Satellite Collision Probability Enhancements

This work refines collision probability calculations for rectangular object shapes of unknown orientation and compares those results to their representations as spheres. Conjunction probability analysis for spherical objects exhibiting near-linear relative motion is accomplished by combining covariances and physical object dimensions at the point of closest approach. The resulting covariance ellipsoid and hardbody can then be projected onto the plane perpendicular to relative velocity. Collision potential is determined from the object’s physical footprint on the projected, two-dimensional, probability density space. In the absence of object attitude information, a footprint that completely defines the region where the two objects might touch must be created. This footprint can then be rotated to determine the orientation that produces the largest probability making it the most conservative estimate for the given conjunction conditions. A further enhancement is presented to address the maximum possible probability for a given miss distance while also assessing the sufficiency of the orbital data to meaningfully support the calculations.