Aswan Dam (upper center of image) and Lake Nasser along the Nile River. The dam controls the flow of the Nile River forming Lake Nasser. The light-colored areas in the lake are where the sun is reflecting off the surface of the water. These areas are fairly calm and not disturbed by wind gusts, enabling the sun glint to show water current patterns on the surface. The Aswan runway is seen as a dark set of lines just west of the Aswan Dam. Click on photo for higher resolution. Image courtesy of NASA.