October 19, 2025 D. Arnas, R. Linares “Approximate Analytical Solution to the Zonal Harmonics Problem Using Koopman Operator Theory” Journal of Guidance Control and Dynamics [07315090] 44.11 (2021): 1909-1923. Print. Share this 44.11 (2021): 1909-1923. Print."] Related Stories See all news ARCLab for Space.com: Is low Earth orbit getting too crowded? New study rings an alarm bell New prediction model could improve the reliability of fusion power plants See all news