Megalightning ()

Synopsis:
Entirely new forms of Lightning have been discovered up to 1000 times bigger than any bolt previously seen. While normal lightning fires down below clouds, these giant bolts shoot up, stunning experts with images of lightning 80 kilometers high.

This lightning, six times more powerful than passenger planes are designed to withstand, may be the real killer in a spate of baffling air disasters.

And for the first time we can reveal the photograph that sparked a secret NASA enquiry.
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