Extended Tidal Tails of IC 4756 Detected by Gaia EDR3

We report the discovery of emerged tidal tails around open cluster IC 4756 ($\sim$ 1 Gyr) based on 644 members identified from {\it Gaia} EDR3. Three-dimensional spatial positions, two-dimensional tangential velocities $\left( x, y, z, \kappa \cdot \mu_{\alpha}^{*}/\varpi, \mu_{\delta}/\varpi \right)$ are utilized to determine co-moving member candidates 4756. Using a Bayesian method, we correct distance for each member. Two extend up 180 pc and display S-shape in $X^{\prime}Y^{\prime}$ space (Cartesian coordinates focused center). A clean sequence our Color-Absolute-Magnitude Diagram (CAMD) indicates coeval population matches perfectly with PARSEC isochrone age Bossini et al. (2019). Mass segregation is detected this as well. Finally, derive radius core about $12.13$ $4.33 \pm 0.75$ pc, respectively.