水火山上空的闪电

2025年7月27日

Lightning over the Volcano of Water
Image Credit: Sergio Montúfar (Pinceladas Nocturnas)

Explanation: Have you ever watched a lightning storm in awe? You’re not alone. Details of what causes lightning are still being researched, but it is known that inside some clouds, internal updrafts cause collisions between ice and snow that slowly separate charges between cloud tops and bottoms. The rapid electrical discharges that are lightning soon result. Lightning usually takes a jagged course, rapidly heating a thin column of air to about three times the surface temperature of the Sun. The resulting shock wave starts supersonically and decays into the loud sound known as thunder. On average, around the world, about 6,000 lightning bolts occur between clouds and the Earth every minute. Pictured in July 2019 in a two-image composite, lightning stems from communication antennas near the top of Volcán de Agua (Volcano of Water) in Guatemala.

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水火山上空的闪电
影像提供: Sergio Montúfar (Pinceladas Nocturnas)

说明: 你是否曾敬畏莫名的看着雷暴系统吗？其实上，许多人都有过相同的感受。虽然闪电的详细成因仍在研究中，但我们知道在某些云层内部，上升气流会导致冰晶和雪粒互相碰撞，进而在云顶与云底之间逐渐造成电荷分离，最终产生瞬间的放电现象，也就是我们熟悉的闪电。闪电通常沿着锯齿状、曲折不规则的路径迅速前进，并将通道内空气瞬间加热至约为太阳表面三倍的高温。剧烈且急促的加热所产生的震波自通道中骤然爆发，以超音速穿过空气，最终化作为轰然雷鸣回荡天际。据估计，全球平均每分钟约有6,000次闪电在云层与地球之间发生。这张主题影像叠合自2019年7月拍摄的二张相片，画面中划破夜空的闪电，则始于危地马拉的水火山（Volcán de Agua）山顶附近的通讯天线。