Orbital perturbation analysis of earth-crossing asteroids
Knudson, Wade E.
MetadataShow full item record
Earth Crossing Asteroids (ECAs) are those asteroids whose orbit cross section can intersect the capture cross section of the Earth as a result of secular gravitational perturbations. This thesis provides a framework for understanding the origin, nature, and types of ECAs. The change in velocity requirements to achieve a two Earth radii deflection for long and short term warning scenarios are developed. Next, a method of developing hypothetical Earth colliding asteroid orbits is presented. These hypothetical orbits are used in two ways: (1) to evaluate the ability of Dance of the Planets, a solar system simulation model developed by Applied Research and Consulting, Inc., to accurately propagate orbits of imported asteroid orbits, and (2) to analyze the sensitivity of deflection distance to variation in deflection angle and orbital parameters of a given orbit. Inaccuracies during importation of data precluded the use of Dance of the Planets for the purpose of sensitivity analysis. The program does provide an excellent tool for visualization of ECA scenarios. Consequently, a simpler orbital model was developed to provide a Earth miss distance sensitivity analysis. With one asteroid orbital period warning the minimum change in velocity to deflect an asteroid two Earth radii is approximately 0.135 m/s and the optimal deflection is along the flight path. Maximum deflection occurs when the deflection is applied at perihelion. The miss distance decreases markedly with increase in true anomaly until it is a minimum at aphelion.
Showing items related by title, author, creator and subject.
Duncan, Robert C. (Cambridge, Massachusetts; Massachusetts Institute of Technology, 1960-01);Entry of astronautical vehicles into planetary atmospheres is examined in this thesis with respect to interactions of the guidance function, vehicle performance, trajectory prediction, and mission objectives. All entry ...
Dumas, James Walter (Cambridge, Massachusetts; Massachusetts Institute of Technology, 1970-05);A program was undertaken to investigate the dynamic response of cylindrical shell panels to impulsive loads. Hot--rolled mild steel and aluminum 6061-T6 panels of various thicknesses and two panel sector sizes were loaded ...
Hiriart Le-Bert, Gerardo (Monterey, California. Naval Postgraduate School, 1973-12);A class of analytical and numerical solutions to the problem of inviscid-jet deflection from plane and axisymmetric concave surfaces are presented. The methods of solution for the two-dimensional cases included a novel ...