Sideways-striking "bolts from the blue" can hit the ground miles from the thunderhead. They appear to be created when a very intense negative charge layer is formed near the ground and positive layers get out of kilter. The bolt of lightning then slips out the side of the cloud and continues diagonally towards more distant ground. Giant blue jets shoot up from doubly tall thunderheads that generally only form in the tropics. A very intense negative charge in the gut of such a thunderhead can send a charge upward toward a less intense positive layer and overshoot it into space. "It's always easier to go upwards," said Riousset. That's because the thinner air moves electricity better, he explained. But more significant than all these details is how the new work makes sense of lightning in a way that's not been done before, said Earle Williams, a lightning research scientist at the Massachusetts Institute of Technology in Boston. "Lightning has always been seen as something chaotic," Williams told Discovery News. But more than two centuries since Benjamin Franklin started studying lightning, there is finally a theory that explains the phenomenon -- in all its varied forms. Related Links: |
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