Abstract
The uncertainty region associated with short arcs is typically large, making the initialization of orbit estimators a challenging task. In this work we propose a method to reduce the size of the uncertainty region using automatic domain pruning. The initial orbit and its confidence region are obtained by using a differential algebra-based initial orbit determination algorithm and a least squares algorithm. New measurements are used to reduce the size of the confidence region by retaining only those portions of the domain in which the likelihood is above a certain threshold.