Lightning over a volcanic eruption in Chile

This dramatic flash is a lightning storm raging at the top of a volcano. The light show, observed at the peak of the Calbuco volcano in Chile in April 2015, is a phenomenon known as volcanic lightning. In a recent Geology paper, co-author Steve McNutt, a volcanologist at the University of South Florida, explained that this happens when particles of ash and lava shoot out of the crater and rub together, generating bursts of static electricity. "Inside the flash, the temperature can reach up to 30,000°C, and it can melt ash and rock particles," McNutt says.