Hades IV was a planet, most likely destroyed by the hadesians itself. The planet is broken in two distinct halves and still classified as a 'regular' planet, because it has not degenerated into an asteroid field.
"Hades’ famous “half planet”. This world was split in two distinct halves by a mysterious force."
|Location||Orbits Hades (star)|
Hades IV is commonly considered a ‘half planet,’ leading to the somewhat confusing ‘3.5 worlds’ listing in the formal UEE listing. While the entire planet still exists (and has not degenerated into a complete asteroid field) it does so in two distinct halves. It’s impossible to wholly comprehend the absolute horror of a weapon capable of destroying an entire planet, but it is difficult not to marvel at the spectacle of this desolation. 
Despite the illegality of attempting, various weapons corporations are very interested in hiring well funded outfits to try to get in and see what the supposed tech on Hades IV might be and whether it can be replicated and sold. 
This asteroid cluster is the result of the devastating event that befell Hades IV.
|Locations in the Hades System|