A lightning burst of chemistry

Thunderstorm

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Trying to understand the chemistry that occurs around immensely powerful but short-lived lightning bolts is a feat in itself. James Mitchell Crow looks for a flash of inspiration

A flash of lightning can light up the sky. Each lightning bolt is only about 2–3cm thick, but carries so much energy it heats the surrounding air to 30,000°C, far hotter than the surface of the Sun. Where lightning meets the ground, a direct hit is easily powerful enough to blow apart mature trees. And each bolt is equally destructive all the way along its typical 5km length through the air. Any molecule in the bolt’s vicinity will be torn apart into its component atoms. Most of those molecules will be dinitrogen (N2) and molecular oxygen (O2), the two major components of the air. As these atoms cool and recombine, they can find themselves with new partners.

Recent research suggests lightning’s influence on the chemistry of the atmosphere reaches far further than previously thought.