Light Pillar over Volcanic Etna

Explanation: What happening above that volcano? Something very unusual -- a volcanic light pillar . More typically, light pillars are caused by sunlight and so appear as a bright column that extends upward above a rising or setting Sun . Alternatively, other light pillars -- some quite colorful -- have been recorded above street and house lights. This light pillar , though, was illuminated by the red light emitted by the glowing magma of an erupting volcano . The volcano is Italy 's Mount Etna , and the featured image was captured with a single shot a few hours after sunset in mid-June. Freezing temperatures above the volcano's ash cloud created ice-crystals either in cirrus clouds high above the volcano -- or in condensed water vapor expelled by Mount Etna . These ice crystals -- mostly flat toward the ground but fluttering -- then reflected away light from the volcano's caldera .

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