This is the Revyia Asteroid Field. The asteroid of the Revyia system is quite a sight for anyone to see. One could assume that it might have been a cloud of leftover galactic dust from the formation of this system, or they could have one of many other possible origins.
The asteroids in this belt surround the planets in this system like a veil of protection, making trips to and from the planets quite dangerous. But this also serves as a very useful defensive aid. People wishing to attack the Black Sun would have to bring fleets of ships across this belt of asteroids, which would indeed be a perilous journey.
Historians record that an asteroid once crashed into the only moon in this system. This caused a catastrophic event that created major environmental problems on the moon for a short period of time. This followed a nearly month-long blackout after the asteroid impacted on the surface.