A new NASA satellite that will peer into the topmost layer of Earth's soils to measure the hidden waters that influence our weather and climate is in final preparations for a January 29, 2015 dawn launch from California. The Soil Moisture Active Passive (SMAP) mission will take the pulse of a key measure of our water planet: how freshwater cycles over Earth's land surfaces in the form of soil moisture. This data will be used to enhance scientists' understanding of the processes that link Earth's water, energy and carbon cycles.