Seeing Stars: Learned Star Localization for Narrow-Field Astrometry

Abstract

Star localization in astronomical imagery is a computer vision task that underpins satellite tracking. Astronomical star extraction techniques often struggle to detect stars when applied to satellite tracking imagery due to the narrower fields of view and rate track observational modes of satellite tracking telescopes. We present a large dataset of real narrow-field rate-tracked imagery with ground truth stars, created using a combination of existing star detection techniques, an astrometric engine, and a star catalog. We train three state of the art object detection, instance segmentation, and line segment detection models on this dataset and evaluate them with object-wise, pixel-wise, and astrometric metrics. Our proposed approaches require no metadata; when paired with a lost-in-space astrometric engine, they find astrometric fits based solely on uncorrected image pixels. Experimental results on real data indicate the effectiveness of learned star detection: we report astrometric fit rates over double that of classical star detection algorithms, improved dim star recall, and comparable star localization residuals.