On April 15, 2010, the Moderate Resolution Imaging Spectroradiometer (MODIS) instrument on NASA's Terra spacecraft captured these images of the ongoing eruption of Iceland's EyjafjallajÃ¶kull Volcano, which continues to spew ash into the atmosphere and impact air travel worldwide. The left-hand, natural-color visible image shows a brownish, ash-laden plume streaming across the North Atlantic towards the United Kingdom. The right-hand image is a composite of thermal infrared channels. In this rendition, the ash plume appears red, due to the presence of silica-rich material, and the ice-rich clouds appear blue. These MODIS images do not show any evidence of sulfur dioxide clouds, which would appear yellow in the right image. It is likely that any sulfur dioxide signals were obscured by the large amounts of ash. Scientists expect to see a better expression of sulfur dioxide in later images of the plume as the ash settles over time.