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Mapcraft - Fantasy map designer

WorldGen - SciFi universe generator

Mapcraft Web - Web based fantasy map designer

All code for the project is released under the GPL, and is copyright Samuel Penn.

The text on this wiki is dual licensed CC-BY-SA and GPL.

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Dwarf Terrestrial Group

Small worlds with masses ranging from 0.0001 to 0.15 Earth masses. Most are large enough to sustain hydrostatic equilibrium (they are spherical), and may have geological activity due to tidal stresses. Many are relatively passive worlds though, and rarely have much of a sustainable atmosphere.

Protothermic Class

Small bodies still in the process of forming. Their surfaces are often partial to completely molten, and their atmospheres are typically thick with hydrogen and helium. They are generally found in young solar systems.

GeoPassive Class

Such worlds do not sustain continuous geological activity. Their surfaces are largely unchanged since their formation.

GeoThermic Class

These worlds sustain regular or intermittent geological or geothermal activity due to temperature differences caused by highly eccentric orbits.


These worlds sustain geological activity due to tidal flexing. The level of activity can range from constant resurfacing to intermittent geothermal activity, such as cryo-volanic outgassing.


GeoCyclic worlds possess an active geology which occurs in a cyclic basis, often over periods of hundreds of millions of years. Though various mechanisms may be responsible, this is often caused by a slow build up of geothermal energy which results in a short phase of activity.

pcl/dwarf_terrestrial_group.txt · Last modified: 2017/11/19 22:32 by sam