This company manufactures high-speed cameras able to observe a lightning striking a rod on the top of a building. The CMOS sensor allows 40K (forty thousand!) frames per second (fps) at 512 x 256 resolution. The results show the lightning flash speed at 60 miles (96 km) per second and two connecting leaders: One from the storm clouds down to the rod and another from the rod up to the clouds. This explains why people that have not been struck directly still may be hurt by the upward currents from their heads or shoulders trying to connect with the charge coming down.
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