Now updated for GURPS Fourth Edition, this is the ultimate toolkit for any campaign between the stars. Explore options for space travel and technology, from the realistic to the miraculous. Design alien races and monsters. Create campaigns of every style, from science fantasy to space opera to star merchants. Build worlds, from asteroids to Dyson spheres. With this book, you can create anything from a single alien beast to a whole galaxy of civilizations and star systems... quickly and randomly, or with a detailed step-by-step process that's true to biology and astrophysics as we understand them today.
GURPS Space has two things going for it. The first is the best (or at least closest to scientifically plausible) random world and star system generation rules on the market (although the hardcover has a glitch in the lunar tidal force equation which is corrected in the PDF). The second is a alien generation system which is an update of the fascinating system used in GURPS Uplift.
Fantastic source manual for creating speculative fiction settings for gaming or story-telling. The text adequately reduces to understandable models a number of key astrophysics elements defining our current understanding of stellar mechanics, while also suggesting copious ideas drawn from exemplary fiction on how to set stories in such locales.
This is my go to book when it comes to star system generation. By far the best Sci-Fi world building system I came across, so far, for pen and paper RPGs, anyway. It's a bit time consuming if you do it on paper, but at the end of the process you have a scientifically sound star system and you might even learn a bit of basic astronomy along the way.
This book laid the foundation for the world I first brought to life as a role-playing game—and later transformed into my novel, [Echoes of the Final Battle](https://www.goodreads.com/book/show/2...).