We present a new approach to the pointing determination of Imaging
Atmospheric Cherenkov Telescopes (IACTs). This method is universal and can be
applied to any IACT with minor modifications. It uses the trajectories of the
stars in the field of view of the IACT's main camera and requires neither
dedicated auxiliary hardware nor a specific data taking mode. The method
consists of two parts: firstly, we reconstruct individual star positions as a
function of time, taking into account the point spread function of the
telescope; secondly, we perform a simultaneous fit of all reconstructed star
trajectories using the orthogonal distance regression method. The method does
not assume any particular star trajectories, does not require a long
integration time, and can be applied to any IACT observation mode. The
performance of the method is assessed with commissioning data of the
Large-Sized Telescope prototype (LST-1), showing the method's stability and
remarkable pointing performance of the LST-1 telescope.Comment: Presented at the 38th International Cosmic Ray Conference (ICRC
2023), 2023 (arXiv:2309.08219