Saturn’s largest moon Titan has long been of interest to scientists and astronomers who hoped to find signs of life there. However, the latest research conducted by astrobiologist Catherine Neish indicates the absence of life on Titan.
Neish and her team’s research suggests that Titan’s underground ocean is likely uninhabitable. The discovery has major implications for the search for extraterrestrial life in the outer solar system, where the giant planets Jupiter, Saturn, Uranus and Neptune are located.
Geosciences professor Catherine Neish notes that the scientific community had high hopes of finding life on the icy worlds of the outer solar system. However, new evidence suggests that this may be much less likely.
One of the key factors influencing the possibility of life existing is the availability of water. Life requires the presence of water as a solvent. Therefore, planets and moons with large amounts of water are of particular interest to scientists.
Titan’s underground ocean is believed to have a large volume of liquid water, more than 12 times the volume of Earth’s oceans. That is why Titan attracted the attention of planetary scientists and astronomers.
However, Neish and her team’s research showed that the amount of organic molecules that could be transported to Titan’s underground ocean is very small. Using data from impact craters and the estimated frequency of impacts on Titan’s surface, scientists determined that the mass of organic matter transported in this way is insufficient to support life.
One reason for this is the difficulty of transferring carbon from Titan’s surface to its underground ocean. Carbon is an essential element for life, and its presence along with water in one place is key to habitability.
However, icy worlds such as Titan, Europa and Ganymede contain virtually no carbon on their surfaces, and the amount of carbon in their depths remains unknown.
“We assumed that the majority of melt deposits — 65% — would sink all the way to the ocean,” Neish told Space.com. “Recent modeling work suggests that this is very likely an overestimate, but even in this most optimistic scenario, there is not enough organics moving into Titan’s ocean to support life there.”
For planetary scientists, astronomers and space agencies such as NASA, the discovery was a major disappointment. However, scientists hope that further research may shed light on other factors in the habitability of the outer solar system.