Landsat 8 reveals algal bloom off Brazil's coast near Sao Paulo, 2017

In early September 2017, Landsat 8 captured this image of what looked like an oil spill off the coast of Brazil, near Sao Paulo. The "oil" turned out to be a vast algal bloom that covered more than 100 km. This bloom was the result of a species of tiny dinoflagellate that multiplied quickly to produce astronomical numbers -- enough to color the ocean water.