Definition
A volcanic moon is a natural satellite whose interior retains enough energy to sustain active volcanism. This activity results from internal heat produced by radioactivity, tidal forces, or differentiation processes.
Structure
The structure consists of a central core, often metallic or rocky, surrounded by a partially molten mantle. A thin crust covers the surface and is pierced by numerous fractures and volcanic vents. The presence of magma chambers supports eruptions.
Volcanic Activity
Volcanism manifests through lava flows, gas fountains, deposits of sulfur, or molten ice depending on the chemical composition. The scale of eruptions can rapidly reshape the landscape, creating smooth plains, domes, or calderas.
Evolution
Over time, activity may intensify or weaken depending on the balance between heat production and energy loss. Tidal forces from the primary planet can sustain volcanism over long periods. When those forces diminish, the satellite tends to cool and activity decreases.
Limits
The existence of a volcanic moon depends on orbital state, initial composition, and thermal history. Not all moons exhibit such activity, and most are inactive or geologically solidified.