<p><strong><a id="ow_0" title="lightning" href="http://environment.nationalgeographic.com/environment/natural-disasters/lightning-profile.html">Lightning</a> crackles over <a id="ocvr" title="Japan" href="http://travel.nationalgeographic.com/travel/countries/japan-guide/">Japan</a> on Friday as ash and lava erupt from Shinmoedake peak, one of the calderas of the Kirishima <a id="o3h5" title="volcano" href="http://environment.nationalgeographic.com/environment/natural-disasters/volcano-profile/">volcano</a> complex. <br></strong></p><p>Shinmoedake began erupting Wednesday, coating nearby villages and farms with ash and prompting authorities to ask for voluntary evacuations within a 1.2-mile (2-kilometer) radius.</p><p>Volcanic lightning is still a mystery, though it may be that electrically charged silica—part of magma—interacts with the atmosphere when it flies out of a volcano, <a id="gsnf" title="Steve McNutt" href="http://www.aeic.alaska.edu/Input/steve/">Steve McNutt</a> of the Alaska Volcano Observatory told National Geographic News in February 2010.</p><p>(Also see <a id="xse:" title="pictures of volcanic lightning during a recent eruption of an Iceland volcano" href="http://news.nationalgeographic.com/news/2010/04/photogalleries/100419-iceland-volcano-lightning-ash-pictures/">pictures of volcanic lightning during a recent eruption of an Iceland volcano</a>.)</p>