This study introduces a new "Non-Dimensional" star identification algorithm
to reliably identify the stars observed by a wide field-of-view star tracker
when the focal length and optical axis offset values are known with poor
accuracy. This algorithm is particularly suited to complement nominal
lost-in-space algorithms, which may identify stars incorrectly when the focal
length and/or optical axis offset deviate from their nominal operational
ranges. These deviations may be caused, for example, by launch vibrations or
thermal variations in orbit. The algorithm performance is compared in terms of
accuracy, speed, and robustness to the Pyramid algorithm. These comparisons
highlight the clear advantages that a combined approach of these methodologies
provides.Comment: 17 pages, 10 figures, 4 table