Accession Number : ADA289321

Title :   Tracking and Impact Prediction of Earth-Crossing-Objects (ECOs) on a Collision Course with Earth.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Bishop, Gregory A.

PDF Url : ADA289321

Report Date : DEC 1994

Pagination or Media Count : 108

Abstract : This study investigated the effectiveness of Earth-based angles only observations in determining the orbit of various hypothetical Earth-Crossing-Objects (ECOs). 'True' trajectories were simulated specifically for Earth-Crossing- Comets (ECCs) by numerically integrating in a Restricted Three Body system. Starting at Earth impact points, the state vectors were reverse-propagated" to a proposed detection time. Observations (obs), with state-of-the-art accuracy, were then simulated with error induced by a Gaussian random number generator; these were used in a least- squares differential corrector to estimate the positions of the ECOs. State vectors and covariance matrices were then propagated to the impact times and axis lengths of the one sigma impact footprint were calculated. Varied amounts of data were fed into the differential corrector and it was determined that Earth-based obs alone may be ineffective in predicting an ECC's orbit.

Descriptors :   *CELESTIAL MECHANICS, *COMETS, *ASTEROIDS, COMPUTERIZED SIMULATION, ANGLES, GROUND LEVEL, EQUATIONS OF MOTION, OPTICAL DETECTION, EARTH ORBITS, STATE OF THE ART, MATRICES(MATHEMATICS), OBSERVATION, RADAR TRACKING, ACCURACY, THESES, COVARIANCE, IMPACT PREDICTION, COLLISIONS, N BODY PROBLEM, IMPACT POINT, INTERPLANETARY TRAJECTORIES.

Subject Categories : Celestial Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE