The eruption of Eyjafjallajökull volcano in spring 2010 freed the crater, to the left in the image, of its ice cover. This three-dimensional elevation model, created using data from the two radar satellites TanDEM-X and TerraSAR-X, shows that the nearby volcano Katla (right) is probably still active; the small indentations indicate that the ice sheet cover it is melting and collapsing.