This could explain the differences between the black holes at the centre of active galaxies (like Cygnus A) and their less active cousins (like our own Milky Way): the presence or absence of a ...

While considered a mathematical possibility for many years, the first black hole wasn’t discovered until Cygnus X-1 in 1971. We now know that black holes occur frequently throughout the universe.

AT 2021hdr occurs in a galaxy located a billion light-years away in the constellation Cygnus ... binary black holes interact with their surroundings. Hernández-García’s team plans to continue ...