Origins of Material Diversity

The environments of space are astounding in their widespread diversity. One might intuitively assume that any particular local system should be relatively homogenous, given that fundamentally all objects within a given region are formed from mostly the same constituent components. Nevertheless, solar systems and their celestial bodies are highly diversified due to the chaotic nature of their formation and evolution.

The mechanisms by which variations arise begin during the planetary formation process. Planet-forming debris disks around stars are not homogeneous; the strength of the stars’ energy plays a key role in affecting the properties of basic elements. Different materials coalesce at different temperatures, and different compounds can be formed, torn apart, or blown outward, all based on the parent stars’ behavior and energy state. These materials then interact with each other in their own unique ways, introducing more variation and setting the stage for further emergent chaotic behavior.

Many resources of utilitous value cannot be synthesized, or at least not at economic scale. They can only be found naturally formed through exotic processes, which depend on the state of their past and present conditions. The potential for variety is unquantifiable - no solar system can represent a comprehensible fraction of what is possible.

Read more: Elemental Variants

Planetary Properties

A multitude of properties determine a world’s characteristics. Each property can affect the others, and will inherently change over its lifespan while maintaining a high sensitivity to its past and present conditions.

Temperature

Countless conditions affect the internal and external temperature of a planet. Surface temperatures are simultaneously a driven and driving property for other conditions. A solid or liquid core can affect whether a world retains a magnetic field, subterranean ocean, plate tectonics, volcanic activity, and many other properties.

Magnetic Field

A magnetic field is critical in repelling radiation from stars or gas giants, which has radical impacts on surface conditions and atmosphere. A fluidic core of magnetic matter is required for a magnetic field, which can be molten metals or other more exotic metallic liquids under superpressure in gas giant worlds. These magnetic fields can also have a significant impact on other nearby bodies like moons.

Subsurface Liquid

Subterranean liquids can vary from the liquid water of icy moons to the molten mantles of terrestrial worlds. These features keep afloat a crust of lesser density, the thickness of which may determine the type of tectonic activity. Thinner crusts will crack and fold at their seams, allowing for volcanic activity to redistribute heavier elements onto the surface. Thicker crusts hinder or outright prevent the formation of tectonic plates, the crust instead acting as a rigid uniform structure without volcanic breaks, putting further pressure on the underlying layers.

Maintaining atmosphere

A multitude of factors determine a world’s ability to retain an atmosphere. Foremost, the world must contain enough mass for its gravity to be able to hold onto the atmosphere. The pressure and density of normal gasses are determined by temperature; higher temperatures will cause an atmosphere to expand and be more easily lost to space, while colder atmospheres are kept closer to the surface. Solar wind is a hostile force emitted by stars which can strip away a world’s atmosphere over time; a magnetic field or distance from the source are required to limit this factor.

Mass and Gravity

Gravitational factors play important roles in planetary geology. Strong gravitational influences and resonances, particularly between the moons and parent of a planetary system, are able to shape the evolution of each other in unique ways. Tidal forces can have strong effects on internal temperature and tectonic stability, with even subtle variations having profound effects over time.