2025RNAAS...9..346Q

We present a test of the symmetry of tidal tails in nearby open clusters (OCs) within 1 kpc using Gaia Data Release 3. We fit King density profiles to obtain the tidal radius for each OC and identify leading and trailing tail members according to their projected direction along the cluster orbit. For most OCs, the leading and trailing tidal tails contain comparable numbers of stars. Our results provide strong observational evidence (at the 15σ-level) against the Milgromian dynamics prediction of asymmetric tidal tails and reinforce the conventional Newtonian understanding of tidal escape in OCs.