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Operations manual
Star system build specification

Star systems are generated from a build specification using the rules from the World Builder's Handbook. Much of the build specification is optional. The generator will fill in the system as required.

The specification is a YAML document. The document uses two spaces when nesting data. And invalid YAML document, either due to an invalid specification or bad formatting, will not be saved.

Configuration structure

Most fields are optional, but when present they must appear at the correct level. The tree below shows where each section belongs. 

name
surveyIndex:
known:
allegiance:
bases:
primary:
  type:
  class:
  mainWorld:
    uwp:
    orbit:
    name:
  close:
  near:
  far:
counts:
  density:
  terrestrialPlanets:
  planetoidBelts:
  gasGiants:
  mainWorld:
mainWorld:
  uwp:
  orbit:
  name:
populated:
  type:
  allegiance:
  minTechLevel:
  maxTechLevel:
  populationDM:
  minPopulationCode:
  maxPopulationCode:
rogues:

Top-level properties

name
Optional name for the star system.
surveyIndex
Survey index, from 0 to 12. Survey index represents how much information the players have about the star system. When running an exploration game, such as Deepnight Revelation, setting the default to 3 means the stars in the system are known, but nothing else. When running a game in charted space, a survey index of 12 would be appropriate and the IISS has mapped out all the star systems.
known
Boolean. If true, it means the players know about the system. The default is false for an exploration game.
allegiance
Allegiance code for the system. If a code is specified that is not in the database, it will be added. See allegiances for the list of known allegiances.
bases

Sets what bases are present in the star system. The generator does not randomly assign bases, so you will want to specify which ones are present if known. You can always add bases after the system is generated.

Bases are listed as a YAML array. For example, to indicate the system has both a naval and scout base, you would use

bases:
  - S
  - N

You can define what bases are possible using bases.

primary
Optional star definition for the primary star. When laying out the structure of a star system, the primary star is the root; all other stellar objects in the star system are nested under the primary star. See star definition below for the full star specification.
close
Optional star in close orbit around the primary. See star definition below for the full star specification.
near
Optional star in near orbit around the primary. See star definition below for the full star specification.
far
Optional star in far orbit around the primary. See star definition below for the full star specification.
counts
counts is used when the number of terrestrial planets, planetoid belts, and gas giants is know but the placement of them is either not known or does not matter. It can also be used if the star system has a system density rating. See counts definition below.
mainWorld
Optional. Pins the main world's UWP, orbit, and name directly on the star system without requiring a counts entry. Can also be placed directly on any star definition to associate the main world with a specific star. See mainWorld definition below.
populated
populated ensures the system is populated. Use this when a polity settles a region of space. See populated definition below.
rogues
A list of rogue objects to place in the system's hex — objects that do not orbit a star, such as a drifting comet or a rogue planet. A hex may contain more than one rogue object. When replacing a star system, a specification with a rogues entry (even an empty one) replaces the hex's existing rogue objects; a specification without one leaves them alone. See rogue objects definition below.

Star definition

The primary star is the root of the star system. close, near, and far stars can also be specified. Each star can have a companion star orbiting them. A companion star cannot have a companion star. All stars use the same definition, except companion stars do not have a companion entry

See World Builder's Handbook, pg. 27.

primary|close|near|far|companion:
  type
  class
  companion
  bodies
type (required)

Spectral type for the star. For standard stars, use OBAFGKM + 0..9, for example G2. For unusual stars, use one of the codes below. If the star is a unusual star, no class needs to be specified.

Special star types

  • BD: Brown Dwarf
  • D: White Dwarf
  • BH: Black Hole
  • PSR: Pulsar
  • NS: Neutron Star
class (conditionally required)

Luminosity class, I through VI. If type is specified and class is not, class defaults to V unless type is a special type, like a white dwarf.

class can also be giant, which tells the generator to use the giant column when determining the class. See World Builder's Handbook, pg. 15.

companion
Optional companion star nested inside this star definition. A companion cannot have a nested companion.
bodies
Optional list of orbital bodies for this star. If not specified, the generator will assign bodies.
mainWorld
Optional main world definition for this star. Pins the main world's UWP, orbit, and name. Can only be declared once across the entire star system — if set here it must not also appear at the top level or on any other star. See mainWorld definition below.

Counts definition

counts is used when either the number of stellar objects is known and their placement does not matter, or when only the system density is known. counts cannot be used if any star has a bodies list.

Counts must specify either density alone, or all three of terrestrialPlanets, planetoidBelts, and gasGiants. The mainWorld field is optional in both cases. 

counts:
  density:
  terrestrialPlanets:
  planetoidBelts:
  gasGiants:
  mainWorld:
    uwp: (required)
    orbit:
    name:
    moon:

System density is detailed on page 8 in the Deepnight Revelation Referee Handbook.

density
Orbital body density modifier, from 0 to 22+. A value of 0 means the system only contains star(s). The higher the value, the more stellar objects can be found in the system.
terrestrialPlanets
The number of terrestrial planets in the star system.
planetoidBelts
The number of planetoid belts in the star system.
gasGiants
The number of gas giants in the star system.
mainWorld
Optional main world definition.
uwp
The UWP for the main world. This is required.
orbit
The location of the main world. orbit can be either an integer from 1–20, which is the orbit number for the main world, or one of
  • inner: located in the hot zone around the star
  • warm: located in the habitable zone, but closer to the star
  • habitable: located anywhere in the habitable zone
  • hzco: located at the sweet spot of the habitable zone
  • cold: located in the habitable zone, but on the far side of the star
  • outer: located away from the star, outside of the habitable zone
name
name of the main world.
moon
moon is a boolean value. If true, then the main world is a moon orbiting a gas giant. gasGiants must be at least one for moon to be true.

mainWorld definition

mainWorld pins the main world's UWP, orbit, and name. It can appear at the top level of the star system spec or directly on any star definition.

mainWorld may only be declared once per star system, across all forms: the top-level mainWorld key, a star-level mainWorld key, counts.mainWorld, and the mainWorld: true flag on a body in a bodies list all count as a declaration. Using more than one is an error.

mainWorld:
  uwp: (required)
  orbit:
  name:
uwp (required)
The UWP for the main world. Must be an actual UWP code such as X674000-0 or A788699-E. Named types such as terrestrial or gas giant are not accepted here.
orbit
The location of the main world relative to its star. Must be one of:
  • inner: located in the hot zone around the star
  • warm: located in the habitable zone, but closer to the star
  • habitable: located anywhere in the habitable zone
  • hzco: located at the sweet spot of the habitable zone
  • cold: located in the habitable zone, but on the far side of the star
  • outer: located away from the star, outside of the habitable zone
name
Optional name for the main world.

bodies definition

bodies is a list the stellar objects that orbit the star. If specified, only the bodies listed will be generated and placed in orbit around the star. bodies and the top level counts cannot be used together in the same star system.

If you want a star with no orbiting bodies, add orbits as an empty list. 

bodies:
  - uwp
    orbit:
    name:
    mainWorld:
uwp (required)
UWP code such as X674000-0 or one of terrestrial, small gas giant, gas giant, medium gas giant, large gas giant, super earth, or empty. Use super earth to generate a very large terrestrial planet. Use empty to mark the orbit as empty.
orbit

If specified, orbit determines the distance of the stellar object from the star it is orbiting. Only one body can specify its orbit. The permitted values are:

  • inner: located in the hot zone around the star
  • warm: located in the habitable zone, but closer to the star
  • habitable: located anywhere in the habitable zone
  • hzco: located at the sweet spot of the habitable zone
  • cold: located in the habitable zone, but on the far side of the star
  • outer: located away from the star, outside of the habitable zone
name
Optional name for the orbital body.
mainWorld
Boolean. When true, designates this body as the main world. Note this does not mean the world will be populated. An empty star system still has a main world, at least according to the IISS.

Populated definition

populated ensures the system is populated. Use this when a polity settles a region of space. populated can either be true, or can specify additional generation parameters.

populated: true
populated:
  allegiance:
  minTechLevel:
  maxTechLevel:
  minPopulationCode:
  maxPopulationCode:
allegiance
Allegiance code for the system. See allegiances.
minTechLevel
Minimum tech level for the star system
maxTechLevel
Maximum tech level for the star system
minPopulationCode
Minimum population for the primary world in the star system.
maxPopulationCode
Maximum population for the primary world in the star system.

Rogue objects definition

Rogue objects share the hex with the star system but do not orbit any of its stars. They are placed after the system is generated.

rogues:
  - type:
    name:
    known:
type (required)

The kind of rogue object. random rolls on the rogue objects table from page 76 of the World Builder's Handbook; a sensor glitch result creates a phantom object. Planetoids, planetoid belts, gas giants, and terrestrial planets are generated in full; a bare comet or gas giant has its variant chosen randomly. type can be one of the following values:

  • random
  • comet
  • tiny comet
  • medium comet
  • large comet
  • inhabited comet
  • gas giant
  • small gas giant
  • medium gas giant
  • large gas giant
  • planetoid
  • planetoid belt
  • terrestrial planet
  • gas cloud
  • gravity anomaly
  • interstellar wreck
  • phantom object
  • radiation cloud
  • relic
  • space station
  • unusual object
name
An optional name for the rogue object.
known
If true, the object is displayed on player maps.

Sample specifications

Minimal

The simplest valid specification, a blank entry. The system generator will handle everything.

Rogue objects

A random system sharing its hex with a rogue planet and an uncharted drifting wreck.

name: Halvor
rogues:
  - type: terrestrial planet
    name: Cold Halvor
    known: true
  - type: interstellar wreck

Primary Star

Set the primary star and let the generator determine everything else.

name: Grant
primary:
  type: K6
  class: V

TravellerMap

Traveller map has the star types, main world UWP, and a count of the stellar objects in the system.

name: Kinorbes
primary:
  type: G3
  class: V
counts:
  terrestrialPlanets: 8
  planetoidBelts: 3
  gasGiants: 4
  mainWorld:
    uwp: E888765-2
    orbit: habitable

Main world as moon

Specifies body counts explicitly and places the main world as a moon of a gas giant via counts.mainWorld.

name: Vume
counts:
  mainWorld:
    uwp: B100477-C
    orbit: hzco
    name: Vume
    moon: true
  terrestrialPlanets: 1
  planetoidBelts: 2
  gasGiants: 3
primary:
  type: K7
  class: II
bases: []
allegiance: NaHu

Full System Definition

List every stellar object in the star system.

name: Demnan
primary:
  type: F7
  class: V
  companion:
    type: K2
    class: V
  far:
    type: G2
    class: V
  bodies:
    - uwp: terrestrial
    - uwp: large gas giant
    - uwp: planetoid belt
    - uwp: E567000-0
      orbit: habitable
      mainWorld: true
      name: Breakroom
    - uwp: planetoid belt
    - uwp: terrestrial
    - uwp: small gas giant
bases:
  - N
  - S

Using System Density

The system generator will assign stellar objects based on the system density; the higher the density, the higher the number of stellar objects generated. See Deepnight Revelation Referee Handbook, pg. 8. 

name: ALS-BMM
primary:
  type: M6
  class: V
  close:
    type: M8
    class: V
counts:
  density: 12

Reference 0422RD