This project will use three imaging Doppler spectrometers to study wind and temperature in the Earth's thermosphere from about 120 to 240 km altitude over a grid spanning approximately 2000 x 1300 km in latitude and longitude respectively. Within the field of view some volumes will be observed tri-statically by all three instruments allowing for the first time unambiguous spatial mapping of the three vector components of the thermospheric wind field over an extended region. There will in addition be extended bi-static and mono-static coverage as well. This new Doppler imaging array will be applied to the following four science questions: 1) Do thermospheric wind and temperature fields contain local structure arising because the wind field can become dynamically unstable? 2) What is the spatial distribution of vertical wind disturbances in the auroral thermosphere? 3) How do thermospheric gravity waves perturb thermospheric winds and temperatures? 4) How do small-scale wind gradients affect dispersion of thermospheric air masses?
