The Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua satellite flew over the volcano at 1:30 p.m. local time (13:29:24 UTC, or 6:29:24 a.m. PDT) on April 15, capturing this false-color infrared image, as well as a visible image of the ash plume. The images show the ash cloud (in blue) enveloping Iceland and moving eastward over the Shetland Islands and onward to Europe. The ash clouds appear to be at an altitude of 3,658 meters (12,000 feet).

NASA works with other agencies on using satellite observations to aid in the detection and monitoring of aviation hazards caused by volcanic ash. More information on this NASA program is at: http://science.larc.nasa.gov/asap/research-ash.html . The ingestion of ash particles from such clouds can result in engine failure for aircraft.

Because infrared radiation does not penetrate through clouds, AIRS infrared images show either the temperature of the cloud tops or the surface of Earth in cloud-free regions. The lowest temperatures (in purple) are associated with high, cold cloud tops. In cloud-free areas the AIRS instrument will receive the infrared radiation from the surface of the Earth, resulting in the warmest temperatures (orange/red).