft becomes the latest tech giant to pull back after a frenzied few years of hiring, when the pandemic-fueled surge in online services and the expansion of cloud computing created fierce competition for tech talent.
“These are the kinds of hard choices we have made throughout our 47-year history to remain a consequential company in this industry that is unforgiving to anyone who doesn’t adapt to platform shifts,” Satya Nadella, Microsoft’s chief executive, said in a message to staff.
The layoffs, which will begin on Wednesday and continue through March, are the company’s largest in roughly eight years. Mr. Nadella cut about 25,000 jobs over the course of 2014 and 2015 as Microsoft abandoned its ill-fated acquisition of the mobile phone maker Nokia.
Like other tech companies, Microsoft expanded rapidly during the pandemic, hiring more than 75,000 people since 2019. Microsoft’s annual revenue grew 58 percent over three years, but rising interest rates and the prospect of a recession have tempered the company’s outlook. In the quarter that ended in October, it reported its slowest growth in five years and warned that more tepid results could follow.
Customers are seeking “to do more with less,” Mr. Nadella said. “We’re also seeing organizations in every industry and geography exercise caution as some parts of the world are in a recession and other parts are anticipating one.”
The changes, including severance and other restructuring expenses, will cost $1.2 billion, Mr. Nadella said. In a regulatory filing, Microsoft, which makes the Surface line of laptops and tablets, indicated some of the costs would come from making “changes to our hardware portfolio,” as well as consolidating office leases. Microsoft is scheduled to report its quarterly earnings on Tuesday.
Mr. Nadella said the company will continue to hire in strategic areas, and called advances in artificial intelligence “the next major wave of computing.”
The company has been pursuing several expensive bets, including potentially putting another $10 billion into its investment in OpenAI, which makes the explosively popular ChatGPT artificial intelligence system, and a $69 billion acquisition of the video game maker Activision that is facing challenges globally by antitrust regulators.
Other tech giants have also been reducing costs after several years of breakneck expansion. Amazon began what is expected to be a huge round of layoffs on Wednesday, as part of its plans to reduce its corporate work force by about 18,000 jobs.
The business software company Salesforce said this month that it planned to lay off 10 percent of its work force, or about 8,000 employees, and Meta, the parent company of Facebook, announced at the end of last year that it was cutting more than 11,000 jobs."
Monday, January 16, 2023
Scientists steer lightning bolts with lasers for the first time
"Demo during heavy storms at top of a Swiss mountain involved firing powerful laser pulses at thunderclouds
Scientists have steered lightning bolts with lasers for the first time in the field, according to a demonstration performed during heavy storms at the top of a Swiss mountain.
The feat, which involved firing powerful laser pulses at thunderclouds over several months last year, paves the way for laser-based lightning protection systems at airports, launchpads and tall buildings.
“Metal rods are used almost everywhere to protect from lightning, but the area they can protect is limited to a few metres or tens of metres,” said Aurélien Houard, a physicist at École Polytechnique in Palaiseau. “The hope is to extend that protection to a few hundred metres if we have enough energy in the laser.”
Lightning bolts are huge electrical discharges that typically spark over two to three miles. The charge carried in a bolt is so intense that it reaches 30,000C, about five times hotter than the surface of the sun. More than a billion bolts strike Earth each year, causing thousands of deaths, 10 times as many injuries, and damage that runs into tens of billions of dollars.
Traditional lightning rods date back to Benjamin Franklin who used to chase thunderstorms on horseback before his famous kite experiment in 1752. But in more recent times, scientists have looked for other ways to protect buildings and objects from damaging strikes.
Writing in the journal Nature Photonics, Houard and colleagues in Switzerland describe how they carted a powerful laser to the top of the Säntis mountain in north-eastern Switzerland and parked it near a 124m-high telecoms tower that is struck by lightning about 100 times a year.
The scientists waited for storms to gather and between July and September last year, fired rapid laser pulses at thunderclouds for a total of more than six hours. Instruments set up to record lightning strikes showed that the laser diverted the course of four upward lightning discharge over the course of the experiments.
Only one strike, on 21 July, happened in clear enough conditions for the researchers to film the path of the lightning from two directions using high speed cameras several kilometres away. The footage shows that the lightning bolt followed the laser path for about 50 metres, suggesting that the pulses helped steer the strike.
The laser diverts lightning bolts by creating an easier path for the electrical discharge to flow down. When laser pulses are fired into the sky, a change in the refractive index of the air makes them shrink and become so intense that they ionise air molecules around them. This leads to a long chain of what the researchers call filaments in the sky, where air molecules rapidly heat up and race away at supersonic speeds, leaving a channel of low density, ionised air. These channels, which last for milliseconds, are more electrically conductive than the surrounding air, and so form an easier path for the lightning to follow.
The laser is powerful enough to be a risk to the eyes of overflying pilots, and during the experiments air traffic was closed over the test site. But the scientists believe the technology could still be useful, as launchpads and airports often have designated areas where no-fly restrictions apply. “It’s important to consider this aspect of safety,” said Houard.
More powerful lasers that operate at different wavelengths could guide lightning over longer distances, he added, and even trigger lightning before it becomes a threat. “You avoid it going somewhere else where you cannot control it,” Houard said.
“The cost of the laser system is very high compared with that of a simple rod,” said Professor Manu Haddad, director of the Morgan-Botti Lightning Laboratory at Cardiff University. “However, lasers could be a more reliable way to direct the lightning discharge, and this may be important for the lightning protection of critical ground installations and equipment.”