Several days ago, a volcano that had been dormant for 9,000 years near the coast of Chile erupted spectacularly, hurling liquified metals and lightning many miles into the sky. The results, which you see here, are called a "dirty thunderstorm," and are quite rare. Nobody is certain what causes them, but according to National Geographic it's believed to be "the result of rock fragments, ash, and ice particles in the plume collid[ing] to produce static charges—just as ice particles collide to create charge in regular thunderstorms." Want to see a photo of the volcano plume from space?

The volcano spewed debris twenty miles up into the atmosphere. It erupted on Friday, May 2, and erupted again yesterday. Over 4,000 locals have fled, but luckily everyone was able to get away safely. The lava isn't the fast-moving kind, but rather a slow-moving creep of material. So nobody is being menaced by a rapidly-moving wall of liquid rock. Photographs via National Geographic.

Second Eruption in Chile [London Guardian]