From publisher blurb: Cepheus Engine and the Original Science Fiction Roleplaying Game lets Referees quickly and easily create entire worlds using the Universal Planetary Profile. Maps can expand the desciption the UPP gives, but while tools exist to help the Referee create maps for habitable worlds, these tools fail when it comes to mapping lifeless vacuum planets. The general view seems to be that such planets are boring hunks of rock. It doesn’t have to be this way. Real-life vacuum worlds such as our Moon, the planet Mercury, and many of the gas giant satellites show that such bodies can have interesting, even surprising terrain. Mapping Vacuum Worlds is meant to give the Referee a way to create that terrain. In it, Referees will find a concise yet detailed process for fleshing out a vacuum world with the sort of terrain that makes for good astronomical observations or gripping planetside adventures. In just a few die throws, a barren hunk of rock only good for supplying a background can instead become a memorable part of the story. Mapping Vacuum Worlds. Mind the gap(s).