A team of researchers at Cornell University in Ithaca, N.Y., have modeled a new "methane-based, oxygen-free life form that can metabolize and reproduce similar to life on Earth," according to a press release from the university.
Why?
To create a template for a life form that can survive harsh cold - like the atmosphere on Saturn's moon, Titan. The oceans on Titan are not filled with water as we know it, but liquid methane.
The findings about the theorized cell membrane of organic nitrogen that can function in temperatures of 292 degrees below zero are published in the journal Science Advances. The research was led by chemical molecular dynamics expert Paulette Clancy, first author James Stevenson, a graduate student in chemical engineering and co-author Jonathan Lunine, director for Cornell's Center for Radiophysics and Space Research, according to the press release.
"We're not biologists, and we're not astronomers, but we had the right tools," Clancy said, according to the press release. "Perhaps it helped, because we didn't come in with any preconceptions about what should be in a membrane and what shouldn't. We just worked with the compounds that we knew were there and asked, 'If this was your palette, what can you make out of that?'"
Life on Earth is based on a strong, porous water-based housing called a liposome encapsulated by a phospholipid bilayer membrane. Typically, astronomers seek alien life in the circumstellar habitable zone - the area around the sun where liquid water (one oxygen and two hydrogen atoms combined by a covalent bond) can exist.
But what if "life" doesn't have the same definition elsewhere? What if life can be sustained at a much lower freezing point?
The theorized cell membrane is called "azotosome," which comes from the French word for nitrogen, "azote." The azotosome would consist of nitrogen, carbon and hydrogen molecules like those in the cryogenic seas of Titan, according to the press release.
The engineers then used a molecular dynamics method screening candidates from methane to be assembled into membrane-like structures. They found acrylonitrile azotosome to have stability, the ability to withstand decomposition and flexibility. Acrylonitrile a poisonous liquid organic used in the manufacture of acrylic fibers is already present in Titan's atmosphere.
Clancy said the next step is to demonstrate how the cells would act in the methane environment. Lunine looks forward to "someday sending a probe to float on the seas of this amazing moon and directly sampling the organics," according to the press release.
An essay written in 1962 about non-water-based life called "Not as We Know It," by science fiction writer Isaac Asimov, was part of Stevenson's inspiration, according to the press release.
Stevenson said, "Ours is the first concrete blueprint of life not as we know it."
