MCA: Building Science and Engineering Capacity in Very Low Earth Orbit (vLEO)

The project addresses the critical need for convergence research at the intersection of geospace science and aerospace engineering. Very low Earth orbit (vLEO), which overlaps with the lower thermosphere and ionosphere, has recently emerged as one of the most exciting new frontiers for space operations, offering advantages in high-resolution Earth imaging, faster data transfer, and lower launch costs along with a benign radiation environment and a self-cleaning orbit. Despite those benefits, vLEO still lacks physical understanding. The project utilizes a novel approach to strengthen interdisciplinary collaborations: geospace scientists focus on understanding the fundamental physical processes governing the near-Earth space environment, whereas aerospace engineers prioritize detailed, localized modeling to support the design and operation of vLEO spacecraft. This interdisciplinary project will integrate the approaches from these different fields and develop new predictive, cross-regime modeling capabilities to support robust and efficient vLEO space operations. The outcomes include efficient vLEO operations, enhancing U.S. competitiveness in commercial space technologies, strengthening national defense capabilities, and enhancing cross-disciplinary research that builds capacity in STEM. The proposed research aims to establish a convergence research framework that integrates rarefied gas and continuum fluid dynamics to enable unified cross-regime, multi-physics approach to the Very low Earth orbit (vLEO) space environment modeling. The specific objectives are to (i) develop a unified cross-regime modeling framework by embedding relevant vLEO physics into Direct Simulation Monte Carlo (DSMC); (ii) build convergence research capacity by establishing an interdisciplinary team structure, developing shared computational infrastructure, and fostering cross-disciplinary Ph.D. training; and (iii) demonstrate and evaluate the prototype framework in a representative, limited-scope vLEO environmental scenario to assess cross-regime consistency and scalability for future applications. The resulting DSMC datasets will serve as training data for developing data-driven closure techniques adapted from computational fluid dynamics to rarefied gas dynamics, enabling the modeling framework scale to realistic vLEO applications. The project advances understanding of cross-regime gas flow interactions in vLEO, provides a predictive modeling framework, and establishes a foundation for interdisciplinary convergence that enhances the practical utility of space physics in alignment with NSF priorities. It addresses the critical scientific challenge of the transitional rarefied gas regime in vLEO by integrating fundamental knowledge of near-Earth space environment processes with high-fidelity aerospace computational modeling approaches, including DSMC. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.