Crown of Thorns
The Crown of Thorns is a deep space asteroid field ringing Crucible's sun. Many colonies and mining structures exist throughout the field despite life being hard and perilous. Penal colonies often work the most dangerous asteroids although tehere are a few wild-catters or Black Colonies (formed without Imperium influence).
Aside from the penal colonies, the Crown of Thorns is largely lawless but for a few roving Arbites (sometimes called Marshalls), who struggle to maintain the law.