The CSSL (combined sporadic structures and layers) payload: In situ observations of mesospheric sodium and related parameters

The existence of joint sporadic plasma/neutral layering phenomenon has been recognized. While various theories have been presented, it is clear that the study of plasma/neutral structuring down to meter scales is necessary in order to understand the underlying processes. Specifically, a comparison of small-scale (∼1 m)/large-scale (∼1 km) "electrical" structures with similar scale structures in the neutral sodium layer is required to uncover the layering physics. This task will be accomplished with the CSSL (Combined Sodium and Sporadic Layers) payload which is comprised of fore- and aft-nose-tip probes, special boom-mounted E field probes, and a bistatic, sodium lamp-based, CW lidar system. The objectives of the CSSL payload are: 1) To validate current models of mesospheric sodium chemistry (specifically, the relationship between Na and electron concentrations), 2) To explore the relationship between turbulence and Na fluctuations, and 3) To explore the relationship between high-latitude electric fields and the formation of Na anomalies. This paper will outline the scientific goals and discuss the design of the sensor systems for the CSSL payload.