Cerebus Prime is an inhabited planet located in the Cerebus star system, in or near Federation space in the Alpha or Beta Quadrant. This world is home to the Hiinkan species. At some point in the 23rd century, a plague broke out among the local population. Starfleet responded to the crisis by sending a large medical team, which included Dr. Mark Piper, to the planet to see if they could find a cure. Eventually, Piper succeeded in curing the plague, and he was given a latinum honor medallion in recognition of his efforts. By 2265, the planet also contained three medical facilities that were named after Piper. (TOS - My Brother's Keeper novel: Constitution)