Illustration of Titan orbiting Saturn. (Image credit: NASA)
A new study has claimed that methane gas might be trapped beneath a 9.7-kilometre-thick distinct crust of Saturn's largest moon, Titan. The research team led by planetary scientists at the University of Hawaii observed that Titan's impact craters were hundreds of metres shallower than expected and that only 90 of them had been identified. The observations were surprising as based on data from other moons, additional impact craters that are much deeper should have been present on the surface of Titan.
"We realised something unique to Titan must be making them become shallower and disappear relatively quickly," said lead researcher Lauren Schurmeier, adding that the scientists turned to computer modelling to further the investigation.
"Using this modeling approach, we were able to constrain the methane clathrate crust thickness to five to ten kilometres [about 3 to 6 miles] because simulations using that thickness produced crater depths that best matched the observed craters," she added.
Titan could house life?
Methane clathrate, or "methane hydrate," is a solid compound in which a large amount of methane is trapped within the crystalline structure of water, creating a solid similar to ice. Scientists are of the view that studying Methane clathrate would help understand Titan's carbon cycle and its changing climate.
The thickness of the methane-rich crust could also suggest that Titan's interior was insulated, making the ice shell very warm and ductile, which implies it was slowly connecting. The convection indicated that biomarkers indicating life may have hoisted from Titan's subsurface ocean and carried to its outer icy shell, just awaiting discovery.
"If life exists in Titan's ocean under the thick ice shell, any signs of life, biomarkers, would need to be transported up Titan's ice shell to where we could more easily access or view them with future missions," Ms. Schurmeier added.
Notably, Earth's methane clathrate hydrates are found in the permafrost of Siberia and below the arctic seafloor.
Also read | Saturn's Rings To 'Disappear' In 2025. Will They Return? Read About It
Titan, the moon of the second-largest planet in our solar system is believed to be one of the most hospitable worlds. It is the only place other than Earth to have an atmosphere and liquids in the form of rivers, lakes and seas on the surface.
Moreover, Titan's nitrogen atmosphere is so dense that a human wouldn't need a pressure suit to walk around on the surface. However, an oxygen mask would be required for protection against frigid cold temperatures that hover around minus 179 Celsius.