J.M. Maruskin (The San Jose State University), D.J. Scheeres (The University of Colorado at Boulder), K.T. Alfriend (Texas A&M University)
Keywords: Astrodynamics
Abstract:
When a piece of space debris is observed by optical telescopes, angular and angular-rate information can be precisely estimated from the track using basic kinematics. However range and range-rate information is to a large extent undetermined, other than by a few weak physical constraints. The standard approach in performing an orbit determination between two separate tracks of data is the least squares approach. This approach, however, presupposes a nominal estimation of the true orbit that is later corrected by the least squares algorithm. Since such an initial estimate is not known a priori for a single pass, this approach is ill-suited to deal with the increase in uncorrelated tracks expected as new telescopes come online within the next few years. The approach we describe here takes a more global perspective. After computing the admissible region, the set of all points possible belonging to a given track, for each of the two tracks, we then dynamically evolve or regress these two-dimensional regions into a common coordinate system and finally search for possible intersections. By utilizing this process,
large reductions can be made to the uncertainty in the topocentric range, range-rate space. Once candidate solutions are found a standard least squares approximation can refine the initial orbit produced by our method. This paper discusses some of the complications and advantages associated with performing these intersections.
Date of Conference: September 16-19, 2008
Track: Astrodynamics