If you think your life is busy, imagine the life of Mrk 533.
This active galaxy is the largest and brightest member of its group, and its tidal tails are testament to its busy social life — interactions with its companions are literally tearing the galaxy in all directions.
One of those interactions may have come a little too close. New observations reported in Nature Astronomy reveal a double radio source at the center of Mrk 533, possibly the emission from a close pair of supermassive black holes separated by only a light-year in their orbits. The closest pair known until now, discovered in the galaxy 0402+379, orbits 24 light-years apart.
Gravitational swipes from smaller galaxies are probably responsible for the gas that’s spiraling down to feed the putative pair of black hole beasts at the heart of Mrk 533. Even though we view the galaxy face on, observations show that we see the central black hole(s) equator-on, and a thick veil of dust and gas hides much of the emission. Preeti Kharb (National Centre for Radio Astrophysics, India) and colleagues used the Very Long Baseline Interferometer (VLBI) to peer through this veil and into Mrk 533’s core. Probing various radio frequencies, the team found that the single source of radio emission resolved into two sources at 15 GHz.