In support of NASA's Artemis campaign, NASA JSC leads the Gateway Program in building a space station in lunar orbit with international and commercial partnerships. The lunar Gateway space station will host crew and scientific research, and will facilitate the development of key technologies and capabilities enabling future Moon and Mars exploration. [1] Gateway will experience a complex external molecular contamination environment with contributions from materials outgassing, venting, and thruster pluming sources. [2] The Gateway Induced Environments and Thermal teams have worked with JPL Contamination Control to develop a framework for system-level external molecular contamination modeling, [3] which has now been used to analyze molecular outgassing transport, deposition and induced optical property degradation across several Gateway configurations. This framework has been extended to incorporate separate, detailed payload-level outgassing models and has seen new inputs as materials selection proceeds, as surrogate outgassing datasets are identified, and as physics-based outgassing models are developed and validated. [4] In this high-level presentation, the status of lunar Gateway external molecular outgassing contamination and optical property degradation models will be reviewed, including updates to the lunar Gateway external system-level model inputs and model framework; a brief description of the linkage of payload-level and system-level models; and developments in JPL multispecies outgassing modeling and testing campaigns.

[1] Gateway Overview, https://www.nasa.gov/reference/nasas-gateway-program. Retrieved 28 Feb. 2024.

[2] Soares, C.E., Mikatarian, R., Proc. 9th Int'l Symposium on Materials in the Space Env. (2003).

[3] Hoey, W.A., Martin, M.G., Steagall, C.A., Soares, C.E., Shallcross, G.S., Worthy, E.S., Proc. 15th Int'l Symposium on Materials in the Space Env. (2022).

[4] Roussel, J-F.R., Lansade, D., Leclercq, L., Soares, C.E., Alred, J.M., Martin, M.G., Wong, A.T., Anderson, J.R., Faye, F., Rioland, G., Journal of Spacecraft and Rockets. (2023).