As the huge plume of ash and steam from Iceland's Eyjafjallajökull volcano blew east-southeast, threatening to ground aircraft along its track, a NASA satellite captured the cloud in action.
The natural-color image was taken by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA's Terra satellite on April 15. The plume was just blowing past the Faroe Islands, which lie northwest of Scotland and halfway between Iceland and Norway. Then it arced slightly toward the north near the Shetland Islands, off the northeastern coast of Scotland.
The colors didn't just make for a pretty picture, as the tan hues indicated there was a fairly high ash content in the plume.
Unlike the soft, fluffy material that results from burned vegetation, volcanic ash contains tiny jagged particles of rock, which can be dangerous for aircraft. Once sucked into an airplane's turbines, the abrasive material can easily cause engine failure, though an aircraft's weather radar can't spot the ash.
While the eruption has made itself known, the volcano is also quite a presence, rising some 5,466 feet (1,666 meters) above sea level. The volcano began erupting for the first time in 190 years on March 20, 2010. The eruption opened a 2,000-foot (500-meter) fissure, and also produced lava fountains that built several hills of bubble-filled lava rocks along the vent. The second eruption began on Wednesday.
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