Stars Outside the Hipparcos List Closely Encountering the Solar System

TL;DR

This study identifies stars outside the Hipparcos list that have closely encountered or will encounter the Solar System, including two new candidate stars and potential risks to the Oort cloud.

Contribution

First identification of stars outside the Hipparcos catalog that have closely approached or will approach the Solar System, with new candidate stars and encounter probability estimates.

Findings

GJ 3379 may have encountered the Sun within 1.32 parsecs 163,000 years ago.

Two potential encounter candidates have only photometric distance data.

Encounter probabilities for some stars are estimated at 0.09 and 0.05.

Abstract

Based on currently available kinematic data, we have searched for stars outside the Hipparcos list that either closely encountered in the past or will encounter in the future the Solar system within several parsecs. For the first time, we have identified two single stars, GJ 3379 (G 099-049) and GJ 3323 (LHS 1723), as candidate for a close encounter with the solar orbit. The star GJ 3379 could encounter the Sun more closely to a minimum distance d_min=1.32+\-0.03 pc at time t_min=-163+\-3 thousand years. We have found two potential candidates for a close encounter that have only photometrical distances: the white dwarf SSSPM J1549-3544 without any data on its radial velocity and the L-dwarf SDSS J1416+1348. The probabilities of their penetration into the Oort cloud region are 0.09 (at a model radial velocity |V_r| = 50 km/s) and 0.05, respectively.