Titan's rivers flow with methane, not water
Titan hosts a methane-driven hydrological cycle: methane rain feeds rivers and lakes of methane and ethane, while surface water remains frozen as rock. Its frigid, nitrogen-rich atmosphere and −179°C surface temperature let methane act like water, with radar and Huygens data showing branching channels and lakebeds carved by hydrocarbons. The largest seas lie near the north pole, while equatorial regions host organic dunes. Titan may conceal a subsurface water ocean, and methane replenishment remains an open question. NASA's Dragonfly mission will explore Titan's dunes to study organic chemistry and habitability.
