Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

2012 July 30
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Ash and Lightning Above an Icelandic Volcano
Image Credit & Copyright: Sigurður Stefnisson

Explanation: Why did the picturesque 2010 volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas. The Eyjafjallajökull volcano in southern Iceland began erupting on 2010 March 20, with a second eruption starting under the center of a small glacier on 2010 April 14. Neither eruption was unusually powerful. The second eruption, however, melted a large amount of glacial ice which then cooled and fragmented lava into gritty glass particles that were carried up with the rising volcanic plume. Pictured above during the second eruption, lightning bolts illuminate ash pouring out of the Eyjafjallajökull volcano.

Tomorrow's picture: minutes before mars

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Authors & editors: Robert Nemiroff (MTU) & Jerry Bonnell (UMCP)
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