Stellar flyby refers to the close passage of two or more stars, which remain unbound after their passage The Sun resides in a region of relatively low stellar density in the Milky Way.
Thus, close stellar flybys are relatively rare.
One example is Scholz's star (WISE designation WISE 0720−0846 or fully WISE J072003.20−084651.2), which is a dim binary stellar system 22 light-years (6.8 parsecs) from the Sun in the constellation Monoceros near the galactic plane.
[1] Gliese 710 or HIP 89825, an orange 0.6 M☉ star in the constellation Serpens Cauda, is projected to pass near the Sun in about 1.29 million years at a predicted minimum distance of 0.051 parsecs—0.1663 light-years (10,520 astronomical units) (about 1.60 trillion km) – about 1/25th of the current distance to Proxima Centauri.
In young clusters, such close stellar flybys might influence the frequency and size of protoplanetary discs,[2] and influence the planet formation process in these environments.