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