Holm 15A* size and scale context

Holm 15A* is the ultramassive black hole in the central galaxy of the Abell 85 galaxy cluster, measured at about 40 billion solar masses. That makes its event horizon enormous, while Holm 15A’s unusually diffuse center preserves evidence of the mergers that helped build it. Read its scale context, comparisons, and journey links on the canonical object page.