What goes on when lightning strikes?

One lightning flash could run a whole power station – and there are 8 million strikes around the Earth every day. We still don't know what triggers the phenomenon, although a new theory proposes a role for cosmic raysA new theory from Russian researchers suggests that lightning may be a by-product of cosmic rays. Surprisingly, despite studying lightning for centuries, we are still not sure what triggers it.Divine attributionIn ancient times, the drama of thunder and lightning so clearly went beyond human scale that the phenomenon was handed wholesale to the gods. The Greeks had Zeus, the Romans Jupiter. At the head of the Hindu pantheon was Indra, while Norse mythology gave us Thor – all wielders of thunderbolts. Even when thunderstorms were not ascribed directly to the activity of a divine being, they were considered a disturbing premonition. Pliny the Elder, writing in the first century AD, called them prophetic, direful and accursed.Traditionally, thunder and lightning were treated as separate, related, phenomena, because sound travels far slower than light. When a ripple of lightning splits the sky, the light travels towards us at 300,000 kilometres per second. By comparison, the noise ambles along at just 340 metres per second. After the near-instantaneous flash, we have to wait for the sound to catch up. If a thunderstorm is 10km distant, the delay will be around 29 seconds.Famously, American politician and scientist Benjamin Franklin is said to have tested lightnin...
Source: Guardian Unlimited Science - Category: Science Authors: Tags: Meteorology World news Natural disasters and extreme weather Features UK news The Observer Science Source Type: news