Lightning over Chile's Puyehue-Cordón Caulle volcano complex in 2011. "The water and frozen-ash particles, said McNutt—who's found volcanic plumes to be surprisingly water rich—rub against each other. As with shuffling shoes on carpet, the contact produces static charges." Via http://j.mp/M4ni1D (larger version is at http://j.mp/KXljrg)

Lightning over Chile's Puyehue-Cordón Caulle volcano complex in 2011. "The water and frozen-ash particles, said McNutt—who's found volcanic plumes to be surprisingly water rich—rub against each other. As with shuffling shoes on carpet, the contact produces static charges." Via http://j.mp/M4ni1D (larger version is at http://j.mp/KXljrg)