Cassini Data Shows Titan Lacks Global Subsurface Ocean

A new analysis of data from NASA's Cassini spacecraft has upended long-held assumptions about Saturn's largest moon, Titan, revealing that it likely lacks a vast subsurface ocean of liquid water. Instead, the moon harbors a deep layer of warm, slushy ice interspersed with pockets of melted water, potentially creating isolated environments conducive to microbial life, according to researchers who published their findings Wednesday in the journal Nature.

The study, led by Flavio Petricca, a planetary scientist at NASA's Jet Propulsion Laboratory, reexamined gravitational and radio signal measurements collected by Cassini during its 13-year mission around Saturn, which ended in 2017. For nearly two decades, scientists interpreted these observations as evidence of a global ocean buried beneath Titan's icy crust, based on how the moon deformed under Saturn's gravitational pull. The moon, the solar system's second-largest at about 5,150 kilometers across, is tidally locked, with one side always facing the ringed planet. This causes surface bulges up to 10 meters high when the bodies are closest.

However, inconsistencies in the data prompted Petricca's team to apply advanced processing...