The island of Sumatra suffered from both the rumblings of the
submarine earthquake and the tsunamis that were generated on
December 26, 2004. Within minutes of the quake, the sea surged
ashore, bringing destruction to the coasts of the northern
Sumatra. This pair of images from the Moderate Resolution
Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite
shows the Aceh province of northern Sumatra, Indonesia, on
December 17, 2004, before the quake and on December 29, 2004,
three days after the catastrophe. Though MODIS was not
specifically designed to make the very detailed observations
that are usually necessary for mapping coastline changes, the
sensor nevertheless observed obvious differences in the Sumatran
coastline. On December 17, the green vegetation along the west
coast appears to reach all the way to the sea, with only an
occasional thin stretch of white that is likely sand. After the
earthquake and tsunamis, the entire western coast is lined with
a noticeable purplish-brown border. The browni