If you want to inject more raw science into your SF worldbuilding, go get a copy of GURPS Space (4e) today! Just reading it is like getting a college degree in astrophysics. Keep in mind, it is not perfect–but it will help you out tremendously.
Not a Full SF Rulebook, But A Toolkit
I first picked up GURPS Space as I was starting to flesh out worlds for Full Thrust. I was pretty amazed. It is not a full book for SF roleplaying–there are parts that are not included in the fourth edition that are needed for that. (Those include rules for things like spaceships and equipment).
What the book does provide, though, is a toolkit for building the game and setting that you want. The first section goes into depth about SF genres and tropes. It helps GMs come up with the right game that they and their players want–hard science, space opera or something in between.
The second section is dedicated to worldbuilding, and it is awesome. It goes into great depth about constructing a SF setting, from mapping the stars, to detailing the star systems–stars, planets and other objects.
It really shines in using real science, distilled to game mechanics, to create realistic planets or moons. This includes down to the physical characteristics of a body, such as diameter, mass and gravity, to other characteristics like tectonic and volcanic levels. All of this has some math, but nothing that cannot be managed.
The third section is all about alien creation, again based on real science. It goes into a lot of detail about biology and psychology, helping GMs come up with alien life forms that make sense, and not rubber-suited man-like creatures.
The last section presents a number of concepts and ideas about SF societies, and how to incorporate them into the game.
It Still Needs More Info
OK, if it is so great, what else does it need? For starters, it needs some information on weather. This includes how it works, and how to flesh out the weather planets on various planetary types.
The other thing that it needs more information on is economics. That is a very complex subject, but the information in GURPS Space just whets the appetite for more. What is needed are simple, concise rules for establishing a basic economic structure for the setting. This is something that could be used as a backdrop for any campaign.
Yet one more thing that could be beefed up are the rules on alien vegetation. The book goes into detail about animal and intelligent life forms, but the rules for alien plant life are pretty sketchy. In particular, guidelines on how to build up the various plant life on worlds with different conditions, from stars to atmospheres.
The Tricky Part With Space Science
The problem with any source book that deals with astronomy or astrophysics is that they become dated–fast. Science is learning so much about exoplanets and astronomy, so fast, that it is impossible to keep up with the new discoveries. You just have to pick a point and go from there.
Still, GURPS Space is a great place to start. I doubt that Steve Jackson Games will update it anytime soon, but it is well worth the money as it is. You can pick up a PDF copy at sjgames.com or at DriveThruRPG.com. Do it–you will not be disappointed!
Marko ∞
(Originally published on farjewel.com, on 4/1/2018.)
