Department of Aerospace Engineering

Guidance, Control, and Astrodynamics Seminar: Brian Kaplinger: "Orbital Dispersion Simulation of Near-Earth Object Deflection/Fragmentation by Nuclear Explosions"

Brian Kaplinger

Brian Kaplinger

AER E Graduate Student (Bong Wie, Major Professor)

Thursday, October 1, 2009
4:10 PM
Room 1235 Howe Hall

ORBITAL DISPERSION SIMULATION OF NEAR-EARTH OBJECT DEFLECTION/FRAGMENTATION BY NUCLEAR EXPLOSIONS

Attempts to deflect Near-Earth Objects (NEOs) from an impact trajectory can plausibly fragment the NEO rather than deflect it.  High energy methods proposed for NEO deflection, such as nuclear explosions, are designed to ablate surface material, and therefore are close to the energy threshold needed to fragment the NEO.  This paper addresses the orbital dispersion of a fragmented NEO using Apophis as a model, and presents a physical description of the relative motion phenomena needed to describe such a system.  The overall stochastic model is approximated using a deterministic random process in which the randomness of fragmentation is associated only with the initial condition.  Categories of initial probability distributions are analyzed to obtain relationships between initial conditions and eventual percentage of impacting bodies.  A Direct Simulation Monte Carlo approach is taken to resolve sample cases using a relative motion algorithm to confirm previous results.  Consequences of ignoring mutual gravitation of the fragmented system or relying on linearized models for large time scales are discussed. This project has resulted in one of the largest sets of raw data for NEO fragmentation in the deflection community, opening the way for future work considering the minimization of fragmented body impacts. 

Bio:  Brian Kaplinger received his BS in Aerospace Engineering from Iowa State in 2009.  He has received scholarships and awards for research from Iowa State University, NASA, and the Universities Space Research Association.  Currently, Brian is pursuing a Ph.D. in Aerospace Engineering under Prof. Bong Wie.  His research interests include Astrodynamics, Optimization, Applied Mathematics, and Computational Algorithms.