May 1: Aaron J. Rosengren, University of California San Diego

• 1:30 p.m.
• 3100 Torgersen Hall
  
• Host: Shane Ross

 "Astro-Cartographies of Cislunar and Translunar Space"

Abstract. The Earth–Moon environment is best understood not as a single beyond-GEO region, but as a multiscale dynamical geography partitioned by secular transitions, resonant structure, and gateway topology. In this seminar I present a set of astro-cartographies of cislunar and translunar space that synthesize analytical averaging, semi-analytical resonance theory, restricted multi-body dynamics, and direct numerical mapping into a single spatiographic picture. This framework distinguishes the secularly dominated cislunar zone beyond the Laplace radius, the outer cislunar domain organized by interior lunar mean-motion resonances, the circumlunar gateway region associated with the Earth–Moon L1/L2 bottlenecks, and the translunar realm beyond the Moon, where exterior lunar and low-order solar resonances coexist within a mixed lunar–solar secular architecture.

I will show how orbit-averaged lunisolar theory furnishes the leading-order secular backbone of high-altitude circumterrestrial motion, how resonance atlases provide a dynamical cartography of the principal cislunar and translunar commensurabilities, and how global phase-space structure emerges through resonant periodic orbits, separatrices, and transport corridors. New chaos-indicator and fate-classification maps reveal the fine structure of these regimes numerically, separating stable residence, sticky transport, escape, and impact, and showing where the circumterrestrial problem is quietly secular, where it is resonantly structured, and where it becomes a broadly chaotic transport borderland. The aim is not only to merely catalog resonances and the artificial satellites and debris that inhabit or traverse them, but to recover a coherent geography of motion in the Earth–Moon system: one that clarifies long-term predictability, temporary capture, disposal pathways, and the relation between cislunar and translunar dynamics in a unified celestial-mechanical framework.

Bio. Aaron J. Rosengren is an Assistant Professor in the Jacobs School of Engineering and the Center for Astrophysics & Space Studies at the University of California San Diego. He previously served from 2017–2020 as an Assistant Professor in the College of Engineering and of the Interdisciplinary Graduate Program in Applied Mathematics at the University of Arizona. He completed his postdocs at the Aristotle University of Thessaloniki in Greece in the Department of Physics (2016–2017), as a member of the EU H2020 Project, REDSHIFT, and at the Institute of Applied Physics Nello Carrara of the Italian National Research Council (2014–2016), as a Marie Curie Fellow in the FP7 Stardust Network. He has held visiting researcher positions at UNSW Canberra in Australia, the Asher Space Research Institute at Technion in Israel, the University of Rome Tor Vergata in Italy, and the Belgrade Astronomical Observatory in Serbia. Dr. Rosengren is Fellow of the Outer Space Institute (OSI) for the sustainable development of space at the University of British Columbia and currently serves on the External Advisory Board of the Ann and H.J. Smead Department of Aerospace Engineering Sciences at the University of Colorado Boulder.