SPH hydrodynamical simulation of a binary black hole system after a galactic merger.
SPH hydrodynamical simulation showing how a binary black hole forms in the aftermath of a galactic meger. Depicted are the galactic discs of two interacting galaxies. When the merger is completed a close Keplerian binary comprising the two massive black holes forms at the center of a massive circum-nuclear disc (credit by L. Mayer et al., Science, 316, 1874, 2007).
Credit: L. Mayer et al., Science, 316, 1874, 2007