The Extended Tidal Tails of NGC 7089 (M2)

Using photometry and proper motions from Gaia Early Data Release 3, we detect a 45 degree-long trailing stellar debris stream associated with the old, metal-poor globular cluster NGC 7089. With width on order of 100 pc, extended appears to be as dynamically cold coldest known streams found date. There is some evidence for an leading tail extending between 28 37 degrees cluster, though greater distance this tail, combined that are virtually indistinguishable those foreground stars, make detection much less certain. The motion profile path sky not well matched using simple Galactic potential comprised purely disk, bulge, spherical halo. However, addition moving, massive (M = 1.88 x 10^(11) solar masses) Large Magellanic Cloud brings model predictions into better agreement observables. We provide tables most highly ranked candidate stars follow-up by ongoing future spectroscopic surveys.