The proposed diagnostics will support the development of spacecraft for entering planetary atmospheres, such as Mars and Venus, as well as reentry to Earth?s atmosphere. Radiative heat transfer to the vehicle during atmospheric entry can be severe, yet predictive methods are hampered by a lack of data for validating models. The proposed tools will provide electron number density and electron temperature thus yielding key insight into radiative properties of the plasma formed post-shock during atmospheric entry and help improve the fidelity of current measurement techniques. Information obtained from these diagnostics should aid in the design of advanced space exploration vehicles, and in the improvement of prediction models that simulate radiative heat transfer used in the design of thermal protection systems (TPS). This can help in reducing the design margins of TPS and thus result in increased mission payload capability.
The ability to accurately measure shock location, shock velocity, and electron number density would be attractive to research on hypersonic vehicles, and should find use in research facilities employed in the development of high-speed missiles and aircraft. In particular, the Air Force has programs to develop hypersonic vehicles that would benefit from these diagnostics. Other Air Force programs that would benefit include those on the development of Hall thrusters for satellite propulsion, which have a need for accurate, time-resolved electron number density measurements.