There is a theory that life on Earth may have begun in freshwater hot springs environments, and there are scientists that think that just such a beginning for living organism may have begun the same way on Mars. Researchers are now looking at some 3.48-billion-year-old Australian rocks with biosignatures in the fossil record that might prove the theory to be true. If so, the discovery could help in the search for life, or at least the possible evidence of now extinct life on Mars.
Scientists in Australia have found ancient rocks in the Outback, according to NPR, that contain biological signatures and also indicate the presence of a hot spring. The finding appears to support the theory that Earth’s earliest life might have had its origin in freshwater hot springs on land — as opposed to originating in deep-sea hydrothermal vents.
University of New South Wales scientist Tara Djokic, who collected samples of the Australian rocks, which were found to be 600 million years older than any rock ever discovered, from the formation known as the Pilbara Craton, said the ancient stone was a “smoking gun,” pointing to the area as once being host to a volcanic hot springs system. The telltale was the the presence of geyserite, a mineral found only in a hot springs environment.
Scientists also uncovered what they referred to as “a suite of microbial biosignatures indicative of the earliest life on land.”
According to Djokic, the discovery was “a geological perspective saying actually, really early on we’re already seeing life on land. So it just lends weight potentially to an argument suggesting that the origin of life on land might be something to consider.”
The University of New South Wales scientist said the ancient rocks are so well preserved that researchers had no trouble observing multiple clear signs of life in a volcanic hot springs setting. The patterns found in the rock were “exactly what we see in modern hot springs. So it fits the bigger picture of these converging lines of evidence, and that’s what makes the argument in the case so strong.”
The findings could help in searching for the presence of life on Mars.
“If you’re going to look for life on Mars, we know it was preserved on hot springs here on the ancient earth,” Djokic said. “So there’s a good chance if it ever developed on Mars, then it would probably be preserved in hot springs there, too.”
With NASA currently looking into optimal sites to land its rover on the 2020 Mars Exploration Mission, Djokic noted that one of the sites under consideration was a “hot spring-type setting,” which had been found to be about the same age as early Earth.
Another site NASA has under consideration is the Hellas depression, which is home to an odd funnel surface depression that scientists believe might be caused by volcanic activity. A study released in November revealed that the depression might be similar to “ice cauldrons” on Earth, formations created when a volcano erupts under an ice sheet. Ice cauldrons on Mars could create an environment where warm liquid water and chemical nutrients might emerge to support life.
The search for life on Mars has been a disappointment for astrobiologists, although studies continue to support the possibility for living organisms to survive the harsh irradiated environment and the thin atmosphere. In January, astrobiologists at the Arkansas Center for Space and Planetary Sciences at the University of Arkansas in Fayetteville found that certain microbes could indeed survive the atmosphere on Mars. And in February, SETI (Search for ExtraTerrestrial Intelligence) Institute astrobiologist Janice Bishop revealed research that found that microbes could be using hematite, which is prevalent on the rocks of Mars, as a form of “sunscreen” coating to survive on the irradiated planet.
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