Analysis of Close Stellar Encounters with the Solar System
  We consider 36 candidates for close (within 1 pc) encounters with the Solar
system. These stars have been selected in accordance with the results of an
analysis of their motion obtained by various authors. For most stars from this
list the kinematic characteristics have been taken from the Gaia DR2 catalogue.
The parameters of the encounters of these stars with the Solar system have been
calculated using three methods: (1) the linear one, (2) the epicyclic one, and
(3) by integrating the orbits in an axisymmetric potential. We have concluded
that the epicyclic method works quite well only on a time interval no longer
than $\pm$1 Myr. Based on the third method, in good agreement with the first
method, for the first time we have obtained the following estimates of the
encounter parameters for the star Gaia DR2 3130033734235815424:
$t_{min}=-0.62\pm0.12$ Myr and $d_{min}=0.30\pm0.10$ pc.
