Fleshing out a world

Once you have a subsector sketched out for your Traveller players, the next step is figuring out where in that subsector play is going to start. This will be some world in the subsector, and it makes sense to spend a bit more attention on that to flesh it out than just the UPP and trade code information you have from the subsector stage of prep. Based on the various characters I know will play, it seemed useful to pick a world in the middle of the map: not too near the really civilized worlds; close enough to the edges of easily travelled space to make further exploration more enticing.
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traveller
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Published

February 25, 2019

Since our player group includes a Noble with a yacht, a Scout with access to a scout ship, and several retired marines, it made sense for me to suggest a starting position that would let the group decide to travel either closer to civilization or father from it. Also, based on my decision to divide the kinds of “standard jump routes known” into three kinds (commercial routes available to the public, plus classified routes available only to the scout and naval services), it made sense to pick a world where the routes on either side were accessible for cash, or by using a scout connection.

asteroid mining, futuretimeline

I had already had it in my head that the world of Willesden, since it had a “commercial route in” and “scout routes out”, would likely be more strictly controlled by the Scout service, so I decided to suggest the players start at Edgware, a world two jump-ones from Willesden. Edgware seemed to have several things going for it:

So, settling on Edgware as a starting point, we need to start building it out.

What does B000355/B actually mean?

What we know about Edgeware so far:

Edgware B000355/B Sb, Ni, Gg, Ab

This brief line of stats tells us some interesting stuff, just like knowing the RPG stats for a character can lead us to form a simple picture of what the character is like. Here’s how I described the numbers for my players:

Features. The system has a Scout Base, one or more Gas Giants, and an Asteroid Belt. Its population is a bit too low for it to be an industrial system, but it’s on the verge of industry.

It has a ‘B’ class star base, so refined fuel is available. The Scout base means Scout ships get fuelled by the Scout Service, and the base means that Scouts can have access to service data (i.e. navigation and such).

It has no habitable world in-system; the starport is either in a station orbiting one of the planets or built into an astroid within/on the edge of its astroid belt.

Its population is order of magnitude thousands of people.

The law level of 5 means that personal, concealable firearms are prohibited. Knives of a modest size are permitted, and shotguns are permitted with permits and within certain areas.

The local government is headed by a Governer, separate from the Scout Service personnel (who have their own bureaucracy), who runs the system rather like one might find on a commercial industrial platform or large ship – governance is divided up into departments that are nominally in charge of various technical tasks, and each of those departments has their own reporting structure that all report up into the governor.

Where can we go from here? I decided on two approaches:

  • I’d like to use some of the extended material in Book 6: Scouts and the Near Space original stellar data on the system to bring a bit more physical detail to what’s really there in the system – how many gas giants are there? Where are they? Are there other planets there? How many stars are there? (And perhaps most importantly) what are the general travel times between the features in the system (i.e. distance from starport to jump point, distance from starport to gas giants, and so on). These facts might not help players choose narrative paths, but they will help bring the system alive and act as a backdrop of “known information” to answer simple questions (like “how long do we have to fly in system before we can jump?”)

  • I’d like to use some of the encounter materials from the basic books (or the Starter Traveller versions of them) to flesh out some rumours, patrons, and the like to give the world wider playable texture. These resources will help me support the pushing the first adventure forward and let the players make some choices about what they investigate and follow up on.

The rest of this post will deal with the first of these approaches; I’ll leave the second approach for a subsequent post.

Edgware’s wider system

Traveller’s basic book gives you a way to generate simple data for “the main world” in a system, whatever that main world presence might be: it could be a planet (like Earth), a space-station, a base on a moon surrounding a gas giant, and so forth. Traveller explicitly leaves that up to the referee to decide. Book 6: Scouts gives you a system for helping to further determine detail for a star system beyond just the main world.

The Near Space book provides more information for the system that contains my Edgware:

  • The real-world star system for Edgware is Eggen 372, a single-star system with a real-world spectral type of WD (Near Space uses the code WD to cover all the white dwarf sub-classifications; in reality, I believe that Eggen 372’s currently understood real-world spectral class is DXP9.)

  • The system has one asteroid belt, and one gas giant.

  • The main world’s temperature range is “Cold”“, which isn’t at all surprising given its star.

Star type. The Scouts book does not provide good info for how to use DXP9 spectral types (partly because it seems to me that the DX designation means “we can’t really tell what the spectral type classification for this star should be”), however, if we look at the ISDB indication for its visual luminosity and its apparent diameter, the closest match seems to peg its spectral class at DG as most similar on that basis.

Orbital features. A DG type star is too feeble to have a habitable zone, according to the Scouts book. According to the table of zones, a DG type star has five orbital zones available, all “outer”. First we place the gas giant and belt in the available zones, and determine that none of the other available orbits are empty. Then we generate basic planet attributes for the additional planets in the system, including how many satellites they may have.

One interesting thing to fall out of this process is to note that the Eggen 372/II (the second planet in the system) has two moons, and also has a population of 2 (or, order hundreds). It may be that there’s an outpost further in-system from the asteroid belt that has the main “world” (dubbed “Edgware station”) – why it’s there is for further thought.

Grabbing some names from around Edgware tube station using Google Maps gives us some names to slap on planets in the Edgware system.

Edgware system details
Edgware (Eggen 372) B000355/B
Orbit Feature Satellites Feature UPP
0 Stonegrove (Eggen 372/1) xS000
1 Rectory (Eggen 372/II) 2 x2002
– i
– ii
– Hale station
– iv
– v
– vi
– vii
– viii
4 Whitchurch (Eggen 372/IV) 3 x2000
– i
– ii
– iii

We can dive down another level of detail and figure out if there’s anything on any of those moons that’s meaningful by generating UPP stats for them, too. I won’t bother at this point except to arbitrarily put a “station” of some sort on the third moon of Hale (the gas giant), with population of 1 (order tens).

Travel times. One aspect of this system detail is knowing how long it takes to travel from one place in-system to another. The planetary orbits have radius lengths, so roughly speaking, the travel time between two orbits would range from that value, up to twice the value, depending on where in-orbit the start and end point of a trip are actually relative to one another (in actual fact, because orbits aren’t always circular or arranged on a flat plane, it’s probably more complicated than that, but I only want to know in rough terms what the travel times are between features). For Edgeware’s system then:

calculating travel. Because using a web-browser calculator to do math when you could use Python instead is silly:

import math
def traveltime(km, g):
  da = (km*1000) / (g*9.80665)
  secs = 2 * (math.sqrt(da))
  return 'Hrs: {} Days: {}'.format(
      secs/3600,
      secs/86400
  )
  • Travel from Edgware Station to either Hale, the gas giant, or the outpost on Rectory is a trip of about 70 million km on average; at 1G that’s “about two days”, and at 2G that’s “about a day and a half”.

  • Travel between Rectory and Hale is a trip of about 135 million km on average; at 1G that’s “about two and three-quarter days”, and at 2G that’s “about two days”.

  • Travel from Edgware Station to a jump point is likely pretty fast since the gravity disturbance from the asteroid field is minimal; let’s say the safe jump distance from Edgware is about 80,000 km (about half the distance that’s a safe jump distance from a size 1 world); at 1G that’s “about an hour and a half”, and at 2G that’s “about an hour”.

    Travel from Rectory to a jump point is about 320,000 km; at 1G that’s “just over three hours”, and at 2G that’s “about two and a quarter hours”.

    Travel from Hale to a jump point is long. We can estimate that Hale (as a large gas giant) has a diameter that’s about 230,000 km, and a safe jump distance is 100 diameters, or 23 million km; at 1G that’s a trip of “just over a day”, and at 2G that’s “about three-quarters of a day”.

Scout base. The question of where to put the Scout base is interesting; is it co-located with the main world at Edgware, in the belt? Or is it elsewhere in-system. I like the idea that it’s co-located, providing for cooperation but also cheek-by-jowl tension with the local authority. Thus, the population on Rectory and Hale station are for some reason other than the scout base: listening posts, small scientific research stations, and so forth.

At this point, I think we have all the physical detail for the system that we need. Now we have a better idea of what the system looks like, and how the local lay of the land might look, and we can use that information to help seed some tables for encounters (rumours and patrons, and so on).