Gaia18ajz is a candidate black hole that was discovered through a microlensing event. Its mass and distance is not exactly known but it can either be located 1.14 kiloparsecs from earth with a mass of 4.9 solar masses or located at a distance of 1.31 kiloparsecs from earth with a mass of 11.1 solar masses. It was discovered in 2018 by the Gaia Science Alerts system through gravitational microlensing.
References