Conditions on Titan look more and more promising for life to exist. Now a substance has been found in its atmosphere that can serve as a material for the construction of cell membranes.
On Earth, all cell membranes are made of lipids, and the cells themselves are mostly water. On the largest moon of Saturn, conditions are terrible for earth cells. It is too cold for liquid water and the average surface temperature is -149 ° C. Seas there of liquid methane, in which the lipid membranes necessary for life on Earth simply could not develop.
But life on Titan may be composed of other substances. Dr. Maureen Palmer of NASA's Goddard Space Flight Center, along with colleagues, recorded traces of acrylonitrile in the nitrogen atmosphere of the satellite. According to a 2015 study, acrylonitrile is especially good for forming stable, flexible structures that are needed to build cell membranes.
Palmer says there is enough acrylonitrile on Titan to form 30 million cell membranes per cubic centimeter of fluid in one of the moon's largest seas. This means that there is a high probability that the membranes could grow enough to support more complex structures, such as the innards of the cell.
Titan's thick nitrogenous atmosphere and its methane seas are the best laboratory in the solar system for investigating the possible evolution of life completely alien to the one on Earth. “Titanium is a really attractive target for finding incredibly strange biochemistry and the boundaries of biochemistry itself,” says Palmer.
Nikolay Kudryavtsev