Study Challenges Assumption of Global Ocean Beneath Titan's Surface
New research suggests Saturn's moon Titan may have deep layers of ice and slush instead of a vast underground ocean, with potential pockets of liquid water.
Recent research indicates that Saturn's moon Titan may not possess a vast underground ocean as previously believed. Instead, the moon could contain deep layers of ice and slush, with pockets of melted water where life might potentially exist, according to scientists from NASA's Jet Propulsion Laboratory (JPL).
The study, published in the journal Nature, reexamined data from NASA's Cassini spacecraft, which orbited Saturn from 2004 to 2017. The findings suggest that Titan's interior comprises layers of ice, slush, and water extending over 340 miles deep. The outer ice shell is estimated to be about 100 miles thick, covering slush and liquid water layers that could reach depths of an additional 250 miles, with temperatures potentially as warm as 68 degrees Fahrenheit.
"There is strong justification for continued optimism regarding the potential for extraterrestrial life," said Baptiste Journaux of the University of Washington, a co-author of the study.
The research team, led by JPL's Flavio Petricca, analyzed Titan's response to Saturn's gravitational pull. Titan, being tidally locked, always shows the same face to Saturn. The gravitational interaction causes surface bulges up to 30 feet high. By measuring the timing between the peak gravitational force and the surface deformation, the team detected a 15-hour delay, suggesting an interior of slushy ice with pockets of liquid water, rather than a fully liquid ocean.
"If the moon held a wet ocean, the effect would be immediate," Petricca explained.
However, not all scientists are convinced by these findings. Luciano Iess of Sapienza University of Rome, whose earlier studies indicated a hidden ocean on Titan, expressed skepticism.
"At present, the available evidence looks certainly not sufficient to exclude Titan from the family of ocean worlds," Iess commented.
NASA's upcoming Dragonfly mission, set to launch later this decade, aims to further investigate Titan's composition and potential for life. The mission will deploy a rotorcraft to explore the moon's surface and subsurface.
Saturn has 274 known moons, with Titan being the second-largest in the solar system, slightly smaller than Jupiter's Ganymede. Other moons, such as Saturn's Enceladus and Jupiter's Europa, are also believed to harbor subsurface oceans and are considered prime candidates in the search for extraterrestrial life.
Cassini, launched in 1997, provided extensive data on Saturn and its moons before its mission concluded in 2017 with a deliberate descent into Saturn's atmosphere.