NASA Mars rover Spirit may have stumbled upon what is now believed to be possible evidence of biological activity on the Red Planet, a new study based on discovery in Chile suggests.
Arizona State University geo-scientists have published a paper in Nature Communications wherein they have revealed the discovery of fingerlike structures that form in the hot spring deposits by processes that combine biological and non-biological activity in Chine and these structures are very similar to what Mars rover Spirit spotted rich deposit of pure silica surrounded by outcrops also rich in silica while exploring next to an eroded deposit of volcanic ash dubbed Home Plate in the Columbia Hills of Gusev Crater on Mars.
According to researchers the Chilean hot springs are at a place called El Tatio and lie at the edge of the extremely dry Atacama Desert, one of the best “Mars analog” sites on Earth. The team behind the study is of the opinion that El Tatio produces silica deposits with structures influenced by living organisms that appear nearly identical to those found eight years ago by Spirit in Gusev Crater on Mars.
The primary question that arises now is whether the rich deposits of silica found on Mars by Spirit were influenced by life or not? Scientists at ASU believe that with so many years of Mars exploration now we at a stage that will enable us to start looking for “biosignatures” – naturally occurring traces that indicate the presence of life, either today or in the past.
With scientists having found countless biosignature of past life through fossils on Earth, there is enough knowledge at our disposal that could enable us to detect and find biosignatures on Mars as well. However, the primary challenge is that none of the rovers on Mars has found any fossils yet and this would force scientists to look for more clues including physical structures such as compacted mats of microorganisms called stromatolites, found in various environments on Earth.
If we come back to Earth, the hot springs are among the highest known active thermal springs on Earth (over 14,000 feet). At night, even in summer, temperatures at El Tatio often drop below freezing, and by day lots of ultraviolet light from the Sun comes through the thin, dry air. This makes El Tatio probably the best terrestrial analog for ancient Martian hot springs. Scientists have found that conditions at El Tatio produce silica deposits with characteristics that are among the most Mars-like of any silica deposits on Earth.
These characteristics compare favorably with the Martian Home Plate silica outcrops and because microbes play a versy important role in producing the distinctive silica structures at El Tatio, there is a possibility that the Martian silica structures formed in a comparable manner – in other words with the help of some form of biological entity that was present at the time.