In April 2010, a volcano in Iceland erupted sending a fume of ash into the jet stream. This ash quickly reached major cities in the northern and western Europe. Thousands of people were stranded in the airports around the world. 20 Countries had closed their airspace for 6 days. Economic impact was estimated at $5 Billion.
Volcanoes emit clouds of ash and Sulphur Dioxide gas. These gas particles are highly dangerous for the glasses of air jets traveling in the sky. They can damage aircraft and disrupt air traffic. The ash clouds are difficult to spot away from the volcano because they don’t show up on air born weather radar.
Hence, NASA with the help of advance science and technology found the way to track dangerous volcano clouds. Data from NASA earth-observing satellites is improving the ability to detect and forecast the hazard to aviation.