English: On September 5, 2017, the Moderate Resolution Imaging Spectroradiometer (MODIS) acquired a beautiful true-color image of the Caspian Sea.

The Caspian Sea covers about 143,200 square miles (371,000 square kilometers), making it the world’s largest inland body of water measured by surface area. The Caucasus Mountains site to the west of the Caspian Sea, while the Central Asian steppe lies to the west. Clockwise from the north the five countries that border the waters are Kazakhstan, Turkmenistan, Iran, Azerbaijan, and Russia.

The northern part of the lake is visibly different that the southern portion. A driving factor in this difference is water depth. The northern part of the lake is only 16 to 20 feet deep, while the southern end drops more than 3,300 feet (1,000 meters). Some of the largest rivers feed into the northern in, carrying sediment that contributes to the coloration of the north. The largest inflow comes from the Volga River, which can be seen in at the northwest of the Caspian Sea. Blooms of algae or phytoplankton can also change the water color, both in the north and the south.