Bhanu Kumar (University of Michigan) will visit us and give a talk on Tuesday 7th October in Carslaw 375 at 11am (note unusual day, time, location). Title: Mean motion resonant phenomena, orbits, and transfers in planet-moon systems Abstract: In this talk, I will discuss resonant orbits and the phenomenon of mean-motion resonance overlapping, which generate natural heteroclinic, propellant-free pathways that spacecraft can follow to change their semimajor axis. This is useful for low-fuel and/or low-energy space mission trajectory design. I will start by describing some recent related results from the Earth-Moon system, with applications to missions throughout cislunar space. Then, moving to the more complicated systems of the outer planets, which have multiple moons, I will discuss secondary resonant phenomena which occur inside the normally hyperbolic invariant manifolds formed by unstable mean motion resonant orbit families. The secondary resonances inside these manifolds are found to overlap in some cases, resulting in a total change of structure for the more unstable members of such familiesâprecisely the orbits most useful for outer planet tour design.