Evidence mounts against a deep water ocean inside Saturn’s moon Titan

Saturn’s biggest moon, Titan, might not have a hidden water body, more precisely, an ocean under its surface, according to a new study on the moon. 

On Wednesday, a new research paper was published in the journal Nature, suggesting that Titan has a significantly thick layer of ice deep beneath the surface, which is close to melting. 

This ice may be soft or slushy in its overall composition and could even contain small pockets of liquid water, but proving the presence of an entire ocean seems difficult. 

The group of researchers and scientists working on the project linked their observations with the loss of energy inside Titan. 

This study contradicts the suggestions made in the 2000s from the data obtained from NASA’s Cassini mission that Titan had a secret ocean beneath its cold surface.

Researchers recently reexamined the data and discovered new information about Saturn’s largest moon, indicating that it contains slushy ice instead of liquid water.

More details about the slushy ice observations on Titan, Saturn’s largest moon

Titan is known for its lakes and rain, which make it stand out from the other worlds in the solar system. However, unlike the lakes and rainfall on Earth, the ones occurring on Titan were comprised of methane and hydrocarbons.

It is mainly due to the extremely low temperatures that make it unfavorable for liquid water to exist.

In the 2000s, researchers suggested that Titan might be concealing a vast ocean based on the presence of water ice.

But the paper suggested otherwise, suspecting that the presence of an entire ocean underneath the icy surface of Titan is not probable. 

In a statement to Eureka Alert!, Baptiste Journaux from the University of Washington said:

“Instead of an open ocean like we have here on Earth, we’re probably looking at something more like Arctic sea ice or aquifers, which has implications for what type of life we might find, but also the availability of nutrients, energy, and so on.”

NASA led the research, whereas Journaux, assistant professor of Earth and space sciences at the University of Washington, and Ula Jones, a graduate student from the same university, worked on the project.

Titan moves around Saturn in an oval-shaped path, so the planet’s pull stretches the moon more at some times than others.

Researchers further discovered that the moon’s shape changed every 15 hours after Saturn’s strongest pull happened. 

Additionally, Titan loses much of the energy inside that it would if it had a large ocean under its surface, which is why experts needed a new theory – a new perspective to explain the feature.

“The degree of deformation depends on Titan’s interior surface. A deep ocean would permit the crust to flex more under Saturn’s gravitational pull, but if Titan were entirely frozen, it wouldn’t deform as much,” Journaux said.

While the observation might have aligned with the previous suggestion that Titan has a “global ocean,” researchers now had a different take on the Cassini mission data. 

This time around, the researchers focused on the timing of the shape change. They found out that Titan changes its shape about 15 hours after Saturn’s strongest pull on it.

They compared it to “stirring honey,” which required more energy to move, suggesting that the substance being moved was sticky and thick.

Consequently, when compared to the 15-hour delay in Titan, they deduced that the moon lost significantly more energy than it would if there were a watery liquid inside. 

As a result, they suspect that Titan holds a thicker and slushier icy layer rather than a liquid water ocean. 

“The discovery of a slushy layer on Titan also has exciting implications for the search for life beyond our solar system. It expands the range of environments we might consider habitable,” Jones said. 

In 2034, NASA will send a mission called Dragonfly to Titan to understand if the moon is suitable for habitation. 

Stay tuned for more updates.