And if I told you that a flash could arise without light or noise ? Not a flash. Not a rumble. Nothing. However, this phenomenon exists. American researchers have just proved it. And believe me, it’s as exciting as it is outstanding.
Flagles born of space: how cosmic particles trigger invisible thunderstorms
When you think of a thunderstormon imagine des dark cloudsof the Bright lightningthen the thunder who slams. But sometimes, none of these signs manifests. However, a electrical discharge does not happen at the heart of the cloud.
Scientists from the University of Penn State have highlighted an amazing phenomenon. He begins with the arrival of Very fast cosmic particleslike Protons from space. When they hit the atmosphere, they cause a Accelerated electron cascade.
Then these electrons hit the nitrogen molecules or ofoxygen in the air. Result: they emit X -rays and gamma very energetic. This radiation is sometimes enough to trigger a electrical dischargewithout the least visible lightning.
This phenomenon is called Terrestrial Gamma-ray Flash (TGF). It was observed for the first time in the 1990s. Since then, researchers have progressed, but it is only today that they finally understand the mechanisms.
Why these lightnings escape our eyes, our ears … and even our weather radars
So why are these discharges invisible? First, because they are very brief et very localized. Sometimes they only extend over A few tens of meters in a cloud.
Then the Product radiation is often too low to generate a visible lightning. And thewhere sonorein other words thunder, does not form If the energy is insufficient.
Another important point: these discharges last Less than a millisecond. A beat of eyelash. Impossible to perceive without very sensitive instruments.
However, we detect Between 50 and 500 per day in the world. And even if they are invisible to us, they could have a impact on planesTHE satellitesor communications radio.
Victor Christmasprofessor of electrical engineering at Penn State, summarizes it perfectly:
“This chain reaction can occur in very small areas and with variable intensity. It sometimes emits just enough X -rays to be captured, while remaining almost invisible and silent. »»
In other words, these Ghost lightning can arise from places that seem perfectly calm. No lightning. No noise. And yet a silent thunderstorm is played at high altitude.
A discovery that redefines weather, lightning and influence of cosmic particles
These mini-eclairs show that theatmosphere still hides many things. What we took for a simple calm cloud can, in reality, accommodate phenomena violent but imperceptible.
Thanks to their mathematical modelthe researchers managed to reconstruct, step by step, the required conditions when they started these discharges. They crossed satellite dataof the plane measurementsand statements at sol. A real scientific investigation.
What they describe is a electromagnetic chain reactionsupplied by particles from space. Everything remains silent, discreetmore electrically very active.
Therefore, this discovery Change our gaze on thunderstorms. She reminds us that Everything that is invisible is not inactive.
A peaceful sky can hide a Electron and X -ray ballet. Phenomena that thehuman eye does not perceive, but that the sciencelittle by little, manages to decode.
What if these Ghost lightning are still unknown today, they could tomorrow Rewrite our way of providing thunderstormsof Monitoring the airspaceor even Better understand our own planet.
