Black Hole, White Dwarf Star In Closest Known Binary System With Smallest Orbit In Milky Way

A binary system in the globular cluster 47 Tucanae — about 14,800 light-years away from Earth but inside the Milky Way — has been known for years, but it was only in 2015 that astronomers found one of the stellar bodies was a black hole. And using new observations, scientists now think the other star is a white dwarf that orbits its companion at the closest distance to a black hole ever observed in our galaxy.