One of four stars that make the Xefroni stellar group. The Potemkin visited Xefroni B while following the anti-proton trail left by the Planet Killer. The ship had already found a destroyed planet in the Xefroni A system, and found a concentration of anti-protons in Xefroni B. However, there were no destroyed planets and the ship moved on to the "Abbott and Costello" system where more anti-protons were detected.