The NASA Scatterometer (NSCAT) was a Ku-band (13.995 GHz) dual fan-beam scatterometer. Its primary purpose is to provide all-weather ocean surface wind vector measurements over the ice-free global oceans.

NSCAT was launched aboard the Japanese satellite Midori, also known as the Advanced Earth Observing Satellite (ADEOS), on August 16, 1996. The NSCAT mission was a partnership between the National Space Development Agency (NASDA) of Japan, NASA, and NASA's Jet Propulsion Laboratory. After the short-lived success of the Seasat scatterometer in 1978, there was much anticipation for the research and development of the NSCAT instrument, which was expected to provide the first long-term data record of global high resolution ocean surface wind vector measurements. The unfortunate premature power failure of the ADEOS spacecraft resulted in a termination of the NSCAT mission on June 30, 1997. While in operation, NSCAT provided approximately 70% global ice-free ocean coverage every day with a measurement footprint of 25 km. Nearly 10 months of continuous global ocean surface wind vector data was provided by NSCAT, representing an unprecedented achievement by NASA.