Analysis of Shock-Layer Radiative Heating for a Mars Sample Return Sample Retrieval Lander Concept

The radiative heating environment for the Mars Sample Return Sample Retrieval Lander is analyzed for the 8 km/s entry interface velocity resulting from a potential 2031 launch date. This is notably faster than previous Mars missions like Mars Science Laboratory and Mars 2020, which had entry interface velocities around 6 km/s. The increased speed shifts the dominant radiative mechanisms on the vehicle forebody from [Formula: see text] infrared bands to CO fourth positive and CN bands, which are more sensitive to nonequilibrium flowfield and radiation models than the [Formula: see text] infrared bands. To address the significant uncertainties in these nonequilibrium models, this work compiles the best available nominal modeling parameters and their corresponding uncertainties. At the peak radiative heating forebody surface location, the upper limit parametric uncertainty is near 100%, while on the afterbody, the upper limit parametric uncertainty is near 50%. The shock-tube informed bias analysis results in values 10% higher than the nominal on the forebody and 24% higher on the afterbody. An approach is suggested for combining the parametric uncertainty and shock-tube informed bias into a radiative heating margin, which may be adjusted to the level of conservatism desired by the project.