We present the stellar population , using Gaia DR2 parallax , kinematics , and photometry , of the young ( \sim 100 Myr ) , nearby ( \sim 230 pc ) open cluster , Blanco 1 .
A total of 644 member candidates are identified via the unsupervised machine learning method StarGO to find the clustering in the 5-dimensional position and proper motion parameter ( X , Y , Z , \mu _ { \alpha } \cos \delta , \mu _ { \delta } ) space .
Within the tidal radius of 10.0 \pm 0.3 pc , there are 488 member candidates , 3 times more than those outside .
A leading tail and a trailing tail , each of 50–60 pc in the Galactic plane , are found for the first time for this cluster , with stars further from the cluster center streaming away faster , manifest stellar stripping .
Blanco 1 has a total detected mass of 285 \pm 32 M _ { \sun } with a mass function consistent with a slope of \alpha = 1.35 \pm 0.2 in the sense of dN / dm \propto m ^ { - \alpha } , in the mass range of 0.25–2.51 M _ { \sun } , where N is the number of members and m is stellar mass .
A Minimum Spanning Tree ( \Lambda _ { MSR } ) analysis shows the cluster to be moderately mass segregated among the most massive members ( \ga 1.4 M _ { \sun } ) , suggesting an early stage of dynamical disintegration .