This application generates a 2D6 SFRPG compatible star-system. It is not based on any particular published system/book, and nor does it reflect modern evolving theories of exoplanets and star system generation, but it should give "classic" looking star systems. For more information on the rationale behind it please read the sections below.
Further enhancements may add moons for worlds, multiple star systems, bases and more world detail (e.g. "places to see").
How To Use
- Enter the star spectral class (AFKGM) and Luminosity (I-D). Note that some Luminosities (VI, VII, D) yield systems usually without viable orbits and have been removed. Multiple star systems are not currently supported.
- Enter the mainworld UWP in the standard format X123456-7
- If required enter the number of Asteroid Belts needed, else random
- If required enter the number of gas giants needed, else random
- The system uses a "Standard" algorithm by default. Unticking sets to Basic which mimics a 1 page manual quick generator in my Distant Stars Arising project.
- Click "Generate", and keep pressing "Generate" until you get a system you like!
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Zones
Four zones are used, Inner, Habitable, Snow and Outer. The mainworld is ALWAYS placed in the habitable zone - gas giant moons are for a later version! Gas giants only occur in the Outer Zone (no Hot Jupiters). Worlds in the Inner/Snow Zone tend to be Rocky, those in the Outer Zone Ice/Rock, some with subsurface oceans.
Placement Order
Gas giants are placed first randomly in the outer zone. Remaining orbits are then populated in order, some are classed as Empty, and a count of Asteroid Belts is maintained (so belts biased to inner orbits).
Worlds
World size is based around D3 or D6, with some hard set to Size 1. Then:
- Atmos: D3 + size - 1, except if hard-coded
- Hydro: 0 if Size or Atmos < 4, else D3 + Atmos - 1
- Pop: Mainworld pop - D6 + DM - 2, where DMs based on Size/Atmos/Hydro.
- Gov: Mainworld Gov + 7 - 2D6, so some link to Mainworld.
- Law: Mainworld Law + 3 - 2D3, so very close to Mainworld.
- Tech: Slightly higher than Mainworld if low tech or hostile (as colonies typically need a decent baseline tech), slightly lower if hi-tech.
- Starport: Mainworld port, local tech level and pop used as DMs to D3 against Spaceport types (XYHGF).
Gas Giants
Gas giants are placed first in the Outer Zone and randomly assigned to Large Gas Giant (LGG) or Small Gas Giant (SGG).
Belts
Belts are rolled randomly with each orbit, so bias to inner orbits if they are limited in number. In Advanced mode relative amounts of Carbonaceous, Metal and Rock asteroids are rolled, with DMs against Carbonaceous and Metal in the Outer system.
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(c) 2020 David Burden/Tau Noyen Publishing - david@burden.name
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