“In science fiction, there is a lot of effort put into searching for signs of life like plants, animals and organisms that look like us. But there is a higher probability that alien life will be at the microscopic level,” says Rutgers University geochemist, Nathan Yee, co-investigator at the NASA-funded ENIGMA project that’s researching how proteins, “sophisticated nanomachines,” evolved to create life on earth. “That fact is so much more interesting when you consider what the earliest lifeforms on Earth were capable of doing.”
Life is Electric
The ENIGMA project (Evolution of Nanomachines In Geospheres and Microbial Ancestors) explores the catalysis of electron transfer reactions by prebiotic peptides to microbial ancestral enzymes to modern nanomachines, integrated over four and a half billion years of Earth’s changing geosphere. Currently, very little is known about the origin of these proteins on Earth or their evolution in early microbial life.
“All things eat and breathe, and when you remove oxygen, like on ancient-Earth or Mars atmospheres, there are microbes that have figured out ways to breathe other things, like iron found inside of rocks,” he said.
NASA wanted someone with expertise about microbes interacting with minerals and the biosignatures that ancient Earth microbes left behind in rocks after they died and went extinct, which happens to be my area of expertise, Yee said.
Searching for building blocks of life on other planets and moons
“Everywhere there is liquid water on Earth, we’ve found microbial life. We are smart enough to know that if a world has oceans, then we should look there for alien microbes. Europa, which is one of Jupiter’s moons, has what appears to be global oceans under sheets of ice. Saturn’s moon Enceladus has geysers and hot springs spewing from its south pole,” Yee said, explaining that in our search to find extraterrestrial life, the focus should be not on planets, but rather on moons in our galaxy where there’s evidence of water.
“That points to the possibility of volcanoes and hydrothermal vents, which on Earth harbor ancient life forms and may have contributed to the origin of life here. Now, do I think there’s going to be a whale on these moons? Likely not, but it is possible that alien microbes have evolved and continue to live there,” Yee concluded.
The Daily Galaxy, Andy Johnson, via Rutgers University
Image credit: Researchers created an enhanced view of Saturn’s ocean-moon, Enceladus’ south polar region by combining Cassini images taken through infrared, green, and ultraviolet filters. The tiger stripe fractures, the source of the plumes venting gas and dust into space, are prominently visible at center. NASA/JPL-Caltech/SSI/Lunar and Planetary Institute/Paul Schenk (LPI, Houston)