Lightning Jets and Sprites

The ancient Greeks might have thought Zeus was furious with heaven itself. The power of lightning strikes and Sprites, that shoot upwards from storm clouds has been measured for the first time – and they turn out to be every bit as powerful as normal lightning.

First caught on camera in 2003, "gigantic jets" shoot upwards from thunderclouds and can reach altitudes above 80 kilometres. But it wasn't until 21 July last year that Steven Cummer at Duke University in Durham, North Carolina, and his colleagues managed to measure the electrical discharge from a single gigantic jet, released from tropical storm Cristobal.

"No one had been very close to one with the right radio instrumentation before," Cummer says. "So we didn't know whether they just petered out without doing anything much, or whether they actually took some charge and dumped it somewhere."