An asteroid belt exists in SR388's solar system. It is clearly visible from Biologic Space Laboratories research station, which is in orbit around the planet. This asteroid belt claimed Samus Aran's Gunship, when she accidentally flew the ship into the belt due to disorientation caused by her X Parasite infection. The ship launched an escape pod, saving her life for the time being. The belt is mentioned in the gunship's trophy description in Super Smash Bros. Brawl.
Ceres Space Colony is also said to have an asteroid belt nearby, RX 338 is depicted being surrounded by a belt and the solar system on the Celestial clock also seems to have a belt at its fringe. In Metroid Prime, FS-176 is seen to have an asteroid belt around it.