Big World
Big Worlds are worlds that have a diameter in excess of 13,600 km.
- The term specifically relates to solid (rocky) planets.
- It describes a physical characteristic of the world.
Description / Specifications
Big World is a very broad term used to describe the general size of a world. A big world is likely to have a high surface gravity.
Big Worlds may be referred to as Superterran Worlds. This term is sometimes applied only to worlds of Size Code B or more, to differentiate them from worlds that can be created by normal (unmodified) world generation processes.
General size code categories:
- Size Codes 0 or S: Planetoid.
- Size Codes 1-3: Small World.
- Size Codes 4-8: Meso World.
- Size Code 9 or more: Big World.
Planetary Characteristics
General details for big worlds are provided below:
Worlds may be up to 800 km smaller or 800 km larger than the mean diameter and still qualify as the same UWP size code.
Terra, the human homeworld, has an average density of 5.5 grams per cubic centimeter (abbreviated to 5.5 g/cm³).
- Low density worlds largely consist of stony materials. They have relatively low quantities of heavier elements such as iron within their structure.
- Average density worlds have moderate amounts of heavier elements within their structure.
- High density worlds have greater quantities of heavier elements within their structure.
| Size Code |
Mean Diameter |
Low Density (3.5 g/cm³) |
Average Density (5.5 g/cm³) |
High Density (7.5 g/cm³) |
Distance to Horizon |
|---|---|---|---|---|---|
| 9 | 14,400 km | Mass: 0.885 Earths Surface Gravity: 0.710 G |
Mass: 1.425 Earths Surface Gravity: 1.125 G |
Mass: 1.940 Earths Surface Gravity: 1.535 G |
Approximately 5.4 km |
| A (10) | 16,000 km | Mass: 1.210 Earths Surface Gravity: 0.790 G |
Mass: 1.955 Earths Surface Gravity: 1.250 G |
Mass: 2.665 Earths Surface Gravity: 1.700 G |
Approximately 5.7 km |
| B (11) | 17,600 km | Mass: 1.610 Earths Surface Gravity: 0.870 G |
Mass: 2.560 Earths Surface Gravity: 1.375 G |
Mass: 3.545 Earths Surface Gravity: 1.875 G |
Approximately 6.0 km |
| C (12) | 19,200 km | Mass: 2.095 Earths Surface Gravity: 0.945 G |
Mass: 3.375 Earths Surface Gravity: 1.500 G |
Mass: 4.605 Earths Surface Gravity: 2.045 G |
Approximately 6.3 km |
| D (13) | 20,800 km | Mass: 2.660 Earths Surface Gravity: 1.025 G |
Mass: 4.290 Earths Surface Gravity: 1.625 G |
Mass: 5.855 Earths Surface Gravity: 2.215 G |
Approximately 6.6 km |
| E (14) | 22,400 km | Mass: 3.325 Earths Surface Gravity: 1.105 G |
Mass: 5.360 Earths Surface Gravity: 1.750 G |
Mass: 7.310 Earths Surface Gravity: 2.385 G |
Approximately 6.9 km |
| F (15) | 24,000 km | Mass: 4.085 Earths Surface Gravity: 1.180 G |
Mass: 6.590 Earths Surface Gravity: 1.875 G |
Mass: 8.990 Earths Surface Gravity: 2.560 G |
Approximately 7.2 km |
| G (16) | 25,600 km | Mass: 4.960 Earths Surface Gravity: 1.260 G |
Mass: 8.000 Earths Surface Gravity: 2.000 G |
Mass: 10.91 Earths Surface Gravity: 2.730 G |
Approximately 7.5 km |
| H (17) | 27,200 km | Mass: 5.950 Earths Surface Gravity: 1.340 G |
Mass: 9.955 Earths Surface Gravity: 2.125 G |
Mass: 13.09 Earths Surface Gravity: 2.900 G |
Approximately 7.8 km |
| J (18) | 28,800 km | Mass: 7.065 Earths Surface Gravity: 1.420 G |
Mass: 11.39 Earths Surface Gravity: 2.250 G |
Mass: 15.38 Earths Surface Gravity: 3.040 G |
Approximately 8.1 km |
| K (19) | 30,400 km | Mass: 8.305 Earths Surface Gravity: 1.495 G |
Mass: 13.40 Earths Surface Gravity: 2.375 G |
Mass: 18.09 Earths Surface Gravity: 3.207 G |
Approximately 8.4 km |
Note that different versions of the rules may have alternative definitions for Small Worlds, Meso Worlds, and Big Worlds.
Electron Degeneracy
Worlds that have masses in excess of 10 earths are so massive that their physical structure experiences electron degeneracy: their enormous gravitational pull and the intense pressures acting on the world crush the molecules that make them up to such an extreme degree that their electrons cannot move freely.
- Extremely large Big Worlds may be sources of naturally occurring superdense materials.
History & Background / Dossier
Larger Big Worlds may be substantially more massive than small gas giants, and can have greater diameters.
Big worlds almost always retain an atmosphere of some kind. Often it is a variety of exotic atmosphere, ranging from a chemically peculiar mixture to a high pressure cauldron of toxic substances.
Probable Orbits
Big Worlds may be located within any region of a system. Big worlds are rarely moons of larger worlds.
Occasionally, the designated mainworld in a system may orbit a big world as its primary world.
References & Contributors / Sources
|
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- Marc Miller. Worlds and Adventures (Game Designers Workshop, 1977), .Marc Miller, Robert Eaglestone, Don McKinney. Worlds and Adventures (Far Future Enterprises, 2019), .
- Marc Miller. Scouts (Game Designers Workshop, 1983), .
- Geir Lanesskog. World Builder's Handbook (Mongoose Publishing, 2023), .Joe Fugate, J. Andrew Keith, Gary L. Thomas. World Builder's Handbook (Digest Group Publications, 1989), .
- Terrance McInnes, Dave Nilsen. World Tamer's Handbook (Game Designers Workshop, 1994), .
- Marc Miller. T5 Core Rules (Far Future Enterprises, 2013), .
- Martin Dougherty. A Guide to Star Systems (Mongoose Publishing, 2015), .
- Matthew Sprange. "Gas Giants, Planetoid, and other bodies." Journal of the Travellers' Aid Society volume 2 (2019): 80-85.
- Martin Dougherty. Referee's Handbook (Mongoose Publishing, 2021), 83-84.
- External Link: Beowolf's Libary Data Website dead link (relevance pending, as site has not been archived)
- Author & Contributor: Lord (Marquis) and Master Scout Emeritus Adie Alegoric Stewart of the IISS
- Author & Contributor: Lord (Marquis) and Master of Sophontology Maksim-Smelchak of the Ministry of Science