Oil Slick in the Gulf of Mexico

Oil from the Deepwater Horizon rig lingered off the Mississippi Delta on July 4, 2010. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra captured this natural-color image the same day. The oil appears as an uneven light gray shape east-southeast of the delta.

© Image from NASA's Terra satellite - courtesy of the NASA EO-1 team

The oil was visible to MODIS on July 4 thanks to sunglint. Oil smoothes the surface of the water, making it a better mirror of sunlight. As a result, close to the Sun’s reflection, the oil is lighter than surrounding water. This is especially true between the Mississippi Delta and the Deepwater Horizon rig. East of the rig, however, sunglint lightens most of the water, making it difficult to distinguish a possible oil slick from oil-free water. Please see the links below for more information.

© Earth Observatory