Spooky action at a distance

Worlds of Classic Traveller

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Worlds chapter from Classic Traveller Book 03. Modernised and edited with annotations. All values have been preserved to be compatible with the original.

Online generator by Marcia using the tables below.

Star Mapping

The referee has the responsibility for mapping the subsector before a campaign begins. Each hex in a subsector represents the distance that may be covered by an interstellar jump of distance 1 (1 hex = 1 parsec, or 3.26 light years). Use an 8 by 10 hex grid for your subsector map (Hexographer is a solid digital option). You should have around 40 worlds total, which is plenty for a campaign. Give the subsector a name. Label spinward and coreward directions.

World occurrence: roll d6 for each hex, results of 4, 5, or 6 indicate a world is present.

The average distance between two stars in our galaxy is about 5 light years, so Traveller gets quite close to that. What is interesting is that there is actually on average one planet per star in the galaxy. And 1 in 5 Sun-like stars have an Earth sized planet in their habitable zone.

Starport type: roll 2d6 and consult starport table below. Roll 2d6 against the naval and scout base thresholds to see if any are present. Scout bases always offer refined fuel for scouts.

2d6 Type Fuel Facilities Bases
2-4 A: Excellent Refined Annual maintenance overhaul, starship shipyard Naval: 8+, Scout: 10+
5-6 B: Good Refined Annual maintenance overhaul, non-starship shipyard Naval: 8+, Scout: 9+
7-8 C: Routine Unrefined Reasonable repair Scout: 8+
9 D: Poor Unrefined None Scout: 7+
10-11 E: Frontier None None None
12 X: None None None None

Route determination: consult starport types of nearby (within 4 hexes) worlds and the jump distance between them. If you roll a d6 equal or over the target number (on the row/column intersection), there is a route between them. Draw a line connecting the two worlds on the map. So if a PORT-A and a PORT-B worlds are 2 hexes away, I would need to roll 3 or higher for there to be a connection between them.

While it is possible for starships to travel without regard to the lanes charted, individuals who do not own starships are restricted to commercial travel on mapped routes.

World Pair Jump-1 Jump-2 Jump-3 Jump-4
A—A 1+ 2+ 4+ 5+
A—B 1+ 3+ 4+ 5+
A—C 1+ 4+ 6
A—D 1+ 5+
A—E 2+
B—B 1+ 3+ 4+ 6
B—C 2+ 4+ 6
B—D, C—C 3+ 6
B—E, C—D, C—E, D—D 4+
D—E 5+
E—E 6

Ignore longer links if shorter jumps links can be used. So ignore a JUMP-2 link if two JUMP-1 links already exist between these worlds. Once generated, you should have a map of star systems in relation to each other through relative distance and space lane connections.

World Creation

Each world should be allocated at least one page in a campaign notebook maintained by the referee. As characteristics are generated, they should be recorded along with the name of the world and its location (generally its subsector and hex number). In addition, the referee should generate other information which may be pertinent. This may include details of other planets in the star system, radiation characteristics of the star, the types of terrain present on the planetary surface, unique encounter tables, data on flora and fauna, industrial or agricultural capacity, data on social structure and government, or possibly actual maps of the planetary surface.

Traveller gives solid advice on noting down your worlds, but also expects a lot of independent research into planetary sciences. Luckily nowadays it is easier to do than ever with the internet. I’d recommend checking out Atomic Rockets on this topic.

Planetary size (SIZE): 2d6—2. SIZE represents thousands of miles of the planet’s diameter. Zero indicates an asteroid/planetoid complex. SIZE can be used to determine gravity. My friend Comrades idea was to add/subtract item slots per world difference from 7 (which matches nicely with Classic Traveller B01).

Traveller worlds average at about twice as small as Earth (5 thousand miles compared to 8 thousand). Current studies have shown that most of the galaxy is actually populated by planets larger than Earth by 1.5 or 2 times (also called superearths). However, larger sized planets are easier to find, so we might be missing a lot of tiny stellar bodies.

Planetary atmosphere (ATMO): 2d6–7 + SIZE, consult table below.

  • If SIZE is 0, ATMO is 0.
Total Atmosphere Gear
0 None Vacc Suit
1 Trace Vacc Suit
2 Very thin, tainted Respirator, Filter
3 Very thin Respirator
4 Thin, tainted Filter
5 Thin
6 Standard
7 Standard, tainted Filter
8 Dense
9 Dense, tainted Filter
10 Exotic Air Supply
11 Corrosive Vacc Suit
12 Insidious Vacc Suit

Hydrographic percentage (HYDR): 2d6–7 + SIZE, total x10 represents percentage of surface covered by water. A total of 6, means 60% of surface is submerged.

  • SIZE of 0 or 1 will always mean HYDR 0.
  • If ATMO is 0, 1 or 9+, modify total HYDR by –4.

Water is actually quite frequent in space, but most of it is frozen in perpetual ice. I assume that terraforming widespread in the universe Traveller. Worlds are artificially heated and their water is allowed to flow.

Population (POP): 2d6–2. POP represents exponents of 10 (zeroes after 1) of inhabitants. So a total of 5 would mean approximately 100,000 people. POP 0 planets are barren. Optionally you can roll d6 for population density. Result of 1 being an evenly spread out population, and on 6 the population is concentrated in a single city. Other results are on a spectrum between the extremes.

Average planet population is surprisingly small. 100 thousand people is the size of an average town, while the population of our own planet is approaching 10 billion. This implies that the subsectors of Traveller are located on the outer rim of known space. Newly colonised and settled worlds are more likely to be encountered.

Planetary government (GOV). 2d6–7 + POP. The planetary government table gives a brief description of the general characteristics of each government type. Disunion is a special result, meaning the referee should generate the specific qualities of each territory on the planet separately.

Total Government Type Description
0 No government Family bonds predominate.
1 Company/Corporation Company managerial elite, citizenry are employees.
2 Participating Democracy Decisions are reached by consent of citizenry directly.
3 Self-Perpetuating Oligarchy Restricted minority with little to no impute from citizenry.
4 Representative Democracy Functions are performed by elected representatives.
5 Feudal Technocracy Functions are performed by individuals for those who agree to be governed by them. Relationships are based on performance of technical activities.
6 Captive Government Leadership is imposed by an outside group.
7 Disunion No central ruling authority exists. Law level refers to nearest starport area.
8 Civil Service Bureaucracy Functions are performed by individuals chosen for their expertise.
9 Impersonal Bureaucracy Agencies are insulated from the governed citizens.
10 Charismatic Dictator Agencies directed by a single leader backed by the citizenry.
11 Non-Charismatic Leader A previous charismatic dictator has been replaced.
12 Charismatic Oligarchy A ruling class enjoys the confidence of the citizenry.
13 Religious Dictatorship Functions performed by religious organisation.

Law level (LAW). 2d6–7+ GOV. In addition to weapons and arms controls, law levels indicate the roll for law enforcement harassment for violations. For example, a person on a world of LAW 4 would have to roll 4+ to avoid arrest when encountering an enforcement agent.

Law level does not apply to persons and ships at a starport, as local laws do not apply in such areas.

LAW Prohibitions
0 None
1 Body pistols which are undetectable by standard detectors, explosive weapons such as bombs or grenades, and poison gas
2 Portable energy weapons, such as laser rifles or carbines
3 Weapons of a strict military nature (such as machine guns or automatic rifles, not submachine guns)
4 Light assault weapons (such as submachine guns)
5 Personal concealable firearms (such as pistols and revolvers)
6 Most firearms (all except shotguns), open carry is discouraged
7 Shotguns
8 Open possession of long bladed weapons (all blade weapons except daggers)
9 Any weapon

Each law level includes all prohibitions of levels numbered lower than it. For example, shotguns are prohibited at all law levels from 7 higher.

Technological index (TECH): d6 + modifiers determined from the table below.

Type -4 -2 +1 +2 +4 +6
SIZE 0-1 2-4
ATMO 0-3 & 10-14
HYDR 9 10
POP 1-5 9 10
GOV 13 0 & 5

TECH represents the general quality and capability of local industry.

In my sci-fi games I like to mix varying tech levels, making interesting worlds and cultures to explore. Instead of a linear progression, I would note tech as a combination of factors. For example a planet using solar power because of the abundance of sunlight, but still resorting to swords because of a lack of ammunitions.

TECH Type Description
0 None Spears, carts
1-3 Pre-industrial Galley, sword, cannons
4 Industrial Revolvers, telephones, steamships
5-6 Computational Computers, television, rifles
7-8 Basic interstellar Fusion, non-starships, solar, hovercraft, pulse weapons
9-16 Imperial interstellar Laser weapons, starships, battle dress, artificial gravity
17+ Esoteric Anti-matter, artificial intelligence

Trade Codes

Optional classifications based on Book 02 and Mongoose Core. Trade codes are used in order to establish a world’s supply and demand. If not fitting criteria, it is counted as roughly average. A world may meet the criteria for more than one label.

Classification Description Requirements
Agricultural (Ag) Supply of organic goods. ATMO: 4-9, HYDR: 4-8, POP: 5-7
Non-agricultural (Na) Demand for organic goods. ATMO: 0-3, HYDR: 0-3, POP: 6+
Industrial (In) Supply of fabricated goods. ATMO: 0-2, 4, 7 or 9, POP: 9+
Non-Industrial (Ni) Demand for fabricated goods. POP: 0-6
Rich (Ri) Supply of material. ATMO: 6 or 8, POP: 6-8, GOV: 4-9
Poor (Po) Demand for material. ATMO: 2-5, HYDR: 0-3
High population (Hp) Supply of cultural goods. POP: 5+
Low population (Lp) Demand for cultural goods. POP: 1-3
Low security (Ls) Supply of contraband. LAW: 0-2
High security (Hs) Demand for contraband. LAW: 6+
High technology (Ht) Supply of technology. TECH: 12+
Low technology (Lt) Demand for technology. TECH: 0-5

Name each world and note their hex number location in the subsector. Note previously generated starport type. Convert to Universal World Profile if needed (10=A, 11=B etc).

Example world card:

NADIR PRIME     E572366-5
Frozen desert planet. Atmosphere is rich in carbon dioxide due to a 
lack of plantlife. Population in thousands governed by colonial 
administration of House Ghaiad. Fission reactors sustain ice mining 
colonies. The ice is transferred to makeshift landing zones, from where 
it is shipped offworld.

Published on June 17, 2022.

Tagged: setting   worldbuilding   space   traveller   sandbox   mindmeld  


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