Editing Spheres (section)

== Nature of the Spheres ==

Each sphere is a fully formed planetary body with its own:

* gravitational conditions  
* atmosphere and climate  
* biosphere and ecological evolution  
* languages and cultures  
* political systems  

This diversity has produced radically different civilizations across the River. Some spheres resemble familiar terrestrial environments, while others possess strange atmospheric or ecological properties that shape the societies living upon them.

Because spheres developed largely in isolation before rediscovery by the gate network, their cultures often differ dramatically despite sharing access to the same transit system.