TEXT:  
  Artwork: David A. Hardy 
   
   
   
   
  Star System Generator 
   
  Larry Moore  
  Revision: 01/26/2009 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
  Page 1 
   
  1: Introduction 
  This system is based on current astronomical knowledge and leans towards more randomness in a 
  campaign setting. This author believes that we are unique in the universe and it’s highly unlikely a star 
  system would contain the astronomical thresholds to sustain complex life; therefore you will find several 
  deviations from known science in many areas. It’s science fiction after all. Enjoy and have fun playing 
  with friends and family.  
  1.1: Overview 
  Generating a system is basically rolling on a series of tables and recording the results. If you 
  need a single planet for your campaign you do not need to start ‘at the top’ of the tables and roll 
  your way down. Simply pick the section of this document that relates to the planet or feature 
  you desire. Don’t be a slave to the dice! 
  I have broken the sections down as follows; 
  • 
  2) Number and Type of stars 
  • 
  3) Number of Zones and Distance of each Zone 
  • 
  4) Astronomical Objects in each Zone (planet, asteroid belt, etc…) 
  • 
  5) Common Planetary Tables 
  o Mass, Diameter, Gravity, Moons, Rings and Features 
  • 
  6)Habitable Planet Tables 
  o Length of day, Land/Water percentages, Atmospheric conditions, Radiation 
  levels and Climate 
  • 
  7)Example star system 
  • 
  Star System Record Sheet (Separate print out) 
  2: Stars 
  The following tables cover the number of stars in a system and the type of each star.  
  2.1: Number of stars table 
  d100 
  Number of stars 
  01-62 
  Single 
  63-91 
  Double 
  92-97 
  Triple 
  98-99 
  Quadruple 
  100 
  1d5+4 Stars 
   
   
   
  
  Star Systems Generator | Larry Moore 
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  For each star roll d100 and consult the table below.  
  2.2: Stellar classification table 
  d100 
  Star  
  type 
  Color 
  Number of Zones 
  Die Code 
  Habitable Zone  
  Number 
  01-05 
  0 
  Blue 
  1d10+6 
  11 
  06-13 
  B 
  Blue-white 
  1d10+4 
  9 
  14-25 
  A 
  White 
  1d10+2 
  7 
  26-45 
  F 
  Yellowish-white 
  1d10+2 
  5 
  46-70 
  G 
  Yellow 
  1d10+2 
  3 
  71-90 
  K 
  Orange 
  1d5+2 
  2 
  91-00 
  M 
  Red 
  1d5 
  1 
   
  2.3: Star color and relative size chart 
   
   
   
   
   
   
   
  3: Zones  
  3.1: Number of zones 
  Next we need to determine how many orbital zones are in the star system. Roll the die code 
  determined in table 2.2.  
  For instance, if you rolled 22 and got an A star, you would roll 1d10+2 for the number of 
  zones in this star system. 
  3.2: Zone Distance 
  Next we determine the distance each zone is from the home star. The table below lists the zone 
  range, chose a value between the ranges. This is the zones distance in AUs. If you roll up binary 
   
  M 
  K 
  G 
  F 
  A
  B 
  O 
  
  Star Systems Generator | Larry Moore 
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  planet, they can follow the same orbit or each can have a separate orbit. As long as they are in 
  the zone range given in the table.  
   
  How to read the Zone Distance Table. 
  • 
  Numbers represent the distance from the star (in AU) the orbital zone resides. 
  • 
  Red represents zones whose worlds tend to be infernos.  
  • 
  Orange represents zones whose worlds tend to be quite hot. 
  • 
  Green represents a habitable zone.  If a terrestrial world (or a large enough moon to a 
  Jovian) exists here with the right conditions, it can be habitable. 
  • 
  Light blue represents zones that have a tendency - due to distance from the star - to 
  have cold worlds. 
  • 
  Dark blue represents zones that have a tendency for very cold worlds/ice rocks. 
  • 
  The zone colors have the following terms (Near, Inner, Habitable, Outer and far); 
  Red = Near 
  Orange = Inner 
  Green = Habitable 
  Light Blue = Outer 
  Dark Blue = Far 
  3.3: Zone Distance Table (in AU) 
  Zone# 
  O 
  B 
  A 
  F 
  G 
  K 
  M 
  1 
  20.0 - 29.9 
  10.0 - 14.9 
  0.7 - 1.3 
  0.2 - 0.3 
  0.4 - 0.5 
  0.2 - 0.3 
  0.2 - 0.3 
  2 
  30.0 - 44.9 
  15.0 - 22.4 
  1.4 - 2.7 
  0.4 - 0.5 
  0.6 - 0.8 
  0.4 - 0.7 
  0.4 - 0.7 
  3 
  45.0 - 67.4 
  22.5 - 33.7 
  2.8 - 5.5 
  0.6 - 1.0 
  0.9 - 1.3 
  0.8 - 1.5 
  0.8 - 1.5 
  4 
  67.5 - 101.2 
  33.8 - 50.5 
  5.6 - 11.1 
  1.1 - 1.8 
  1.4 - 1.9 
  1.6 - 3.1 
  1.6 - 3.1 
  5 
  101.3 - 151.8 
  50.6 - 75.8 
  11.2 - 22.3 
  1.9 - 3.2 
  2.0 - 2.9 
  3.2 - 6.3 
  3.2 - 6.3 
  6 
  151.9 - 227.7 
  75.9 - 113.8 
  22.4 - 44.7 
  3.3 - 5.6 
  3.0 - 4.5 
  6.4 - 12.7 
   
  7 
  227.8 - 341.6 
  113.9 - 170.8 
  44.8 - 89.5 
  5.7 - 10.0 
  4.6 - 6.7 
  12.8 - 25.5 
   
  8 
  341.7 - 512.5 
  170.9 - 256.2 
  89.6 - 179.1 
  10.1 - 17.5 
  6.8 - 10.2 
   
   
  9 
  512.6 - 768.8 
  256.3 - 384.3 
  179.2 - 358.3 
  17.6 - 30.7 
  10.3 - 15.3 
   
   
  10 
  768.9 - 1,153.2 
  384.4 - 576.6 
  358.4 - 716.7 
  30.8 - 53.8 
  15.4 - 23.0 
   
   
  11 
  1,153.3 - 1,729.9 
  576.7 - 864.9 
  716.8 - 1,433.5 
  53.9 - 94.2 
  23.1 - 34.5 
   
   
  12 
  1,730.0 - 2,594.8 
  865.0 - 1,297.4 
  1,433.6 - 2,867.1 
  94.3 - 164.9 
  34.6 - 51.8 
   
   
  13 
  2,594.9 - 3,892.3 
  1,297.5 - 1,946.1 
   
   
   
   
   
  14 
  3,892.4 - 5,838.5 
  1,946.2 - 2,919.2 
   
   
   
   
   
  15 
  5,838.6 - 8,757.8 
   
   
   
   
   
   
  16 
  8,757.9 - 13,136.7 
   
   
   
   
   
   
  * Colors indicate the distances of Near, Inner, Habitable, Outer and Far. 
   
   
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
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  4: Astronomical Objects 
  Now that we have zones, let’s fill them. Zones can be filled with dwarf, terrestrial, habitable, Jovian 
  planets or asteroid belts.    
  4.1: Astronomical Object Table 
  d100 
  Astronomical Object 
  01-12 
  Empty 
  13-24 
  Asteroid Belt 
  25-42 
  Dwarf 
  43-70 
  Terrestrial (If in Habitable zone, planet may be habitable.) 
  71-94 
  Jovian (Roll d10, even = Ice, odd = Gas) 
  95-00 
  Binary planet, co-populated: Roll twice 
  * Jovian planets that are located in zone one are always gas. They are sometimes referred to as 
  “Hot Jovian” due to the temperature from the home star.  
  4.2: Asteroid Belt Tables 
  D10 Size 
   
  D10 Population Density 
  1-2 
  Tiny 
   
  1-2 
  Sparse 
  3-4 
  Small 
   
  3-4 
  Light 
  5-6 
  Medium 
   
  5-6 
  Moderate 
  7-8 
  Large 
   
  7-8 
  Dense 
  9-0 
  Huge 
   
  9-0 
  Very Dense 
  * This table is optional and is used to determine the size and population density of an asteroid 
  belt. 
  5: Common Planetary Tables  
  Before the four races encountered each other they used their home planet as the stick by which to 
  measure their own solar system. As the races encountered one another, each had a unique and distinct 
  world, they needed a standard. Thus the planetary galactic standard was born and is noted as “Galactic 
  Standard”.  
  1.0 Galactic Standard AU = 150,000,000 km  
  1.0 Galactic Standard Mass = 5.9E+24 kg 
  1.0 Galactic Standard Diameter = 12,467 km  
  1.0 Galactic Standard Gravity = 9.8m/s2 (Escape velocity (km/s) = 11.186) 
  1.0 Galactic Standard Year = 365.25 Galactic Standard days 
  1.0 Galactic Standard Day = 24 Galactic Standard hours 
  1.0 Galactic Standard Hour = 60 Galactic Standard minutes 
  1.0 Galactic Standard Minute = 60 Galactic Standard seconds 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
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  1.0 Galactic Standard Radiation Exposure = 2.4 millisievert (mSv) per year. 
  1.0 Galactic Standard Atmospheric Pressure = 1.033 kg/m3 
  At this point it’s time to define mass, diameter, and gravity to length of day, atmospheric conditions and 
  so forth for each planet. Referee’s can define statistics on the following tables for each planet or define 
  only the ones that are important to the campaign, (they can always be defined later if needed). Note 
  that we have provided a list of pre-rolled planets in section 5.2.  
  5.1: Mass, Diameter and Gravity Table 
  In FrontierSpace(TM) there are 4 categories of planets. Dwarf, Jovian, Terrestrial and Habitable. 
  Jovian’s are further broken down into Ice Jovians and Gas Jovians. Each planet has the following 
  common characteristics; Mass, Diameter and Gravity. Now that you have filled in each zone use the 
  table below for each type of astronomical object. 
  Type 
  Mass, Diameter and Gravity* 
  Jovian, Ice 
  Gravity  
  Diameter 
  Mass 
  Moons 
  d100 x 0.05  
  (1d10+12) /4  
  Gravity * Diameter * Diameter 
  Moon Table 
  Jovian, Gas 
  Gravity  
  Diameter 
  Mass 
  Moons 
  d100 x 0.05 
  (1d10+15) / 2 
  Gravity * Diameter * Diameter 
  Moon Table 
  Dwarf 
  Gravity  
  Diameter 
  Mass 
  Moons 
  d100 / 30  
  6d10 x 0.01 
  Gravity * Diameter * Diameter 
  Moon Table 
  Terrestrial 
  Gravity  
  Diameter 
  Mass 
  Moons 
  (2d10+2) / 10 
  (1d100+40) / 70 
  Gravity * Diameter * Diameter 
  Moon Table 
       * If habitable Gravity = .7 to .1.5 
  * All ratings are in Galactic Standard Masses / Diameters / Gravities. 
   
  ** Optional Gas Giant Resources and Precious Resources tables are located below. 
  • 
  Jovian planets are large planets that are not primarily composed of silicates or other solid 
  matter and lack a clearly defined surface. They are subdivided into two categories, gas giants 
  and ice giants. Gas giants are primarily composed of hydrogen and helium while ice giants are 
  mostly composed of water, ammonia and methane.  
  • 
  Dwarf planets are typically smaller than terrestrial planets, do not have secondary atmospheres 
  and have not cleared their orbital path of all other bodies.   Sometimes, dwarf planets can be 
  found as moons orbiting larger planets (especially large gas giants) and in these cases, if 
  conditions are right, may be habitable.  
  
  Star Systems Generator | Larry Moore 
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  • 
  Terrestrial planets have roughly the same structure: a central metallic core (mostly iron) with a 
  surrounding silicate mantle. These planets have canyons, craters, mountains and volcanoes. 
  Terrestrial planets possess secondary atmospheres unlike Jovian (gas giants) which possess 
  primary atmospheres. Terrestrial planets are also called “rocky planets”. 
  5.2: Pre-Defined Planets 
  Note that some values are not expressed in the tables because they are dependant on the orbital zone. 
  Radiation, Temperature, and Length of Year will need to be determined separately if that is important to 
  your planet. Also be aware that depending on where the planet lies in the zones; land, water and ice 
  percentages may not apply. For instance planets in the Near or Inner zones would have their water and 
  ice burned off due to heat from the star. Planets in the Outer and Far zones would have mostly ice if 
  water was present. 
   
  Dwarf 
  d10 Gravity Diameter Mass #Moons 
  Day 
  Land Ice Liquid 
  Pressure 
  Toxicity 
  Axial Tilt 
  1 
  1.3 
  0.43 
  0.24 
  -- 
  20hrs 
  60% 11% 
  29% Very Thin 
  Trace Toxins 
  0 deg 
  2 
  0.3 
  0.39 
  0.04 
  -- 
  18hrs 
  32% 15% 
  53% Very Thin 
  Moderately 
  Toxic 
  1 deg 
  3 
  1.0 
  0.33 
  0.11 
  -- 
  21hrs 
  68% 19% 
  13% Thin 
  Trace Toxins 
  25 deg 
  4 
  1.9 
  0.35 
  0.23 
  -- 
  644hrs 20% 13% 
  67% Thin 
  Trace Toxins 
  1 deg 
  5 
  0.9 
  0.42 
  0.15 
  -- 
  22hrs 
  48% 10% 
  42% Very Thin 
  Non-toxic 
  38 deg 
  6 
  1.1 
  0.27 
  0.08 
  4 
  96hrs 
  28% 12% 
  60% Very Thin 
  Trace Toxins 
  27 deg 
  7 
  0.3 
  0.24 
  0.01 
  -- 
  27hrs 
  72% 17% 
  11% Very Thin 
  Trace Toxins 
  45 deg 
  8 
  0.2 
  0.35 
  0.03 
  1 
  26hrs 
  72% 15% 
  13% Very Thin 
  Lethally Toxic 
  41 deg 
  9 
  1.7 
  0.32 
  0.17 
  -- 
  16hrs 
  80% 
  8% 
  12% Very Thin 
  Non-toxic 
  9 deg 
  10 
  0.3 
  0.48 
  0.07 
  -- 
  12hrs 
  60% 19% 
  21% Very Thin 
  Trace Toxins 
  9 deg 
   
  Terrestrial 
  d10 Gravity Diameter Mass #Moons 
  Day 
  Land Ice Liquid 
  Pressure 
  Toxicity 
  Axial Tilt 
  1 
  1.8  
  0.87  
  1.37  
  1  
  729hrs 80%  12%  
  8%  Dense  
  Trace Toxins  
  25 deg 
  2 
  1.4  
  0.91  
  1.17  
  1  
  396hrs 40%  11%  49%  Dense  
  Trace Toxins  
  37 deg 
  3 
  0.8  
  0.73  
  0.42  
  1  
  11hrs 75%  12%  13%  Very Thin  
  Severely Toxic  
  40 deg 
  4 
  0.5  
  1.66  
  1.37  
  1  
  430hrs 20%  16%  64%  Moderate  
  Lethally Toxic  
  13 deg 
  5 
  1.7  
  0.80  
  1.09  
  --  
  19hrs 15%  6%  
  79%  Moderate  
  Trace Toxins  
  32 deg 
  6 
  0.6  
  0.80  
  0.38  
  1  
  5.5hrs 55%  8%  
  37%  Thin  
  Non-toxic  
  45 deg 
  7 
  1.7  
  0.59  
  0.58  
  --  
  23hrs 15%  5%  
  80%  Thin  
  Non-toxic  
  25 deg 
  8 
  1.3  
  1.49  
  2.87  
  --  
  24hrs 60%  5%  
  35%  Very Dense  Severely Toxic  
  11 deg 
  9 
  1.0  
  2.00  
  4.00  
  --  
  248hrs 45%  19%  36%  Dense  
  Lethally Toxic  
  27 deg 
  10 
  1.0  
  0.73  
  0.53  
  2  
  32hrs 45%  4%  
  51%  Thin  
  Trace Toxins  
  19 deg 
   
  Jovian, Ice 
  d10 Gravity Diameter Mass #Moons 
  Day 
  Land Ice Liquid 
  Pressure 
  Toxicity 
  Axial Tilt 
  1 
  2.35 
  4.25 
  42.45 
  52 
  43hrs 
  % 
  % 
  % 
  Dense  
  Severely Toxic 
  0 deg 
  2 
  5 
  5.5 
  151.25 
  62 
  10hrs 
  % 
  % 
  % 
  Dense  
  Lethally Toxic 
  22 deg 
  3 
  1.05 
  3.75 
  14.77 
  0 
  15hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic  
  12 deg 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
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  4 
  2.25 
  3.25 
  23.77 
  16 
  55hrs 
  % 
  % 
  % 
  Very Dense Lethally Toxic  
  40 deg 
  5 
  3.2 
  5.25 
  88.2 
  48 
  26hrs 
  % 
  % 
  % 
  Dense 
  Severely Toxic 
  11 deg 
  6 
  0.9 
  3.25 
  9.51 
  6 
  30hrs 
  % 
  % 
  % 
  Very Dense Lethally Toxic 
  25 deg 
  7 
  1.65 
  4.25 
  28.80 
  24 
  10hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  35 deg 
  8 
  3.8 
  5 
  95 
  64 
  288hrs 
  % 
  % 
  % 
  Very Dense  Severely Toxic  
  15 deg 
  9 
  2.2 
  4.75 
  49.64 
  54 
  37hrs 
  % 
  % 
  % 
  Dense  
  Lethally Toxic  
  17 deg 
  10 
  1.4 
  3.5 
  17.15 
  18 
  200hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  27 deg 
   
  Jovian, Gas 
  d10 Gravity Diameter Mass #Moons 
  Day 
  Land Ice Liquid 
  Pressure 
  Toxicity 
  Axial Tilt 
  1 
  2.95 
  12.5 
  460.94 
  44 
  29hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  30 deg 
  2 
  1.1 
  9.5 
  99.28 
  70 
  23hrs 
  % 
  % 
  % 
  Dense  
  Lethally Toxic 
  0 deg 
  3 
  1.8 
  11 
  217.8 
  40 
  32hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic  
  29 deg 
  4 
  3.85 
  8 
  246.4 
  48 
  15hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  17 deg 
  5 
  2.1 
  9.5 
  189.53 
  38 
  370hrs 
  % 
  % 
  % 
  Dense 
  Severely Toxic 
  31 deg 
  6 
  4.55 
  12.5 
  710.94 
  24 
  434hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  25 deg 
  7 
  3.1 
  9 
  251.1 
  64 
  54hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  3 deg 
  8 
  2.1 
  10.5 
  231.53 
  42 
  29hrs 
  % 
  % 
  % 
  Dense 
  Severely Toxic 
  26 deg 
  9 
  .65 
  11 
  78.65 
  24 
  8hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  13 deg 
  10 
  2.65 
  10 
  265 
  38 
  190hrs 
  % 
  % 
  % 
  Very Dense Severely Toxic 
  10 deg 
   
  5.3: Moon, Rings and Features 
  Once the mass has been determined consult the following table to determine the moons, rings and 
  features orbiting the planet. 
  5.3.1: Moon Table 
  Mass 
  d10 
  Result 
  0-2 
  01-05  
  06-08 
  09 
  10 
  No moon  
  A single moon 
  1d5 moons   
  1d5 moons + Feature Table 
  2.1-14.99 
  01-02  
  03-05 
  06-07 
  08-09 
  10 
  No moon or ring 
  1d5 moons 
  1d5 +1 moons + 20% chance of a ring 
  1d5 moons + Feature Table 
  1d10 moons + Feature Table 
  15-25 
  01-02  
  03-06 
  07-09 
  10 
  1d10 x 2 moons 
  2d10 x 2 moons + 30% of a ring of 1d5 rings 
  2d10 x 3 moons + Feature Table 
  3d10 x 2 moons + 30% 1d5 rings + Feature Table 
  26-130 
  01-05 
  06-09 
  10 
  4d10 x 2 moons + 30% chance of 1d5 rings 
  5d10 x 2 moons + 1d10 rings 
  Feature Table + 4d10 x 2 Moon + 1d10 Ring 
  
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  130+ 
  01-05 
  06-09 
  10 
  4d10 x 2 moons + 1d10 rings 
  Feature Table + 4d10 x 2 Moon + 1d10 Ring 
  5d10 x 2 moons + 1d10 rings 
  5.3.2: Habitable Moons 
  Some moons are large enough to be considered a minor planet and may in fact sustain life. Use 
  the Dwarf table (5.1) to determine mass, diameter, and gravity.  If conditions are sufficient (and 
  the planet this moon orbits is in its star's habitable zone) then this moon may support life. 
  5.3.3: Feature Table 
  d100 
  Result 
  Description 
  01-10 
  Alien deep-space 
  life form 
  Some unknown creature, able to life in deep-space without the 
  need for life-support is found. 
  11-20 
  Ancient Ruins 
  Ruins and remnants of ancient civilization that predates current 
  cultures by (roll 1d100x100) years. 
  Roll d10: 01-04 on planet, 05-09 on moon, 10 both 
  21-30 
  Alien artifact 
  An alien device floats in space. Possibilities are mines, ships, 
  hulks, probe, etc... 
  31-40 
  Doomsday planet 
  A large comet or rogue world passes by every (1d100x10) years. 
   It is calculated that in (1d100x100) years, it will collide with the 
  either the planet or its moon, either of which is disastrous for 
  this world. 
  41-50 
  Roll twice more 
   
  51-60 
  Artificial moon 
  The moon has been drastically altered or manufactured by 
  unknown beings. There is a 10% chance this is a Dyson moon. 
  61-70 
  Ringed Moon 
  The moon collided with a large meteor several thousand years 
  ago.  The debris from it has been caught by the mass of the 
  moon and looks like a ring when viewed from the planet's 
  surface.  The debris has value (roll on the mineral resource 
  table). 
  71-80 
  Derelict ship 
  A spacecraft in deep space. Possibilities include a ship 
  abandoned after a pirate attack, a lost STL (slow than light) ship 
  configured as a colony, research or probe. 
  81-90 
  Electromagnetic 
  atmospheric 
  conditions 
  The planet has atmospheric reactions to the presence of one or 
  more of its moons.  As the moon streaks across the sky, the 
  atmosphere produces aurora borealis-like light shows. 
  91-00 
  Glowing Moon 
  Natural photoluminescent aluminate minerals are present on 
  one of this world's moon's surfaces.  It glows in the dark rather 
  than just reflecting light, never letting the world see complete 
  darkness. 
   
   
   
   
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
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  ** The following tables are optional and are used to determine if anything of value is located on 
  gas and terrestrial planets. 
  5.3.4: Gas Giant Resource Table (optional) 
  If mining gas giants is important to your campaign this table is for you. 
  d10 
  Main Gas 
  % 
  Trace Gas 
  1 
  Hydrogen, Helium 
  90/10 
  Water, Methane, Ammonia 
  2 
  Hydrogen 
  99 
  Helium, Water, Methane, 
  Ammonia 
  3 
  Carbon dioxide, Hydrogen, Helium 
  20/60/20 
  Ammonia, Fluorine, Argon 
  4 
  Hydrogen, Methane 
  90/10 
  Hydrogen deuteride 
  5 
  Complete Mix 
  -- 
  -- 
  6 
  Fluorine, Methane, Ammonia 
  33/33/33 
  Water, Ethane 
  7 
  Hydrogen, Helium 
  10/90 
  Water, Ammonia 
  8 
  Neon/Argon 
  25/75 
  Water, Methane, Ethane, 
  Ammonia, Fluorine 
  9 
  Hydrogen, Helium 
  80/20 
  Water, Methane, Ammonia 
  10 
  Water, Ammonia, Methane 
  30/30/40 
  Hydrogen 
  5.3.5: Terrestrial Precious Resource Table (optional) 
  d10 
  Type 
  1 
  Metal Ore (low grade) 
  2 
  Precious Metal(s) 
  3 
  Radioactive Ore 
  4 
  Metal ore (high grade) 
  5 
  Precious Gem(s) 
  6 
  Silicates (no mineral value) 
  7 
  Raw crystals 
  8 
  Minerals (high grade) 
  9 
  Metal Ore (low grade) 
  10 
  Roll twice more 
  * A Referee can roll d1000 to determine the quantity.  
  1,000 kilograms = 1 ton = 2000 lbs 
  6: Planetary Features  
  Use this set of tables to determine very specific information about a planet.  Mostly for Terrestrial 
  worlds, this process can be used to determine facts about Dwarf planets and moons of Jovians too.   
  Terrestrial planets have a central metallic core (mostly iron) with a surrounding silicate mantle. These 
  planets have canyons, craters, mountains and volcanoes. If a terrestrial planet is in the habitable zone of 
  
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  a star system there is a chance that it can support life. Note that if your goal is a habitable planet use 
  values in the tables below that will support life.  
  6.1 Length of Day 
  The length of day is often confused with “rotation period” (the time it takes a planet to 
  complete one revolution around its axis of rotations relative to the background stars).  Length of 
  day refers to the average time (in Galactic Standard Hours) for the planet’s star to move from 
  the noon position in the sky at a point on the equator back to the same position.   To determine 
  this value, roll on the following table (then roll for the number of hours in the day): 
  1d10 
  Result 
  Galactic Standard Hours 
  1 
  Very fast length of day 
  2d10/2 hours 
  2-3 
  Fast length of day 
  2d10 hours 
  4-7 
  Moderate length of day 
  4d10+2 hours 
  8-9 
  Slow length of day 
  1d100x1d10 hours 
  10 
  Very slow length of day 
  1d100x1d100 hours 
  6.2 Land Mass Percentages 
  Each planet has a different biosphere that is a result of the percentages of land, water and ice. 
  Use the following formulas to determine each value. Don’t be a slave to the dice, feel free to mix 
  and match as you see fit. 
  Percentage of Liquid = 2d10 x 5 (could be water, or other liquids) 
  Percentage of Ice = 2d10 (frozen water or other frozen liquids) 
  Percentage of Land = Remainder of Water and Ice 
  6.3 Atmosphere Conditions 
  This section covers a planet atmosphere conditions and is broken down info Pressure, Radiation, 
  Toxicity, Average Surface Temperature and Climate Range.   Go through each of these steps, in 
  order shown, to determine each effect. 
  6.3.1: Atmospheric Pressure 
  This is the force exerted against a surface by the weight of the atmosphere. Thin 
  atmospheres are barely noticeable while dense atmospheres require special equipment 
  to withstand the pressure. Think of it as diving deep into the water, the further you go 
  the more pressure you feel on your skin.   Atmospheric pressure is determined by a 
  planet’s Mass and by some randomization: 
   
  Mass 
  1-2 
  3-8 
  9-0 
  Less than 0.3 
  Very Thin 
  Very Thin 
  Thin 
  .3 to .75 
  Very Thin 
  Thin 
  Moderate 
  .76 to 1.25 
  Thin 
  Moderate 
  Dense 
  1.26 to 10 
  Moderate 
  Dense 
  Very Dense 
  
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  Higher than 10 
  Dense 
  Very Dense 
  Very Dense 
   
  • 
  Very Thin 
  Anyone exposed to these types atmospheres will find it very difficult to breath 
  and must wear vacsuits or spacesuits with an oxygen supply.  Atmospheric 
  pressure is from negligible/vacuum up to .2 Galactic Standard Pressures.   
  o Use (1d100 * 0.02).   
  o If a character finds himself in this environment without a vacsuit or 
  spacesuit to equalize pressure, he’ll suffer from Major Environmental 
  Extremes (that is, 1d5 damage per minute and hourly rate of travel 
  divided by two).   
  o If the pressure is .05 or less, consider exposure to be Lethal 
  Environmental Extremes (that is, 1d5 damage per turn, and must make 
  an END check each turn or fall unconscious).   
  o Life cannot exist in planets with Very Thin atmospheric pressure. 
  • 
  Thin 
  Breathing is difficult but not impossible. Characters will have a difficult time 
  maintaining any extracurricular activity for more than a few minutes.  
  Atmospheric pressure is between 0.3 and 0.5 Galactic Standard Pressure.   
  o Use (1d10/50+0.3).   
  o If a character finds himself in the thin environment without breathing 
  assistance, he suffers from Mild Environmental Extremes (that is, -10 to 
  all actions and hourly rate of travel divided by two).   
  o If pressure is below 0.35 times the Galactic Standard Pressure, 
  characters would suffer from Moderate Environmental Extremes (that 
  is, 1d5 damage per hour of exposure and hourly rate of travel divided by 
  two).   
  o Life can exist on worlds with thin atmospheric pressure. 
  • 
  Moderate  
  Standard atmospheres that do not require any special gear to breath.  
  Atmospheric pressure is between 0.6 and 1.5 Galactic Standard Pressure.   
  o Use (1d10+5)/10.   
  o Life can exist on worlds with Moderate atmospheric pressure. 
  • 
  Dense 
  Breathing is difficult but not impossible. Characters will have a difficult time 
  maintaining any extracurricular activity for more than a few minutes.  
  Atmospheric pressure is between 1.6 and 16 times the Galactic Standard 
  Pressure.   
  o Use (1d100 x .16).   
  
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  o If a character finds himself in the dense environment without breathing 
  assistance, he suffers from Mild Environmental Extremes (that is, -10 to 
  all actions and hourly rate of travel divided by two).   
  o If pressure is above 12 times the Galactic Standard Pressure, characters 
  would suffer from Moderate Environmental Extremes (that is, 1d5 
  damage per hour of exposure and hourly rate of travel divided by two).   
  o Life can exist on worlds with Dense atmospheric pressure. 
  • 
  Very Dense 
  Anyone exposed to these types atmospheres will find it very difficult to breath 
  and must wear vacsuits or spacesuits with an oxygen supply.  Atmospheric 
  pressure is between 16 and 160 times the Galactic Standard Pressure.   
  o Use (1d100 x 16).   
  o If a character finds himself in this environment without a vacsuit or 
  spacesuit to equalize pressure, he’ll suffer from Major Environmental 
  Extremes (that is, 1d5 damage per minute and hourly rate of travel 
  divided by two).   
  o If the pressure is 100 or more, consider exposure to be Lethal 
  Environmental Extremes (that is, 1d5 damage per turn, and must make 
  an END check each turn or fall unconscious).   
  o Life cannot exist in planets with Very Dense atmospheric pressure. 
  Pressure 
  Vacsuit 
  Required 
  ? 
  Galactic 
  Standard  
  Pressure 
  Effect 
  Very Thin 
  Yes 
  1d100 x 0.02 
   
  Major: 1d5 damage per minute. Hourly Travel Rate/2 
  Lethal: (Pressure is 0.05 or less): 1d5 damage per turn, and must  
   
  make an END check each turn or fall unconscious. 
  Thin 
  n/a 
  (1d10/50)+0.3 
   
  Mild: -10 to all actions. Hourly Travel Rate/2 
  Moderate: (Pressure is below 0.35): 1d5 damage per hour.  
   
  Hourly Travel Rate/2 
  Moderate 
  n/a 
  (1d10+5)/10 
  n/a 
  Dense 
  n/a 
  1d100 x .16 
  Mild: -10 to all actions. Hourly Travel Rate/2 
  Moderate: (Pressure is more than 12): 1d5 damage per hour. 
   
  Hourly Travel Rate/2 
  Very Dense 
  Yes 
  1d100x6 
  Major: 1d5 damage per minute. Hourly Travel Rate/2 
  Lethal: (Pressure is more than 100): 1d5 damage per turn, and  
   
  make an END check each turn or fall unconscious. 
  6.3.2: Atmospheric Radiation Levels 
  Radiation can be deadly to complex and simple life forms alike, but most life can 
  tolerate some amount of it.    
  Proximity to the planet’s star determines base radiation exposure, but the planet can 
  vary this dramatically (the planet’s core can generate radiation, while its atmospheric 
  density – if it contains enough water – might act to reduce radiation exposure on the 
  planet’s surface).   
  
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  To determine radiation level, start with the planet’s proximity to the star (use the 
  colored proximity results from the zone distance table).  Use the Percentage of Liquid 
  (derived from Step 6.2) to cross reference against the atmospheric pressure column 
  determined from step 6.3.1. 
  6.3.2.1: Base Radiation Table 
  Proximity 
  Percentage 
  of Liquid 
  Very Thin 
  Atmospheric 
  Pressure 
  Thin 
  Atmospheric 
  Pressure 
  Moderate 
  Atmospheric 
  Pressure 
  Dense 
  Atmospheric 
  Pressure 
  Very Dense 
  Atmospheric 
  Pressure 
  Near 
  01-25 
  26-75 
  76-00 
  Lethal 
  Lethal 
  Lethal 
  Lethal 
  Lethal 
  Major 
  Lethal 
  Major 
  Moderate 
  Major 
  Moderate 
  Mild 
  Moderate 
  Mild 
  Low 
  Inner 
  01-25 
  26-75 
  76-00 
  Lethal 
  Lethal 
  Major 
  Lethal 
  Major 
  Moderate 
  Major 
  Moderate 
  Mild 
  Moderate 
  Mild 
  Low 
  Mild 
  Low 
  Low 
  Habitable 
  01-25 
  26-75 
  76-00 
  Lethal 
  Major 
  Moderate 
  Major 
  Moderate 
  Mild 
  Moderate 
  Mild 
  Low 
  Mild 
  Low 
  Low 
  Mild 
  Low 
  Low 
  Outer 
  01-25 
  26-75 
  76-00 
  Major 
  Moderate 
  Mild 
  Moderate 
  Mild 
  Low 
  Mild 
  Low 
  Low 
  Mild 
  Low 
  Low 
  Mild 
  Low 
  Low 
  Far 
  01-25 
  26-75 
  76-00 
  Moderate 
  Mild 
  Low 
  Mild 
  Low 
  Low 
  Moderate 
  Low 
  Low 
  Low 
  Low 
  Low 
  Low 
  Low 
  Low 
   
  Now that you have a base radiation level determined by proximity to the primary star of 
  the system, atmospheric pressure, and percentage of surface liquid, you can adjust it 
  based on a die roll on the table below (to determine base planetary core radioactivity). 
  Cross reference the value from table 6.3.2.1 and roll on the table below. 
  6.3.2.2: Adjusted Radiation Level 
  d10 
  Core Radioactivity 
  Low 
  Mild 
  Moderate 
  Major 
  Lethal 
  1 
  None 
  Low 
  Low 
  Low 
  Mild 
  Moderate 
  2-3 
  Some 
  Low 
  Low 
  Mild 
  Moderate 
  Major 
  4-7 
  Typical 
  Low 
  Mild 
  Moderate 
  Major 
  Lethal 
  8-9 
  Severe  
  Mild 
  Moderate 
  Major 
  Lethal 
  Lethal 
  10 
  Extreme 
  Moderate 
  Major 
  Lethal 
  Lethal 
  Lethal 
   
  • 
  Low 
  Planets with Low radiation either have a thick enough atmosphere to filter out 
  the radiation from the star, have very little water present in the atmosphere, 
  have lower core planetary radioactivity, or are far enough away from the 
  system’s star that radiation just isn’t a factor.   
  o Radiation can be expressed as 0.001 to 0.1 Galactic Standard Radiation 
  (use 1d100 * 0.001). 
  o There is no ill effect on characters exposed to this level of radiation. 
  o Life can exist on a planet with Low radiation exposure 
  • 
  Mild 
  Planets with mild radiation exposure experience some trace amount of 
  
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  radiation.  The atmosphere isn’t strong enough to filter all of it, or the planetary 
  core is generating it.  In either case, living characters can manage just fine.  The 
  galactic standard radiation exposure level falls within this category. 
  o Radiation can be expressed as 0.2 to 2.0 Galactic Standard Radiation 
  (use 2d10 * 0.1) 
  o Assume no ill effect on characters exposed to this level of radiation. 
  o Life can exist on a planet with Mild radiation exposure. 
  • 
  Moderate 
   Planets with moderate radiation exposure are being hit with more extremes.  
  Either it is in close proximity to its star or it lacks much water-based 
  atmosphere.  Such planets are hostile to biological things. 
  o Radiation can be expressed as 2 to 20 Galactic Standard Radiation (use 
  2d10) 
  o Assume characters exposed to this level of radiation without some type 
  of environmental or vacsuit become ill and suffer a radiation value of -
  10/10days (meaning, they have -10 to everything they do because of 
  illness, which continues for 10 days after exposure is done).  Although 
  not normally fatal, very long exposure or multiple many exposure hours 
  in a year might have more serious consequences (Referee’s choice). 
  o Life cannot exist unassisted on a planet with Moderate radiation 
  exposure. 
  • 
  Major 
  These planets are bombarded constantly with high levels of radiation.  Nothing 
  biological can last long. 
  o Radiation can be expressed as 20 to 200 Galactic Standard Radiation 
  (use 2d10x10) 
  o Assume characters exposed to this level of radiation without some level 
  of environmental or vacsuit become very ill and suffer a radiation value 
  of -20/20days (meaning, they have -20 to everything they do because of 
  this debilitating illness, which continues for 20 days after exposure is 
  done).  If exposure is too long, Referees can consider more permanent 
  damage effects. 
  o Life cannot exist unassisted on a planet with Major radiation exposure. 
  • 
  Lethal 
  The planet is a hot spot of radioactivity, deadly to all in, on, or around it. 
  o Radiation can be expressed as 200 or more Galactic Standard Radiation 
  (use 2d10x100) 
  o Assume characters exposed to even one turn at this level of radiation 
  without some level of environmental or vacsuit become very ill and 
  suffer a radiation value of -20/20days/fatal (meaning, they have -20 to 
  everything they do because of this debilitating illness, which continues 
  
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  for 20 days after exposure is done, and 20 days after initial exposure the 
  character dies).   
  o Life cannot exist unassisted on a planet with Lethal radiation exposure. 
   
   
  Radiation 
  Vacsuit 
  Galactic 
  Standard  
  Radiation 
  Effect 
  Low 
  Yes 
  1d100 * 0.001 
  There is no ill effect on characters exposed to this level of radiation. 
  Life can exist on a planet with Low radiation exposure 
  Mild 
  n/a 
  2d10 * 0.1 
  Assume no ill effect on characters exposed to this level of radiation. 
  Life can exist on a planet with Mild radiation exposure. 
  Moderate 
  Yes 
  2d10 
  Without a vacsuit characters become ill and suffer a radiation value 
  of -10/10days (meaning, they have -10 to everything they do 
  because of illness, which continues for 10 days after exposure is 
  done).  Although not normally fatal, very long exposure or multiple 
  many exposure hours in a year might have more serious 
  consequences (Referee’s choice). 
  Life cannot exist unassisted on a planet with Moderate radiation 
  exposure. 
  Major 
  Yes 
  2d10x10 
  Without a vacsuit become very ill and suffer a radiation value of -
  20/20days (meaning, they have -20 to everything they do because 
  of this debilitating illness, which continues for 20 days after 
  exposure is done).  If exposure is too long, Referees can consider 
  more permanent damage effects. 
  Life cannot exist unassisted on a planet with Major radiation 
  exposure 
  Lethal 
  Yes 
  2d10x100 
  Without a vacsuit become very ill and suffer a radiation value of -
  20/20days/fatal (meaning, they have -20 to everything they do 
  because of this debilitating illness, which continues for 20 days after 
  exposure is done, and 20 days after initial exposure the character 
  dies).   
  Life cannot exist unassisted on a planet with Lethal radiation 
  exposure. 
   
  6.3.3: Atmospheric Toxicity 
  The presence of an atmosphere does not guarantee that the air is breathable.  Roll 1d10 
  on the following table (refer to the Toxicity section of the core rules document for a 
  better understanding of the toxin ratings).  If toxins are present, arbitrarily assume they 
  are some combination of ammonia, chlorine, fluorine, hydrogen, methane, or some 
  other non-inert element: 
  1d10 
  Roll 
  Result 
  Toxin 
  1-2 
  No Toxicity 
  No danger from exposure 
  3-4 
  Trace Toxins 
  inhale/-10nausia/1minute 
  5-6 
  Moderate Toxins 
  inhale/1d10/1hour 
  7-8 
  Severe Toxins 
  inhale/1d10/3turns 
  9-0 
  Lethal Toxins 
  inhale/1d10/5turns/fatal 
  
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  6.3.4:  Average Surface Temperature 
  This represent the most common temperature found on the planet and is measured in 
  Celsius. The following text is guidelines to represent this value. 
   
   
  6.3.4.1: Base Temperature Table 
  Proximity 
  Very Dense 
  Atmospheric 
  Pressure 
  Dense 
  Atmospheric 
  Pressure 
  Moderate 
  Atmospheric 
  Pressure 
  Thin 
  Atmospheric 
  Pressure 
  Very Thin 
  Atmospheric 
  Pressure 
  Near 
  Inferno 
  Inferno 
  Hot 
  Hot 
  Moderate 
  Inner 
  Inferno 
  Hot 
  Hot 
  Hot 
  Moderate 
  Habitable 
  Hot 
  Moderate 
  Moderate 
  Moderate 
  Cold 
  Outer 
  Moderate 
  Cold 
  Cold 
  Cold 
  Frozen 
  Far 
  Moderate 
  Cold 
  Cold 
  Frozen 
  Frozen 
   
  • 
  Frozen 
  -100 to -200 degrees Celsius (use 1d100-200) 
  No life can exist at this temperature extreme. 
  • 
  Cold  
  -100 to 0 degrees Celsius (use 1d100-100) 
  Life can exist but only in certain areas 
  • 
  Moderate  
  0 to 20 degrees Celsius (use 1d100/5) 
  Planet’s average annual surface temperature is acceptable for life to thrive. 
  • 
  Hot 
  20 to 200 degrees Celsius (use 2d10x1d10) 
  Life can exist but only in certain areas. 
  • 
  Inferno 
  200 to 600 degrees Celsius (use  4d10x1d10+200) 
  No life can exist at this temperature. 
  6.4 Climate Range 
  Finally you can describe the climate ranges found on the planet.  Simply roll 1d10 and consult 
  the table below.  For instance, if you rolled a 6, you would record an axial tilt of (2d10) 18 
  degrees and would allow the average temperature to vary by +/-10 degrees Celsius. 
  d10 
  Axial Tilt 
  (in degrees) 
  Effect 
  Temperature Change For 
  Each Hemisphere 
  1-2 
  1d5-1 
  No significant seasons 
  0o  Celsius 
  3-4 
  1d10+5 
  Mild 
  -5 o /+5 o Celsius 
  5-6 
  1d10+15 
  Moderate 
  -10 o /+10 o Celsius 
  7-8 
  1d10+25 
  Strong 
  -15 o /+15 o Celsius 
  9-0 
  1d10+35 
  Extreme 
  -20 o /+20 o Celsius 
   
  
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  A planets axial tilt is the angle of inclination in relation to its orbital plane. The greater the tilt 
  the greater the seasonal effect on the planet. While one hemisphere is enjoying the summer 
  months the opposite will be cooler. The polar caps will also be affected by the tilt; “days” will 
  stretch out for months at a time while “nights” for the opposite polar cap will be in continuous 
  “night” 
   
   
   
   
   
   
   
   
   
  Climate Summaries: 
  You can, if desired, round out your planetary climate with a sentence or two defining anything 
  interesting.  Some options include: 
  • 
  Cool, frequent hurricane activity along the thirtieth parallel. 
  • 
  Temperate climate with violent hurricane activity along southern latitudes. 
  • 
  The planet has a completely temperate climate. 
  • 
  The planet is rainy and cold in the winter, rainy and hot in the summer. 
  • 
  A glacial planet that is slowly being terra-formed into a cool temperate planet. 
  • 
  Troubled by sweeping dust winds along the equator. 
  • 
  Tornados are common in the lowlands nearest the shores 
  • 
  Dark clouds with greenish coloration represent trace amounts of ionized copper 
  molecules often found in the upper atmosphere. 
  • 
  Planet is plagued by frequent hailstorms that form without warning 
  • 
  No cloud cover over land, lunar effect keeps cloud cover stationary over water. 
  Axial Tilt 
  
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  6.4: Length of Year 
  Determining how long a planet’s year is can be as easy as a lookup or as complicated as you would like it 
  to be.  Although both are simplified for game sake, you can use either of the following two optional 
  methods: 
  6.4.1: (option 1) Quick look-up 
  Using this method, the star is assumed to be a stellar classification of 2 with a code of “V”.  Therefore if 
  you rolled a type M star, it’s a M2-V star.  With this in mind, you can simply use the following lengths of 
  years (in Galactic Standard Days).  Note, however, that these represent mid-ranged values.  Your actual 
  length of year can vary.  For instance, if you rolled a habitable planet in the third zone of your G star, it 
  doesn’t have to have a length of year of exactly 420.  It can be above or below this number slightly, as 
  you see fit.   
  6.4.1.1: Quick Length of Year Table 
  Zone # 
  O 
  B 
  A 
  F 
  G 
  K 
  M 
  1 
  4,672 
  4,861 
  230 
  37 
  110 
  55 
  73 
  2 
  8,587 
  8,945 
  679 
  91 
  215 
  179 
  234 
  3 
  15,790 
  16,480 
  1,954 
  212 
  420 
  537 
  712 
  4 
  29,030 
  30,276 
  5,574 
  522 
  774 
  1,574 
  2,082 
  5 
  53,348 
  55,584 
  15,837 
  1,213 
  1,399 
  4,518 
  5,979 
  6 
  97,989 
  102,197 
  44,889 
  2,798 
  2,652 
  12,882 
  17,043 
  7 
  180,017 
  187,896 
  127,114 
  6,560 
  4,905 
  36,583 
  48,396 
  8 
  330,767 
  345,245 
  359,731 
  15,289 
  9,051 
  103,680 
   
  9 
  607,729 
  634,180 
  1,017,755 
  35,393 
  16,725 
  293,533 
   
  10 
  1,116,471 
  1,165,246 
  2,879,047 
  82,046 
  30,728 
  830,644 
   
  11 
  2,051,142 
  2,140,913 
  8,143,738 
  190,036 
  56,453 
   
   
  12 
  3,768,186 
  3,933,111 
  23,034,772 
  439,998 
  103,709 
   
   
  13 
  6,922,602 
  7,225,584 
   
   
   
   
   
  14 
  12,717,830 13,274,244 
   
   
   
   
   
  15 
  23,364,261 
   
   
   
   
   
   
  16 
  42,922,891 
   
   
   
   
   
   
    
  6.4.2: (option 2) Calculating Length of Year 
  Before you can actually calculate the length of year, you need to know the Stellar Mass of the star.  
  Simply look it up on the table below.  For instance, if you have a star of type G and roll a 2, then you 
  have a star of stellar class G2 with a Mass of 1.0. 
  Note that this table assumes all stars are in their main sequence (a code of V).  If you wish your star to 
  be older (weaker) or newer (more massive), the stellar mass will be different and the orbital zones 
  determined in Table 3.3 will differ dramatically.   
  
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  6.4.2.1: Stellar Mass Tables 
  Stellar  
  Class O 
   
  Stellar 
  Class B 
   
  Stellar 
  Class A 
   
  Stellar 
  Class F 
   
  Stellar 
  Class G 
   
  Stellar 
  Class K 
   
  Stellar 
  Class M 
  O0 
  100.0 
   
  B0 
  17.5 
   
  A0 
  2.9 
   
  F0 
  1.6 
   
  G0 
  1.1 
   
  K0 
  0.8 
   
  M0 
  0.5 
  O1 
  97.5 
   
  B1 
  14.2 
   
  A1 
  2.7 
   
  F1 
  1.6 
   
  G1 
  1.0 
   
  K1 
  0.8 
   
  M1 
  0.5 
  O2 
  95.0 
   
  B2 
  10.9 
   
  A2 
  2.5 
   
  F2 
  1.5 
   
  G2 
  1.0 
   
  K2 
  0.7 
   
  M2 
  0.4 
  O3 
  92.5 
   
  B3 
  7.6 
   
  A3 
  2.4 
   
  F3 
  1.5 
   
  G3 
  1.0 
   
  K3 
  0.7 
   
  M3 
  0.3 
  O4 
  90.0 
   
  B4 
  6.7 
   
  A4 
  2.1 
   
  F4 
  1.4 
   
  G4 
  0.9 
   
  K4 
  0.7 
   
  M4 
  0.3 
  O5 
  60.0 
   
  B5 
  5.9 
   
  A5 
  1.9 
   
  F5 
  1.4 
   
  G5 
  0.9 
   
  K5 
  0.7 
   
  M5 
  0.2 
  O6 
  37.0 
   
  B6 
  5.2 
   
  A6 
  1.8 
   
  F6 
  1.3 
   
  G6 
  0.9 
   
  K6 
  0.6 
   
  M6 
  0.2 
  O7 
  30.0 
   
  B7 
  4.5 
   
  A7 
  1.8 
   
  F7 
  1.3 
   
  G7 
  0.9 
   
  K7 
  0.6 
   
  M7 
  0.1 
  O8 
  23.0 
   
  B8 
  3.8 
   
  A8 
  1.8 
   
  F8 
  1.2 
   
  G8 
  0.8 
   
  K8 
  0.6 
   
  M8 
  0.1 
  O9 
  20.0 
   
  B9 
  3.4 
   
  A9 
  1.7 
   
  F9 
  1.1 
   
  G9 
  0.8 
   
  K9 
  0.5 
   
  M9 
  0.1 
   
   
  6.4.2.2: Calculate 
  Use the following simplified formula: 
   
  Where: 
  Y = Length of year (in Galactic Standard Days) 
  A = Distance from star (AUs determined in Table 3.3) 
  M = Mass of star (in Galactic Standard Stellar Masses. See table 6.4.2.1) 
   
  7: Example Star System 
  Now that you have read through the document lets roll up a system. 
   
  7.1: Number of Star 
   
  Roll d100, result is 41.  
  7.2: Type of Star 
  Roll d100, result is 47.   
  (Note the Number of Zones Modifier is +2) 
  7.3: Number of Zones 
   
  Roll d10 and add 2 results in 7. 
  Single 
  G 
  7 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
  Page 20 
   
  7.4: Zone Distance 
  We consult table 3.3 (Zone Distance Table) and cross reference our star. For each zone we pick a 
  value between the numbers shown. Note the habitable zone is number 3. 
    
   
  7.5: Astronomical Object 
  Now it’s time to populate each zone. We roll seven times on table 4.1. I rolled a Jovian for zone 
  1, which is always considered a gas giant (Hot Jovian). The next significant roll is zone 3, I rolled a 
  dwarf. Since this is the system habitable zone I decided to place a terrestrial planet in the zone. 
  In zone seven I rolled a binary planet. Rolling twice more I get terrestrial planets. I could choose 
  to two separate orbital paths within this zone which would be between 4.6 and 6.7 AU’s. Instead 
  I decided these planets will orbit each other.  Finally I use table 4.2 to define the asteroid belt. I 
  roll a 3 and 6; small asteroids that are moderately spaced.  
   
   
  7.6: Define the Astronomical Objects 
  Once we know what objects are in each zone we can define them by rolling on table 5.1 for each 
  planet or use table 5.2 if were in a hurry. In this example I will roll one planet using table 5.1 and 
  the rest (excluding the habitable zone) on table 5.2. 
  7.6.1: Creation Summary 
  Common Planetary Creation Summary: 
   
   
   
   
   
   
   
  Zone 
  1 
  2 
  3 
  4 
  5 
  6 
  7 
  AU 
  .5 
  .7 
  1.1 
  1.8 
  2.4 
  3.7 
  5.9, 6.3 
  Object Jovian, 
  Gas 
  Terrestrial Terrestrial 
  Asteroid Belt 
  (small, moderately  
  spaced) 
  Terrestrial Jovian (Binary) Terrestrial, Terrestrial 
  Gravity - Diameter – Mass 
  Table 5.1 or 5.2 
  Moons – Rings - Features 
  Table 5.3.1 
  Planetary Resources (optional)  
  Table 5.3.4 – Gas Giant Resources 
  Table 5.3.5 – Mineral Resources 
  Zone    1      2      3       4       5       6        7 
  AU       .5    .7     1.1   1.8    2.4    3.7     5.9 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
  Page 21 
   
  Detailed Planetary Creation Summary  
  (used for habitable planets, moons and terrestrials) 
   
   
   
   
   
   
   
   
   
   
   
  7.6.2: Planetary Statistics 
  Table 5.1 instructs which formulas to use for each planet type.  
  Zone 1 - Jovian, Gas 
  Gravity  
  4.05 
   
  I roll 81. (81 x .05) = 4.05 
  Diameter 
  7 
   
  I roll 4. (4+12) /4 = 7 
  Mass 
   
  198.45  
  7 * 7 * 4.05 = 198.45 
  Moons  
  I roll 9 and consult table 5.3.1 
   - Ancient ruins and remnants of ancient civilization that predates current cultures by 
  9,800 years are located on one of the moons. Additional I roll 47 moons and a single 
  ring.  
   
  Zone 2, 5, 6 and 7 
  Defining every planet in this system is not important to my campaign, so I will finish off 
  the rest of the zones (with the exception of the habitable zone) using tables in section 
  5.2 and recording them on the Star System Record Sheet. Remember Zone 4 is an 
  asteroid belt I rolled in section 7.5 
  Zone Gravity Diameter Mass #Moons 
  Day 
  Land Ice Liquid 
  Pressure 
  Toxicity 
  Axial Tilt 
  1(J) See 7.6.2  above 
   
   
   
   
   
   
   
   
   
  2(T) 
  0.8  
  0.73  
  0.42  
  1  
  11hrs 75%  12%  13%  Very Thin  
  Severely Toxic  
  40 deg 
  3(T) See 7.6.3  below 
   
   
   
   
   
   
   
   
   
  4(A) Asteroid  Belt 
   
   
   
   
   
   
   
   
   
  5(T) 
  1.0  
  2.00  
  4.00  
  --  
  248hrs 45%  19%  36%  Dense  
  Lethally Toxic  
  27 deg 
  6(J) 
  1.1 
  9.5 
  99.28 
  70 
  23hrs 
  % 
  % 
  % 
  Dense  
  Lethally Toxic 
  0 deg 
  7(T) 
  1.7  
  0.80  
  1.09  
  --  
  19hrs 15%  6%  
  79%  Moderate  
  Trace Toxins  
  32 deg 
  7(T) 
  1.0  
  0.73  
  0.53  
  2  
  32hrs 45%  4%  
  51%  Thin  
  Trace Toxins  
  19 deg 
  Length of Day 
  Table 6.1 
  Percentages of Land, Water and Ice 
  Section 6.2 
  Average Surface Temperature 
  Axial Tilt / Climate Range 
  Atmospheric Pressure 
  Atmospheric Radiation 
  Atmospheric Toxicity 
  Atmosphere Conditions 
  Table 6.3 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
  Page 22 
   
  * Zone 6 is a Jovian, Table 4.1 instructs us to roll a d10, even = Ice, odd = Gas. I roll 9, odd so we use the 
  Jovian gas table in section 5.2 
  Zone 2 
  This terrestrial planet is in the Near zone, (orange) of our G type star which tells us it’s 
  quite hot. The liquid and ice would have long since scorched off and the very thin 
  atmosphere could have been swept away by the stars solar wind. Nothing would be left 
  but a hot dust ball. Companies wishing to drill or exploit the planets natural resources 
  would need to consider protection.  
  Zone 5 
  The planets dense atmosphere is lethally toxic, most of the water has probably settled 
  to the lower atmosphere since the planet is in the OUTER zone and could possible be in 
  a semi-frozen state.  
  Zone 6 
  Typical Jovian gas giant.  
  Zone 7 
  Remember in section 7.5 I had decided to have one planet orbit the other? Interesting 
  eh? The planets are tidally locked, orbiting each other.  Huge craters can be found on 
  each planet, perhaps during the formation of this system they each had a separate 
  orbital path and somehow became locked in each others gravity well. If any moons were 
  present it would explain the huge craters littering the surfaces. The planets revolve on 
  the same plain, each planet eclipse the other.   
  7.6.2.1: Habitable Planetary Statistics 
  Zone 3 
  Terrestrial, Habitable  
  Here is where I do not want to pick the vales but let the dice roll them up. Note that I’m 
  not a slave to the dice, if the dice roll a value that would make the planet uninhabitable I 
  simply discard the roll and pick off the table. Let’s start rolling. 
   
  Common Planetary Statistics 
   
   
   
  Length of Day 
  I roll 3 – Fast length of day. Using the formula 2d10 hours I roll 12. 
   
  12 hours 
  Gravity  
  1.2 
  11.76m/s2 
  Diameter 
  1.79 
  22,315 km 
  Mass 
   
  3.84 
  2.2656E+25 kg 
  Moons  
  4 
  
  Star Systems Generator | Larry Moore 
  Revision: January 26, 2009 
   
   
   
   
   
   
  Page 23 
   
  Land Mass Percentage  
  Water – 41% 
  Ice – 15% 
  Land – 44% 
  The percentage of ice is a little high for the type of planet I want, so I reduce it to 5% 
  and use the reminder for land. 
   
   
  Atmospheric Pressure  
  I choose “Moderate” from table 6.3.1 and roll (1d10+5) /10 
   
  Atmospheric Radiation 
  Using table 6.3.2.1 we cross-reference the atmospheric pressure and percentage of 
  water; Mild. Table 6.3.2.2 instructs me to roll a d10, I get 1. Our planet has a Low 
  radiation level (1d100 * 0.001) 
   
   
  Atmospheric Toxicity 
  Since we want a habitable planet with no ill effects we ignore this table. 
  Average Surface Temperature 
  Cross-reference atmospheric pressure with the planets proximity; Moderate. (1d100/5) 
   
  Axial Tilt / Climate Range 
   
   
  Length of Year 
  I’m gong to use table 6.4.2.1 to determine the stellar mass which will effect the Length 
  of year. I see that the table shows 0 – 9 for each star type, that’s a d10 roll. I get 7. We 
  know now the star is a G7. Now let’s plug in the formula. 
   
  y =  365.25 x sqrt(1.1^3 /0.9) 
  Water – 41% 
  Ice – 5% 
  Land – 54% 
  0.8 kg/m2 
  0.012 mSv 
   8.4 degrees Celsius 
  4 degrees 
  No seasonal effects 
   444.18 Length of Year 
  
SOURCE: textdata/thevault/_GM Books/World Building & Game Design/ Misc S/Star System Generator (v2009-01-26).pdf