2019MNRAS.484L.114K

NGC 288 is a Galactic globular cluster having observed extra-tidal structure, without confirmed tidal tails. Gaia DR2 provides photometric and astrometric data for many of the stars in NGC 288 and its extra-tidal structure. To compare with the Gaia data, we simulate a N-body model of a star cluster with the same orbit as NGC 288 in a Milky Way potential. The simulation shows that the cluster forms tidal tails that are compressed along the cluster's orbit when it is at apocentre and are expected to be a diffuse bipolar structure. In this letter, we present a comparison between the simulation and observations from Gaia DR2. We find that both the simulation and the observations share comparable trends in the position on the sky and proper motions of the extra-tidal stars, supporting the presence of tidal tails around NGC 288.