Explanation:
Why does a volcanic eruption sometimes create lightning?
Pictured above, the
Sakurajima volcano
in southern Japan
was caught erupting early last month.
Magma bubbles so hot they
glow shoot away as liquid rock bursts through the
Earth's surface from below.
The above 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.
One hypothesis holds that catapulting magma bubbles or volcanic ash are themselves electrically charged, and by their motion create these separated areas.
Other 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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