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: 0.10 AU, 879K equilibrium
Habitability ScoreUninhabitable
0
Contributing Factors
water0
No water - the recipe has no hydrogen and oxygen to form it
geology40
Extreme volcanic activity may be hazardous
rotation10
Near tidally locked - one hemisphere perpetually scorched, other frozen, narrow habitable twilight zone only
Organic Chemistry20
Limited organic chemistry potential
atmosphere16
Atmosphere present but composition not ideal for life (partially stripped by slow rotation)
temperature0
Scorching - hot enough to melt lead, though rock stays solid; no chance for life (large moon stabilizes the axial tilt - steady seasons) (runaway tidal heating keeps the surface molten regardless of orbit)
magnetic Field100
Magnetic field provides radiation protection (a large close moon may help stir the core dynamo (speculative))
Physical Properties
Mass
2.50x Earth (1.49e+25 kg)
Radius
1.36x Earth (8,647 km)
Surface Gravity
1.36x Earth (13.3 m/s²)
Surface Temperature
879 K (606 °C / 1,123 °F)
Rotation Period
12.0 hours/day (faster than Earth)
Orbital Environment
Star Type
G-type (Yellow (Sun-like))
Distance from Star
0.10 AU (15 million km)
Orbital Period
12 days
Atmosphere
Volcanic outgassing - sulfur compounds and vaporized rock
Elemental Composition
O - Oxygen
23.0%
Si - Silicon
23.0%
Fe - Iron
17.2%
Surface Characteristics
Runaway tidal heating drives volcanism across a cold crust - lava lakes and sulfur plains between frozen plains
Merged with an adjacent moon: too close for both to hold a stable orbit.
Moon 2receding1.1% - 4.2 radii
Outside the synchronous orbit: slowly receding, like Luna (~cm per year).
Tidal braking locked the planet to its moon: one face forever moonward.
+5 temperature: large moon stabilizes the axial tilt - steady seasons-85 temperature: runaway tidal heating keeps the surface molten regardless of orbit+5 magneticField: a large close moon may help stir the core dynamo (speculative)