LADAR

http://vulcan.wr.usgs.gov/Volcanoes/MSH/Eruption04/Monitoring/ImagesGraphics/LIDAR_crater_dome_sept03_and_nov04_animated_small.gif

LIDAR, or Light Detection And Ranging, is a method, much like radar, that uses pulses of scattered light to form an image. This image shows the topography of Mount St. Helens, and is actual an animation, switching between two LIDAR images, to show the changes occuring in the crater of Mt. St. Helens