Scientists find moon of Saturn has chemical that could form ‘membranes’
NASA scientists have finally detected chemical acrylonitrile in the Saturn moon’s atmosphere of Titan, a place that has intrigued scientists investigating the chemical precursors of life.
Land, acrylonitrile, also known as the name of vinyl cyanide, is useful in the manufacture of plastics. In difficult conditions Saturn’s largest moon, it is believed that this chemical is capable of forming stable and flexible structures similar to cell membranes.
Other researchers have suggested that acrylonitrile is an ingredient in Titan’s atmosphere but has not reported unequivocal detection of the chemical in the heterogeneous mixture of organic or carbon-rich molecules found there.
Now, NASA researchers have identified the chemical imprint of acrylonitrile on Titan data collected by the Large / Matrix Atacama millimeter submillimetric (ALMA) in Chile. The team found large amounts of chemicals on Titan, probably in the stratosphere, the part of the misty atmosphere that gives the moon its orange-brown color.
“We have found convincing evidence that acrylonitrile is present in Titan’s atmosphere, and we believe that a significant amount of the raw material comes to the surface,” said Maureen Palmer, a scientist at the Goddard Center for Astrobiology at the Goddard Center for NASA space flight in Greenbelt, Maryland, and lead author of an article published on July 28, 2017 advances in science.
Earth’s plant and animal cells would not support much that Titan, where surface temperatures reach minus 290 degrees Fahrenheit (minus 179 degrees Celsius) and lakes border on liquid methane.
By 2015, university scientists have addressed the question of whether organic molecules could be on Titan could, under conditions that form structures, incompetent similar to the lipid bilayers of living cells on Earth.
Thin and flexible, the lipid bilayer is the main component of the cell membrane, which separates the inside of a cell from the outside world. The team identified acrylonitrile as the best candidate.
The researchers proposed that acrylonitrile molecules may come together as a sheet of material similar to a cell membrane. The sheet could form a hollow, microscopic sphere, which they called “azotosome”. This sphere could serve as a small container for storage and transport, such as spheres that can form lipid bilayers.
“The ability to form a stable membrane to separate the internal environment from the external is important because it provides a way to contain chemicals enough for them to interact,” said Michael Mumma, director of the Goddard Center for Astrobiology, which is funded By the Institute of Astrobiology of NASA.
“If similar membrane structures could have been formed by vinyl cyanide, it would be an important step in the path of life on Saturn’s moon Titan.”
Goddard team determined that acrylonitrile is abundant in Titan’s atmosphere, present in concentrations of up to 2.8 parts per billion. Chemistry is probably the most abundant in the stratosphere at an altitude of at least 125 miles (200 kilometers).