Dylan R. Penn, Virginia Polytechnic Institute and State University; Cameron Harris, Virginia Polytechnic Institute and State University; Kevin Schroeder, Virginia Polytechnic Institute and State University; Jonathan Black, Virginia Polytechnic Institute and State University
Keywords: noncooperative maneuver, closely space objects, maneuver detection
Abstract:
Maintaining knowledge of the current and future locations of resident space objects (RSOs) is a critical focus of space traffic management (STM). This paper seeks to identify regions of an orbital pass over a ground-based sensor that are conducive to the detection of orbital trajectory changes. The ideal observation would be that made at the point when apparent angular separation from the expected trajectory is maximized. A ground site overflight model was built to characterize the apparent separation between an expected and perturbed trajectory of the satellite. The geometry of an overflight was parameterized in terms of rise point and relative heading. An algorithm was developed to define initial conditions of the satellites which span all possible pass geometries. Given a positive-velocity maneuver, trajectories which progress nearly-directly overhead of a ground site experience a “catch-up” effect, where the lower trajectory catches up and overtakes the higher orbit. The catch-up effect can be characterized, given a selected maximum angular separation, by a convex region in azimuth-elevation space. Angular separation is maximized when viewed during the middle portion of the pass, whereas range separation is maximized at the end of a pass. Changes in altitude or maneuver magnitude do not meaningfully impact the trends of angular or range separation in time or space.
Date of Conference: September 27-20, 2022
Track: Astrodynamics