This UAVSAR interferogram shows active volcano Mount St. Helens (left) and dormant volcano Mount Adams, both in Washington state. The sensor collected data for this image during flights in July 2009 and August 2010 to compute the surface deformation that could indicate activity in the volcanoes' magma. No deformation was evident during this period.
NASA scientists periodically monitor subtle changes in volcanic activity with the Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) carried by a modified NASA C-20A (G-III) aircraft. ...
Developed by NASA's Jet Propulsion Laboratory in Pasadena, Calif., the UAVSAR uses a technique called interferometry to detect and measure very subtle deformations in Earth's surface. ...
UAVSAR provides a measurement system that complements satellite-based observations by providing rapid revisits and imaging of active volcanoes to better understand their deformation prior to, during or after an eruption.
Image credit: NASA
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