Methane-based, oxygen-free aliens may exist on Saturn's moon Titan

Washington: Researchers have revealed that Saturn's moon, Titan, could host methane-based and oxygen-free life form.

A new type of methane-based, oxygen-free life form that can metabolize and reproduce similar to life on Earth has been modeled by a team of Cornell University researchers.

Taking a simultaneously imaginative and rigidly scientific view, chemical engineers and astronomers offer a template for life that could thrive in a harsh, cold world - specifically Titan, the giant moon of Saturn. A planetary body awash with seas not of water, but of liquid methane, Titan could harbor methane-based, oxygen-free cells.

Albeit hypothetical, the cell membrane, which has been made up of small organic nitrogen compounds, was able to function in extremely cold liquid methane temperatures, a necessity for worlds with harsh and cold environments such as the Titan, Saturn's giant moon, which could harbor methane-based and oxygen-free cells and has seas made of liquid methane.

The cell membrane is dubbed "azotosome." "Azote" is the French word for nitrogen. "Liposomes," on the other hand, is hailed from the Greek words "lipos" and "soma," which mean "lipid body" and thus "azotosome" means "nitrogen body." Azotosome was composed of carbon, nitrogen and hydrogen molecules known to exist in the cold seas of Titan but exhibit the same flexibility and stability of the analogous liposome on Earth.

Many astronomers look for signs of life in extraterrestrial worlds in the so-called circumstellar habitable zone, where liquid water can exist, basically because life on Earth is based on phospholipid bilayer membrane, the water-based vesicle, where the organic matter of each cell is housed. Researchers are exploring the idea of cells that are not based on water but on methane and have very low freezing point.

With the initial proof of concept on hand, the researchers said that the next step would be to try to demonstrate how the cells would behave in a methane environment to see what would be equivalent to metabolism and reproduction in oxygen-free, methane-based cells.

The study is published in Science Advances.