Titan methane lakes could form structures in the shape of life -like bubbles, say scientists
On December 25, 2004, the Huygens probe separated from the spacecraft Cassini and landed on the Sand surface of Titan. The probe survived for 72 hours on Saturn’s largest moon, revealing a world which is chemically complex and more similar to the earth than expected. For years, scientists have been intrigued by Titan as a foreign world which could have the right conditions to welcome life, although in a very different form from that on earth. New research from NASA reveals that molecular precursors in life could train in Titan’s methane lakes, allowing us a chance to learn how life is from and evolves in the universe.
In a recently published article by the International Journal of Astrobiology, a team of NASA researchers illustrates how vesicles, small compartments or bubble -shaped bags related to the membrane, could naturally form in the Titan lakes. It is believed that vesicles play a vital role in life training, an important step in the manufacture of precursors of living cells. The document examines how living conditions could evolve in an environment very different from the earth, highlighting our search for extraterrestrial life in the universe.
Titan is the only other world, apart from the earth, which is known to have liquid on its surface. But unlike the earth bodies of the earth, the lakes and the seas of Titan are not recommended for swimming, because they contain liquid hydrocarbons such as ethane and methane. Water is crucial for life as we know it, but what happens if Titan lakes have what it takes to host the molecules necessary for life to evolve?
The paper describes a process by which stable vesicles could form on Titan according to the data which has been collected so far on the atmosphere and the chemistry of the moon. On earth, molecules called amphiphiles have a divided personality, with a hydrophobic end (fearing water) and a hydrophilic end (which love water). In water, the molecules are naturally organized in spheres resembling a ball, resembling soap bubbles, by which the hydrophilic part turns outwards to interact with water while its hydrophobic counterpart breaks inside the sphere. This allows molecules to form complex structures and may have led to primitive cell membranes at the start of the earth.
On Titan, these vesicles could form thanks to the complex meteorological cycle of the moon, according to the article. The methane in the Titan atmosphere forms clouds, which rain on the surface to create river canals that fill the lakes and the seas of the moon. The liquid on the surface then evaporates to form clouds again. Researchers behind the new study suggest that the rain and sea surface droplets could be coated with layers of amphiphilia. When the droplets land on the surface of a pond, the two layers of amphiphiliacs meet to form a double layer vesicle. Over time, the vesicles would be dispersed throughout the pond and would compete in an evolutionary process which could lead to the formation of primitive protocels.
“The existence of all the vesicles on Titan would demonstrate an increase in order and complexity, which are the necessary conditions at the origin of life,” said Conor Nixon, researcher at the Goddard Space Flight Center and co-author of the new study. “We are delighted with these new ideas because they can open new directions in Titan research and change the way we are looking for life on Titan in the future.”
NASA is preparing to launch Dragonfly, the agency’s first titan mission in July 2028. The Rotorcraft landing will explore the surface of Saturn moon and will collect data on its atmosphere and geology. Dragonfly will help scientists better understand the bizarre world where life could train in very different conditions.
