Modeling and Characterization of Structural, Thermophysical, and Dynamical Evolutions of Small Bodies in the Solar System

Explorations of small bodies in the solar system––such as asteroids and comets––offer unique opportunities to study the remnants of the early solar system. These small bodies often challenge our expectations, revealing surprising findings that raise questions about planetary formation, evolution, and even the origins of life. The field of planetary science seeks to address these questions through interdisciplinary approaches, combining insights from astronomy, geology, chemistry, physics, and engineering to better understand the story of our solar system. This dissertation concerns the evolution of near-Earth asteroids, focusing on their structural, thermophysical, and dynamical evolutions to provide a more comprehensive view of their life cycle. Asteroids exhibit a remarkable diversity of shapes, reflecting their complex evolutionary pathways. This dissertation begins by exploring their structural condition through the development of a semi-analytical model based on granular physics, offering rapid yet accurate insights into asteroid reshaping and mass-loss processes. Second, a 3-dimensional thermophysical model is developed to better characterize the thermal conditions of asteroids, a key factor giving rise to non-gravitational perturbations on their dynamics. Finally, the work extends to binary asteroid systems, coupling detailed shape models with full two-body gravitational dynamics and thermal torque modeling to quantify the effects of both impact-induced reshaping and the binary-YORP effect. Collectively, these studies provide a more integrated understanding of the physical processes governing small body evolution, with direct applications to planetary defense mission such as NASA’s DART and ESA’s Hera.

Level thesis:degree_level

Doctoral

Department dc:contributor.department

Aerospace Engineering

Grantor dc:publisher

Georgia Institute of Technology

Year dc:date.issued

2025

Author dc:creator

• Nakano, Ryota

Advisor dc:contributor.advisor

• Hirabayashi, Masatoshi

Committee members dc:contributor.committeemember

• Carr, Christopher E
• Li, Gongjie
• Wray, James J
• Richardson, Derek C

• Asteroid formation
• Asteroid evolution
• Orbital dynamics
• Rotational dynamics
• Structural analysis
• Thermophysical analysis
• Planetary defense

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/1853/80152

OAI identifier oai:identifier

oai:repository.gatech.edu:1853/80152