Designed to make the first-ever global survey of Earth's surface water, the Surface Water and Ocean Topography, or SWOT, satellite will collect detailed measurements of how water bodies on Earth change over time. The satellite will survey at least 90 percent of the globe, studying Earth's lakes, rivers, reservoirs and oceans at least twice every 21 days to improve ocean circulation models, and weather and climate predictions, and aid in freshwater management around the world.