The Moon pirates

The Moon was the first escape destination once the Earth was doomed, but the unorganised waves of migration soon brought with them the Athanor, and the moon colonies panic, isolate themselves from each other collapse, scavenge each other's corpses, and, when the Exodus projects fly them by, some of the scared moon colonies decide to highjack them.

The first attempt is a huge success and a colony escapes the moon on an Earth ship that has been taken over.

All colonies start a mad scramble for other Exodus projects, while these ones, now ready, defend themselves with heavy weaponry, dousing the surface in nuclear blasts that renders the survivors even more rabidly eager to escape this hellish rock.

The moon pirates are now fairly elusive and silent, the surface gone cold, but many suspect them of having organised under the surface for assaults from the dark side of the moon. So any new Exodus project will always carry some nuclear torpedoes just in case and, if they can fly by unchallenged, will still throw these torpedoes blindly to the moon surface as a sort of "burning bridges" tradition and in the hope of destroying some of the remaining pirates.