The Coriolis satellite will demonstrate the ability to measure wind speed and direction on the world's oceans. In addition, on-board instruments will track coronal mass ejections from the Sun as they propagate through the interplanetary medium, providing advance warning of geomagnetic disturbances. The instruments that will accomplish these tasks are named WindSat and SMEI. 

The Coriolis spacecraft is a three-axis stabilized, nadir-pointing satellite that will be inserted into a 830 km sun synchronous polar orbit at 98.7° inclination. It is approximately 21 x 8 x 7 ft in size and has a launch mass of about 817 kg (1800 lbm). An on-board hydrazine propulsion system will be used to circularize the initial orbit and provide orbit maintenance as the mission progresses. Coriolis is expected to operate for a minimum of three years.

The WindSat payload will demonstrate the capability of a polarimetric microwave radiometer to measure the ocean surface wind vector on a global scale. This will be the first such instrument to provide wind direction as well as speed, and will allow a 3X increase in performance over current systems. The multi-frequency radiometer will operate in the 6.8, 10.7, 18.7, 23.8, and 37 GHz ranges. The US Navy will use a real time S-band tactical downlink to distribute radiometer data to deployed fleet units. This technology demonstration is an important pathfinder for the National Polar-orbiting Operational Environmental Satellite System (NPOESS).

The Solar Mass Ejection Imager (SMEI) payload will use an all-sky camera assembly to monitor and track coronal mass ejections. Algorithms will be used to convert this data into a 1-3 day warning of significant geomagnetic disturbances on Earth. The three SMEI cameras provide a 3° x 180° field of view with a 1° resolution.

Coriolis is a DoD Test Program mission to fly Naval Research Laboratory (NRL) and Air Force Research Laboratory (AFRL) payloads. Spectrum Astro’s contract was competitively awarded in March 1999 through NASA Goddard’s Rapid Spacecraft Development Office.