A locality is a region in the Astra that can support life. For convenience, localities are separated into classes that convey some fundamental characteristics of the region.
α class
An α class locality is located within the core of the Astra and is habitable enough to support tens of millions to billions of sentient beings. Examples of α classes include New Thessia and Orbits-Upon-Light.
β class
A β class locality is found on the inner half of a spiral arm and can support at least one self-sustaining society of sentient beings. Examples of β classes include Pilnik, Reshireshi, and Yan.
γ class
A γ class locality is found on the outer half of a spiral arm and cannot be actively hostile to the development of sentient life. Examples of γ classes include Vokon-B and Althane.
δ class
A δ class locality is located in the open space between arms. It must be habitable, but it need not have any native species. Examples of δ classes include The Inn at the End, Ghostwrit, and Archlight.
ε class
An ε class locality is — regardless of location — highly dangerous to the well-being of outsiders due to some unique property of the region. Entry into an ε class locality is forbidden for green observers and below. An example of an ε class is the Lifewell.
ζ class
A ζ class locality cannot be properly surveyed, and as such cannot be more accurately classified. An example of a ζ class is the Singularity.
ψ class
A ψ class locality doesn’t meet the population requirements imposed by the α, β, and γ classes but is located somewhere within the center or spiral arms of the Astra.