Designer's Notes: Transhuman Space: In The Well
by Jonathan Woodward
Oh give me a home
Where the asteroids roam
And the gleebs and the buzzy mugs play
Where gravity's low
And the water is snow
And the desert winds blow you away
Mars, Mars is my home
Where everyone's short just like me
I wish I was where
There is not so much air
And two moons to shine down upon me.
There's a lot lurking beneath the surface of Mars. Water. Valuable ores. And, it seems, a lot of number crunching.
Redrawing The Map
The voice boomed down from the loudspeakers in the bottom of the hopper. "Sir, you only have a few minutes. If you don't let me land and take you on board, you'll die."
"Take your lies, and your noisy engines, straight to Charon. I'm working a vein of ore here, and I'm sick of these tricks. There hasn't been water here in a billion years." The prospector's furry fist gestured obscenely, and he went back into his hut.
An amplified sigh echoed against the canyon wall. "Fine. Have it your way." The hopper lifted into the sky, and headed for the top of the cliff; too much distance wasn't enough, in the pilot's opinion.
The prospector came back out as it left, to make sure it did. Claim-jackers are getting weirder every year. Smart, though. Didn't think I'd be found this deep in a side canyon. Better go into town and get more ammo, in case he comes back. The prospector hadn't been into town in months, or he'd know it had been evacuated. As he turned to make sure his trike was functional, he heard a noise from the main canyon. Then the ground began to rumble. The noise grew louder, until it shook the world. He clapped his hands over his ears, but it still became too loud to bear. He lost his footing, and fell. He gazed in horror as a 10-story wave crashed into the fork where his canyon joined Marineris. In seconds, it was upon him.
Where the hell did that claim-jacker get all this water? was his last thought.
* * *
In The Well includes the new System Object Record Sheet, based on the Planetary Record Sheet from GURPS Space. The Transhuman Space universe requires different information from a generic Space campaign, so the new sheets leave off some entries from the old PRS, and add new ones. It still includes the equal-area icosahedral map, however. Unlike most uses of this map, for In The Well I had to depict real worlds for which detailed maps already exist: Mars, Venus, and Mercury. The issue of how to make sure geographic features were placed correctly was a serious one.
Fortunately, a little trigonometry provided the answers. The prime meridan -- the dotted line running from north pole to south pole -- runs from the tip to the middle of the base of two triangles, and across one side of a third. 180° = h + h + h/cos(30°), ergo when measuring north-south, each triangle is 57.06° from base to tip, or 65.88° along its side. Thus, the triangle vertices (excluding the poles) are at (90 - 65.88)°, or 24.12°, north or south. Note that the lines connecting these vertices are not parallels (i.e., latitude lines). Each triangle-edge is part of a great circle -- a circle with its center at the center of the planet. Lines of latitude aren't great circles. Though the ends of each apparently east-west edge are at 24.12° north or south, the middles of these edges are at 32.94° north or south.
For longitude, it was only necessary to divide 360° by 10. There are 10 "equatorial" triangles. If you draw a vertical line through the middle of each, they are at 0°, 36°, 72°, 108°, 144°, 180°, 216°, 252°, 288°, and 324° west. (For planets other than Earth, mapmakers generally measure all longitudes going west from the prime meridan; what would be 20° east on Earth is treated as 340° west.)
Comparing these results with the System Record Sheets in GURPS Terradyne (one of the few other examples of real planets mapped in GURPS) revealed the Terradyne maps weren't entirely trustworthy. For example, in the Mars map on p. 72 of GURPS Terradyne, the Hellas basin is centered at one of the vertices; 24.12° south, 288° west, to be specific. Hellas is actually at 42° south, 295° west -- a little further west, and much further south. I ended up drawing my own maps based on NASA charts. Included here is a Record Sheet map labeled with a few latitude and longitude guidelines, in case the reader would like to plot other real-world bodies (or well-mapped fictional ones) onto one of these maps.
In The Well contains the Wheeled Vehicle Modular Design System (WVMDS), a modified and simplified subset of the GURPS Vehicles rules. One of the tricks of adapting GURPS Vehicles to a specific setting turned out to be applying names to abstract concepts like "TL8 heavy expensive frame." Being able to put a name to those generic descriptions adds greatly to the flavor.
I knew that the WVMDS had to cover two tech levels: TL8 and TL9, referred to in the setting as "old" and "new." My first pass through the Bodies Table mimicked the Vehicle Bodies Table from p. 108 of GURPS Traveller: Ground Forces, providing different weights for old and new bodies, while all other statistics stayed the same. This is essentially the same system used in the Vehicle Structure Table on p. 19 of GURPS Vehicles. I.e., "All else being equal, structures decrease in weight as TL increases." My original version included a note saying that the WVMDS bodies were assumed to be aluminum if old, and titanium if new.
The inelegancies of this became clear in the section on varying structural materials. Sentences like, "Bodies can be made cheap, which represents steel if old, or aluminum if new," repeated for half-a-dozen different materials, sound quite awkward, and inelegant prose usually indicates inelegant rules. I burrowed into the GURPS Vehicles Vehicle Structure Table to see if I could find a better way.
The key point was remembering that (for example) aluminum doesn't get any stronger as the TL goes up. It just gets obsolete -- ergo, cheaper. If you want to consider aluminum's statistics across TLs, you have to compare "standard" TL8 materials with "cheap" TL9 materials. A little work in Microsoft Excel gave me the following table:
Each number is the basic design weight or cost from the Vehicle Structure Table, for the specified TL, times the appropriate multipliers for different materials. By staggering the TL9 entries down one row, you can compare materials that have similar weights at different TLs -- i.e., they might be the same material, just cheaper. Unfortunately, it's not a perfect fit. Cheap TL8 materials have the same weight per square foot as very cheap TL9 materials, but standard TL9 materials weight half a pound less per sf as cheap TL9 materials. The progression in cost is also not smooth. In some cases, the price of a given material halves from TL8 to TL9, in other places, the reduction is different.
I spent a long time contemplating this, and trying to decide whether to ignore the specific names of materials in the WVMDS (and sacrifice flavor for perfect compatibility), or turn the Vehicle Structure Table on its head (and introduce minor compatibility problems for the purposes of flavor). I eventually went with the latter. The Transhuman Space line intentionally has its own identity distinct from GURPS, and I felt this would give people a better feel for the vehicles they were designing. From the above table, I took an approximation and made it a rule: A given structural material halves in cost at each new TL. My Vehicle Bodies Table ended up listing one weight and one cost for each body size, with the note that old bodies cost twice as much. All I had to do now was provide a list of cost and weight multipliers for each material. These had already been set in the core Transhuman Space book by David Pulver, in the Manufactured Hull Mass and Cost Table. A little more Excel work revealed that if I used aluminum as my default material, the multipliers for the other materials were clean and simple. (If I'd picked, say, titanium, I would have had a table full of "x0.8333..." and the like.) A quick glance at the early-TL8 wheeled vehicles that surround me in the real world revealed this was a workable default material.
This "inverted" way of looking at the Vehicle Structure Table can be applied to other settings and other materials. For example, at TL3 the standard structural material is wood. If the GM wanted to construct a materials table for a fantasy TL3 setting, it might look like this:
The default material would be "Fir," with a basic design weight of 18 lbs./sf and a basic design cost of $5/sf, as given in the Vehicle Structure Table for TLs 2 through 4.
These calculations, and other similar ones, made In The Well a challenge, but a fun one. It's my hope that the setting plays the same way.
Article publication date: February 14, 2003
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