In this image, we see blue silt off the southern coast of Louisiana as the Mississippi River flows off into the Gulf of Mexico. The brightness and shade of blue depends on the density of the silt and the depth of the silt-carrying currents in the water. The small bright dots in the scene are fishing boats and oil platforms.

In this image, we see blue silt off the southern coast of Louisiana as the Mississippi River flows off into the Gulf of Mexico. The brightness and shade of blue depends on the density of the silt and the depth of the silt-carrying currents in the water. The small bright dots in the scene are fishing boats and oil platforms.

Credit

Image taken by the Enhanced Thematic Mapper instrument onboard the Landsat-7 satellite. Source: U.S. Geological Survey (USGS) Landsat Missions Gallery, "Louisiana Silt," U.S. Department of the Interior / USGS.

ENLARGE