In 2020 a team led by European Southern Observatory (ESO) astronomers reported the closest black hole to Earth, located just 1000 light-years away in the HR 6819 system. But based on the latest observations there is in fact no black hole in HR 6819, which is instead a two-star system with mass transfer in a rare and short-lived stage of its evolution.
This research was presented in the paper “HR 6819 is a binary system with no black hole: Revisiting the source with infrared interferometry and optical integral field spectroscopy”, Frost A. J. et al. (DOI: 10.1051/0004-6361/202143004) to appear in Astronomy & Astrophysics. Mauricio Cabezas, one of the co-authors of this paper, PhD student at Charles University, Prague, was working on this publication at the Astronomical Institute’s Department of Galaxies and Planetary Systems and is currently member of the Stellar department.