The European Space Agency’s two HydroGNSS satellites use an innovative technique called Global Navigation Satellite System (GNSS) reflectometry to quite literally ‘scout for water’.
This process involves the HydroGNSS satellites capturing L-band signals from navigation systems such as GPS and Galileo. These navigation satellites transmit L-band microwave signals that change when they are reflected off Earth’s surface. The HydroGNSS satellites will compare these reflected signals with the direct GNSS signals to reveal valuable information about the properties related to the water cycle, and more. Embracing the New Space concept, HydroGNSS is one of ESA’s new Scout missions being developed within the Earth Observation FutureEO programme.