The eruption of Hekla <a href="https://en.wikipedia.org/wiki/August_17" class="extiw" title="en:August 17">en:August 17</a> <a href="https://en.wikipedia.org/wiki/1980" class="extiw" title="en:1980">en:1980</a> at approximately 13:40.  It was taken from a position 4 km to the northeast of the volcano which had been erupting for about 10 minutes when the photograph was taken.  The lighter steam in the middle distance marks the meltwater path <i>jökulhlaup</i> of the summit glacier that had just melted and literally cartwheeled down the mountain.  The noise of the eruption was akin to a jet engine roaring at this point.
<a href="https://en.wikipedia.org/wiki/User:Oxonhutch" class="extiw" title="wikipedia:User:Oxonhutch">Oxonhutch</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>
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