As if thrown from the hands of Zeus himself, a dramatic video captures the breathtaking moments lightning seemingly shoots out of Indonesia’s Krakatau volcano.
The minute-long clip filmed by Dr Richard Roscoe from nearby Rakata Island shows dramatically hellish footage of lava pouring over Anak Krakatau (Son of Krakatau), the most active part of the volcano, as ash plumes out and volcanic “bombs” are seen setting fire to nearby vegetation, causing large splashes as they plummet into the ocean surrounding the island. During the October 24 to 28 eruption, satellite data indicated ash plumes rose to altitudes of 914-2,130 meters (3,000-7,000 ft) – but we’re here to talk about the bedazzling volcanic lightning.
In general, for lightning to occur a large separation between two masses needs to happen that ultimately becomes big enough to overpower resistance in the air and conduct electricity in the form of lightning. But the dazzling volcanic lightning phenomena is a bit more mysterious. It’s been observed in the past but remains difficult to study since most volcanoes are in remote parts of the world, erupt sporadically, and, you know, there's a gushing outflow of hot lava to deal with (although scientists have managed to record the sound of volcano thunder).
In recent years, scientists have been able to use very high frequency (VHF) radio emissions and electromagnetic waves that help them to see the lightning inside ash plumes as it happens in two phases, reports Earth Sky. The “eruptive phase” is a period of intense lightning that forms immediately or just after the eruption near to the crater, ejecting positively charged particles from the volcano. The second “plume” phase shows the lightning as it forms in the ash plume downwind of the crater. The origins of these charged particles is still unknown, but it’s believed some sort of charging process happens as material from within the volcano is ejected.
The incredible footage was captured by Dr Richard Roscoe from nearby Rakata Island. (c) Photovolcanica/Youtube
One theory is the ash that’s erupted starts of as a neutral rock. Heat and movement from within the volcano could charge it, and when that neutrally charged ash comes into contact with another electrostatically different objects, electrons can flow between the two. As Oregon State University explains, it’s sort of like when you rub a balloon against your head. When you pull the balloon away, hair becomes electrically charged and stretches towards the balloon. Cool, right ?
Located on Sunda Straight between Java and Sumatra, Anak Krakatau is an island volcano that appeared (broke water) in 1927 from the caldera of Krakatau's famous 1883 eruption that killed over 36,000 people, one of the most violent volcano eruptions in history.
It's smack dab in the Pacific Ring of Fire and is one of the most exciting volcanoes to watch, even though it is just a century old, thanks to its activity; several eruptions have been recorded ever decade since it appeared.