Black Hole Classification

Black holes are classified by their mass in solar masses, expressed as an exponential. The black hole at the center of the Milky Way Galaxy is approximately 4.3 million solar masses, making it a Class 6 black hole. Black hole size is important in calculations for gravity drive travel, with larger concentrations of mass at both ends of a jump allowing for greater total jump distance. Thus, a galaxy like the Andromeda Galaxy or the Sombrero Galaxy, which houses a larger central black hole than the Milky Way, can be used as a point of departure or arrival for longer trips through intergalactic space than one could make to or from the Milky Way. The most massive black hole in the Laniakea Supercluster is thought to be in The Castle, but its precise whereabouts are only known to high-level operatives in the King's government. The second-largest black hole in Laniakea is the black hole in the center of the King's Galaxy, with an approximate mass of 6.3 billion solar masses, making it a Class 9 black hole (with a precise rating of 9.799). The King's Galaxy is also the largest, most massive galaxy in the Virgo Cluster, the first major group of galaxies where human civilization expanded.

The theoretical maximum size that a black hole can naturally reach is 50 billion solar masses, though the largest observed is only 43 million solar masses, lying some 8.8 Gpc away from Laniakea, well beyond the current reach of human civilization. A second, with 40 million solar masses, lies 3.7 Gpc away from Laniakea, but is still far beyond the Kingdom of Mankind.