This spectacular pic was taking by the NASA's ISS. It belongs to the eruption of Saychev Peak on Matua Island on June 12th. You can see the steam (white oval on top), the cloud of dust and how the violence of the eruption forces the clouds to give space: a kind of ring due to the atmospheric shockwave.
It takes some time to open the image, but is worth the wait.
[Via io9]
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