Stellar Occultation Observations of (38628) Huya and Its Satellite: A Detailed Look into the System

The physical and orbital parameters of trans-Neptunian objects provide valuable information about the solar system’s formation and evolution. In particular, the characterization of binaries provides insights into the formation mechanisms that may be playing a role at such large distances from the Sun. Studies show two distinct populations, and (38628) Huya occupies an intermediate position between the unequal-sized binaries and those with components of roughly equal sizes. In this work, we predicted and observed three stellar occultation events by Huya. Huya and its satellitewere detected during occultations in 2021 March and again in 2023 June. Additionally, an attempt to detect Huya in 2023 February resulted in an additional single-chord detection of the secondary. A spherical body with a minimum diameter of D = 165 km can explain the three single-chord observations and provide a lower limit for the satellite size. The astrometry of Huya’s system, as derived from the occultations and...