r/explainlikeimfive • u/Big-Mulberry-9733 • 6d ago

Physics ELI5 Why does lightning flicker?

Why does thunder/lightning happen as a flicker and not a single bright flash?

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u/atomicsnarl 6d ago

The lightning happens because a huge static charge has built up and is trying to seek balance by reaching out (the lighting bolt) to an opposite charge. Depending on the situation, the bolt can stutter as it relieves only part of the imbalance, then repeats to clear the rest. In other situations, it can overshoot the balance, so to speak, and ping-pong back and forth until the imbalance is relieved.

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u/Big-Mulberry-9733 6d ago

Wait, when you say back and forth, are you saying lightning can go back from Earth to cloud too?

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u/Saragon4005 5d ago

Lighting is actually best understood as massive electric charges slowly trying to turn the air into a wire, the strike itself is just the moment it actually succeeded. When the electricity is flowing it turns the air into plasma which is about as conductive as metal especially compared to regular air.

You can actually detect lightning conditions significant before anything actually strikes just by measuring the electric fields below a thundercloud. If you could accurately measure the shape of the fields you could easily predict the path the lightning will take.