Salt water and organic molecules on Enceladus: a step closer to finding signs of life
Recent NASA-funded research has provided new insights into the behavior of organic molecules frozen in salt water, an environment that mimics conditions on Saturn's moon Enceladus. These results will help astrobiologists better understand how habitable Enceladus's subsurface ocean may be, and could be used in the future to design missions aimed at searching for signs of life on icy planets.
Enceladus is one of the main objects of research in the field of astrobiology. In 2005, NASA's Cassini spacecraft observed material ejecting from cracks near the moon's south pole. Since then, astrobiologists have been trying to gain insight into the composition and conditions of Enceladus' subsurface ocean.
Data collected by Cassini showed that the ejected matter contained salts and organic matter containing carbon and hydrogen. Among them are many molecules that are an important part of living cells. The new study focused specifically on two such molecules: glycine and aspartic acid, which are amino acids.
Scientists studied how these molecules behave when rapidly frozen in salt water. The results indicate that ice particles containing large amounts of salts may contribute to the concentration of organic molecules. This can be a useful fact when searching for specific organic molecules that may be signs of life.
“Some organic molecules can be signs of life, so it is important to understand which molecules to look for and how they are distributed to assess the habitability of an environment. NASA has historically followed the “follow the water” approach in the search for life, but our findings suggest it may also be worth “following the salt,” said study co-author Morgan Cable of NASA Jet Propulsion Laboratory (JPL).