If life can find a way to flourish in the deepest oceans of the Earth, what prevents it from existing elsewhere in the cosmos?
This is a question that astrobiologists at NASA's Jet Propulsion Laboratory (JPL) are trying to answer. They are also faced with the idea that they reproduced the conditions of the deep ocean in the laboratory, discovering that the building blocks of life actually formed at the bottom of the ocean. about 4 billion years ago.
Sunlight can not penetrate miles of water to reach the bottom of the ocean, making it a remarkably cold and completely black place. But around the hydrothermal vents – openings in the bottom of the ocean that spit water and heated materials into the earth's crust – scientists continue to discover bustling metropolises, teeming with organism-rich organisms. Deep waters. Aeration vents are a place where life does not need sunlight to survive. Instead, she can feed off a buffet of chemicals that form in bubbling black fireplaces that come out of the bottom of the ocean.
"As a researcher on hydrothermal vents on the high seas, I think the hypothesis that life-formed air sources is the best we have at the present time," says Lucy Stewart, marine science microbiologist at GNS Science, New Zealand.
The astrobiologists of the JPL, led by Laurie Barge, thought in the same direction. To examine this dilemma, they duplicated deep ocean conditions in standard laboratory cups, helping to understand how life could have knotted slowly at the beginning of the Earth.
The team produced its own Young-Earth-Ocean-In-A-Glass glass, containing water, minerals, and the ammonia and pyruvate molecules that are typically found near hydrothermal vents and are considered as precursors of the constituent elements of life. Heating the mixture to 70 degrees Celsius (158 degrees Fahrenheit) and reducing the oxygen content of this mixture has provided them with a laboratory model of "primordial ocean" conditions.
Their findings, published in the journal Proceedings of the National Academy of Sciences on February 25, show that their hydrothermal mouths built in the laboratory are places where the constituent elements of life, amino acids, can be formed.
In the early terrestrial aquarium, a notable amino acid was produced: alanine. The molecule is considered extremely important in the synthesis of proteins, which fill a dizzying range of normal functions in organisms, from bacteria to humans. The team also discovered lactate, which some scientists believe could also be a precursor molecule that allows life to flourish.
"We have shown that under geological conditions similar to those of the Earth and perhaps to other planets, we can form amino acids and alpha-hydroxy acids from a simple reaction in sweet conditions that would have existed at the bottom of the sea, "said Barge.
It's important to note that the NASA research team did not create the "life" itself in this experiment – but it showed how the building blocks to become life can arise in the deep ocean around these vents.
"Life-history researchers are still understanding all the many steps between" simple organic compounds "and" living organisms, "Stewart said. "Knowing how they can be created at a hydrothermal vent is an extra step to understanding how the entire biogenesis process could have unfolded 4 billion years ago."
Follow-up studies will continue to survey their laboratory-grown ocean to search for other potential amino acids and precursor molecules.
The results of the team provide a foundation upon which other researchers can build to best choose the places in the cosmos that could be life-giving. They already feel satisfied with some interplanetary sites. For example, Enceladus, the sixth largest moon of Saturn, is an icy marble of a world covered with a thick layer of ice. Scientists haveand believe that the oceans beneath its frozen exterior could also harbor hydrothermal vents.
"Understanding the conditions necessary for the origin of life can help to narrow the places where we think life could exist," said Barge.
This gives hope that there may be hidden life in our own backyard. I mean, if we can create the building blocks in a glass beaker in Pasadena, California, life may also be able to find a way to hide under the ice of a distant moon.
Originally published on February 25 at 16:31. PT.
Updated at 17:54 PT: Added comments from Lucy Stewart.