Research Information System
Advances in Space Research, vol.77, no.10, pp.10870-10888, 2026 (SCI-Expanded, Scopus)
NGC 2168 (M35) serves as a fundamental benchmark for studying stellar evolution and dynamical environments at the transition between young and intermediate-age populations. We present a comprehensive analysis of the cluster’s kinematic, structural, and astrophysical properties utilizing high-precision astrometry and photometry data from Gaia Data Release 3 (DR3), complemented by 2MASS data. A statistical membership assessment yields a clean sample of probable members (N (Formula presented) 1397), with mean proper motion components of (Formula presented) and (Formula presented), along with a mean trigonometric parallax of (Formula presented). We derived the cluster’s fundamental parameters via isochrone fitting, determining an age of (Formula presented), a metallicity of (Formula presented), and a probabilistic distance of (Formula presented). The radial density profile is well described by a generalized King model with (Formula presented) ((Formula presented) ), revealing the presence of a loosely bound, extended stellar halo. Furthermore, we detect a spatial elongation oriented perpendicular to the Galactic plane, likely a signature of vertical tidal heating or disk shocking. The mass function analysis exhibits a multimodal Gaussian structure, suggesting a complex dynamical formation history beyond a simple power-law distribution. Finally, orbital integration confirms NGC 2168 as a thin disk object with a maximum vertical excursion of (Formula presented), consistent with the observed vertical morphological deformation.