The plumes from some erupting volcanoes, such as the Sakurajima volcano in Japan, develop electrical charges that flash over the crater, lighting up the sky and sending sound waves that resemble thunder. What causes these sound and light shows?
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When eruption begins, particles which are charged are dispatched to the atmosphere. The particles tumble and collide against each other, contributing to more charge. Once they disintegrate to different directions, charge separation occurs, causing giant rubbing sound and lightning.
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