Latest news with #VictorPasko
Yahoo
6 days ago
- Science
- Yahoo
Lightning Might Be Irradiating Our World Without Ever Showing Its Face. Here's How.
Here's what you'll learn when you read this story: Scientists have long understood why lightning forms, but the atomic processes at the core of the phenomenon have remained largely a mystery—especially the strange mechanics behind terrestrial gamma-ray flashes (TGFs). A new study combines ground-based observation with mathematical models to detail the high-energy photons and X-rays responsible for TGFs. This gives scientists one of the clearest pictures yet of exactly how lightning forms within a thundercloud. When it comes to lightning, it only takes learning a few facts to learn that these brief moments of raw atmospheric power have precisely zero chill. For one, there are roughly 8.6 million lightning strikes on Earth per day, and those terrifying bolts can temporarily superheat the surrounding air to a toasty 50,000 degrees Fahrenheit (a.k.a. five times hotter than the surface of the Sun). Incredibly, lightning can even briefly produce gamma-rays, which are typically spewed from things like supernovae or black hole jets. In other words: when lightning goes, it goes hard. While scientists have a pretty firm grasp on why lightning forms in cumulonimbus clouds, they don't exactly understand the atomic phenomena underpinning the phenomenon. Why, exactly, does lightning produce electromagnetic energy that rivals some of the most intense celestial ongoings in the universe? Now, in a new study from Pennsylvania State University, scientists used mathematical models combined with ground observations to discern the exact atomic workings that create lightning bolts in the first place. The results of the study were published in the journal JGR Atmospheres. 'By simulating conditions with our model that replicated the conditions observed in the field, we offered a complete explanation for the X-rays and radio emissions that are present within thunderclouds,' Victor Pasko, lead author of the study from Penn State, said in a press statement. 'We demonstrated how electrons, accelerated by strong electric fields in thunderclouds, produce X-rays as they collide with air molecules like nitrogen and oxygen, and create an avalanche of electrons that produce high-energy photons that initiate lightning.' Two years ago, Pasko and his team published a Photoelectric Feedback Discharge model, which simulates conditions ripe for lightning activity. And earlier this year, an unrelated study from the University of Osaka observed and detailed the extremely brief moments of terrestrial gamma-ray flashes, or TGFs, using a multi-sensor set-up. They found that TGFs appeared 31 microseconds before connection of the discharge path with the full burst lasting another 20 microseconds after the two discharge paths—one from the ground and one from the air—meet. This new study wanted to understand why these TGFs were often produced without flashes of light or radio wave bursts. Driven by the photoelectric effect, which explains how materials or atoms release electrons when struck by light, the variable strength of the runaway chain reaction that occurs in lightning bolts can precisely produce these initially unintuitive conditions. 'In our modeling, the high-energy X-rays produced by relativistic electron avalanches generate new seed electrons driven by the photoelectric effect in air, rapidly amplifying these avalanches,' Pasko said in a press statement. 'In addition to being produced in very compact volumes, this runaway chain reaction can occur with highly variable strength, often leading to detectable levels of X-rays, while accompanied by very weak optical and radio emissions. This explains why these gamma-ray flashes can emerge from source regions that appear optically dim and radio silent.' Lightning has long been an atmospheric phenomenon on Earth, and one leading theory even speculates that it might have helped kickstart life on the planet. Now, a couple billion years later, that life is finally revealing its high-energy secrets. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life? Solve the daily Crossword
Yahoo
31-07-2025
- Science
- Yahoo
What happens right before lightning strikes? Scientists have solved the mystery
Scientists say they've finally solved the mystery behind what happens just before lightning strikes. While famous inventor and U.S. Founding Father Benjamin Franklin discovered the connection between lightning and electricity back in 1752, experts still had not fully understood the journey from the cloud to the ground more than 270 years later. 'Our findings provide the first precise, quantitative explanation for how lightning initiates in nature," Victor Pasko, a professor of electrical engineering in the Penn State School of Electrical Engineering and Computer Science, said in a statement announcing the findings. "It connects the dots between X-rays, electric fields and the physics of electron avalanches." So, what's the deal with the atmospheric processes that trigger the giant, explosive sparks of electricity that can heat the air to a temperature five times hotter than the surface of the sun? According to Pasko and his team, the powerful chain reaction works similarly to an invisible pinball machine. Inside the storm clouds, strong electric fields speed up electrons that crash into molecules, such as nitrogen and oxygen. The reactions produce electromagnetic radiation commonly known as X-rays, as well as even more electrons and high-energy photons. Photons are the fundamental particles that make up light. After this, the lightning bolts are born. Atmospheric scientists knew how charged particles react within clouds. Protons rise and electrons descend toward the ground, resulting in a positive electric charge building on the ground. When that positive charge 'reaches out' to the approaching negative charge and the channels connect, the electrical transfer is what we see as lightning, according to the National Oceanic and Atmospheric Administration. To reach these new conclusions, the international authors used mathematical modeling, simulating the physical conditions in which a lightning bolt is likely to originate. 'We explained how photoelectric events occur, what conditions need to be in thunderclouds to initiate the cascade of electrons, and what is causing the wide variety of radio signals that we observe in clouds all prior to a lightning strike,' Zaid Pervez, a doctoral student in electrical engineering, said. 'To confirm our explanation on lightning initiation, I compared our results to previous modeling, observation studies and my own work on a type of lightning called compact intercloud discharges, which usually occur in small, localized regions in thunderclouds.' They also sought to explain observations of what is known as 'dark lightning' or a terrestrial gamma-ray flash. The invisible X-ray bursts are comprised of the flashes, which are produced in our atmosphere. They're often produced without flashes of light and radio bursts, which are familiar hallmarks of lightning during stormy weather. The researchers wanted to know why. 'In our modeling, the high-energy X-rays produced by relativistic electron avalanches generate new seed electrons driven by the photoelectric effect in air, rapidly amplifying these avalanches,' Pasko said. 'In addition to being produced in very compact volumes, this runaway chain reaction can occur with highly variable strength, often leading to detectable levels of X-rays, while accompanied by very weak optical and radio emissions. This explains why these gamma-ray flashes can emerge from source regions that appear optically dim and radio silent.' The international study was published Monday in the Journal of Geophysical Research.
The Independent
30-07-2025
- Science
- The Independent
What happens right before lightning strikes? Scientists have solved the mystery
Scientists say they've finally solved the mystery behind what happens just before lightning strikes. While famous inventor and U.S. Founding Father Benjamin Franklin discovered the connection between lightning and electricity back in 1752, experts still had not fully understood the journey from the cloud to the ground more than 270 years later. 'Our findings provide the first precise, quantitative explanation for how lightning initiates in nature," Victor Pasko, a professor of electrical engineering in the Penn State School of Electrical Engineering and Computer Science, said in a statement announcing the findings. "It connects the dots between X-rays, electric fields and the physics of electron avalanches." So, what's the deal with the atmospheric processes that trigger the giant, explosive sparks of electricity that can heat the air to a temperature five times hotter than the surface of the sun? According to Pasko and his team, the powerful chain reaction works similarly to an invisible pinball machine. Inside the storm clouds, strong electric fields speed up electrons that crash into molecules, such as nitrogen and oxygen. The reactions produce electromagnetic radiation commonly known as X-rays, as well as even more electrons and high-energy photons. Photons are the fundamental particles that make up light. After this, the lightning bolts are born. Atmospheric scientists knew how charged particles react within clouds. Protons rise and electrons descend toward the ground, resulting in a positive electric charge building on the ground. When that positive charge 'reaches out' to the approaching negative charge and the channels connect, the electrical transfer is what we see as lightning, according to the National Oceanic and Atmospheric Administration. To reach these new conclusions, the international authors used mathematical modeling, simulating the physical conditions in which a lightning bolt is likely to originate. 'We explained how photoelectric events occur, what conditions need to be in thunderclouds to initiate the cascade of electrons, and what is causing the wide variety of radio signals that we observe in clouds all prior to a lightning strike,' Zaid Pervez, a doctoral student in electrical engineering, said. 'To confirm our explanation on lightning initiation, I compared our results to previous modeling, observation studies and my own work on a type of lightning called compact intercloud discharges, which usually occur in small, localized regions in thunderclouds.' They also sought to explain observations of what is known as 'dark lightning' or a terrestrial gamma-ray flash. The invisible X-ray bursts are comprised of the flashes, which are produced in our atmosphere. They're often produced without flashes of light and radio bursts, which are familiar hallmarks of lightning during stormy weather. The researchers wanted to know why. 'In our modeling, the high-energy X-rays produced by relativistic electron avalanches generate new seed electrons driven by the photoelectric effect in air, rapidly amplifying these avalanches,' Pasko said. 'In addition to being produced in very compact volumes, this runaway chain reaction can occur with highly variable strength, often leading to detectable levels of X-rays, while accompanied by very weak optical and radio emissions. This explains why these gamma-ray flashes can emerge from source regions that appear optically dim and radio silent.'
Ammon
29-07-2025
- Science
- Ammon
Physicists discover new cosmic mechanism behind lightning formation
Ammon News - A significant breakthrough by Pennsylvania State University researchers, led by Victor Pasko, has provided the first quantitative explanation for precisely how lightning initiates. This groundbreaking work has revealed the powerful chain reaction that triggers lightning. In the study published on Monday in the Journal of Geophysical Research, the authors described how they determined strong electric fields in thunderclouds accelerate electrons that crash into molecules like nitrogen and oxygen, producing X-rays and initiating a deluge of additional electrons and high-energy photons, the perfect storm from which lightning bolts are born. 'Our findings provide the first precise, quantitative explanation for how lightning initiates in nature," Pasko said. "It connects the dots between X-rays, electric fields and the physics of electron avalanches." The team used mathematical modelling to confirm and explain field observations of photoelectric phenomena in Earth's atmosphere - when relativistic energy electrons, which are seeded by cosmic rays entering the atmosphere from outer space, multiply in thunderstorm electric fields and emit brief high-energy photon bursts. This phenomenon, known as a terrestrial gamma-ray flash, comprises the invisible, naturally occurring bursts of X-rays and accompanying radio emissions. 'By simulating conditions with our model that replicated the conditions observed in the field, we offered a complete explanation for the X-rays and radio emissions that are present within thunderclouds,' Pasko said. 'We demonstrated how electrons, accelerated by strong electric fields in thunderclouds, produce X-rays as they collide with air molecules like nitrogen and oxygen, and create an avalanche of electrons that produce high-energy photons that initiate lightning.' Zaid Pervez, a doctoral student in electrical engineering, used the model to match field observations - collected by other research groups using ground-based sensors, satellites and high-altitude spy planes - to the conditions in the simulated thunderclouds. 'We explained how photoelectric events occur, what conditions need to be in thunderclouds to initiate the cascade of electrons, and what is causing the wide variety of radio signals that we observe in clouds all prior to a lightning strike,' Pervez said. 'To confirm our explanation on lightning initiation, I compared our results to previous modelling, observation studies and my own work on a type of lightning called compact intercloud discharges, which usually occur in small, localized regions in thunderclouds.' Published by Pasko and his collaborators in 2023, the model, Photoelectric Feedback Discharge, simulates physical conditions in which a lightning bolt is likely to originate. The equations used to create the model are available in the paper for other researchers to use in their own work. In addition to uncovering lightning initiation, the researchers explained why terrestrial gamma-ray flashes are often produced without flashes of light and radio bursts, which are familiar signatures of lightning during stormy weather. 'In our modelling, the high-energy X-rays produced by relativistic electron avalanches generate new seed electrons driven by the photoelectric effect in air, rapidly amplifying these avalanches,' Pasko said. He added, 'In addition to being produced in very compact volumes, this runaway chain reaction can occur with highly variable strength, often leading to detectable levels of X-rays, while accompanied by very weak optical and radio emissions. This explains why these gamma-ray flashes can emerge from source regions that appear optically dim and radio silent.' WAM
