Why is this a Volcanic World?Runaway tidal heating from its moons drives volcanism across a cold crust - the planet is kneaded like Io.
Resonant, close-in moons pump orbital eccentricity, and the resulting tidal flexing dissipates enormous heat in the interior. Only a fraction of the surface is molten at once, so the ground between the vents stays as cold as the orbit allows - Io's own equilibrium temperature is about 110 K.
Classification Criteria:
✓ Close-in moons in a resonant configuration✓ Tidal heat flux beyond the runaway threshold- The orbit is not what melted it: 1.46 AU, 230K equilibrium
Habitability
Destroyed — no longer habitable
Physical Properties
Mass
0.20x Earth (1.19e+24 kg)
Radius
0.58x Earth (3,726 km)
Surface Gravity
0.58x Earth (5.7 m/s²)
Surface Temperature
230 K (-43 °C / -46 °F)
Rotation Period
1.0 hours/day (faster than Earth)
Orbital Environment
Star Type
G-type (Yellow (Sun-like))
Distance from Star
1.46 AU (218 million km)
Orbital Period
1.76 years
Atmosphere
Volcanic outgassing - sulfur compounds and vaporized rock
Elemental Composition
Si - Silicon
16.7%
U - Uranium
14.3%
N - Nitrogen
7.1%
Surface Characteristics
Runaway tidal heating drives volcanism across a cold crust - lava lakes and sulfur plains between frozen plains