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14/05/2018

Sakurajima Volcano with Lightning - Astronomy picture of the day - 2018 May 13

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Sakurajima Volcano with Lightning 
Image Credit & Copyright: Martin Rietze (Alien Landscapes on Planet Earth)
Explanation: Why does a volcanic eruption sometimes create lightning? Pictured above, the Sakurajima volcano in southern Japan was caught erupting in 2013 January. Magma bubbles so hot they glowed shot away as liquid rockburst through the Earth's surface from below. The featured image is particularly notable, however, for the lightning bolts caught near the volcano's summit. Why lightning occurs even in common thunderstorms remains a topic of research, and the cause of volcanic lightning is even less clear. Surely, lightning bolts help quench areas of opposite but separated electric charges. Volcanic lightning episodes may be facilitated by charge-inducing collisions in volcanic dust.Lightning is usually occurring somewhere on Earth, typically over 40 times each second.

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