Hot springs in the icy, high-altitude expanses of Ladakh could be holding secrets from the very dawn of life on Earth and may even help in tracing the possible origins of life on Mars, besides providing valuable insights for India’s space exploration programmes.
A team of Indian scientists has made a breakthrough discovery that could not only rewrite our understanding of how life may have originated on Earth but also shed light on how astro-biological processes related to finding bio-signatures of life on other planetary bodies may have occurred.
Till date, Silica-based origin of life theories are proposed globally and role of carbonates, specifically calcium has been unexplored. Prior studies showed calcite, a compound of calcium, can catalyse prebiotic reactions in laboratory settings, according to the Ministry of Science and Technology. Prebiotic pertains to something existing or occurring before the emergence of life.
Scientists from Birbal Sahni Institute of Palaeosciences observed rapid carbonate precipitation in the environment of Puga valley, a high-altitude valley in south-eastern Ladakh that is known for its geothermal activity and hot springs.
The team, comprising Dr Amritpal Singh Chaddha, Dr Sunil Kumar Shukla, Dr Anupam Sharma, Prof MG Thakkar and Dr Kamlesh Kumar hypothesised that the extreme environment of Puga could act as a real-world prebiotic reactor and preservation site, and provide real world evidence of the phenomenon.
An interdisciplinary study, the team analysed the high-altitude hot spring calcium carbonate deposits (travertine) from Puga, situated at approximately 14,500 feet, using a combination of techniques based on inorganic and organic geochemistry including microscopy, gas chromatography, mass spectrometry, Raman, x-ray infrared and stable isotope geochemistry.
These revealed preserved amino acid derivatives, formamide, sulphur compounds and fatty acids encapsulated within calcite, supporting its role in concentrating and stabilising organic precursors.
“Empirical evidences suggest that the natural travertine from the Puga Hot Spring in Ladakh can trap and preserve prebiotic organic molecules, highlighting calcium carbonate as a potential natural template for origin-of-life chemistry under extreme Earth-like conditions,” Dr Chaddha, the study’s lead author said in a statement.
The study, published in ACS Earth and Space Chemistry, a peer reviewed American journal, provides a plausible mechanism of travertine formation and how organic molecules may have preserved and triggered life where there was presence of high UV in the early Earth environment.
“The findings provide insight into how life may have originated on Earth, aiding future planetary exploration (for example Mars). It could aid to ISROs future space exploration missions where identification of true biosignatures is required for identifying life and its associated biogeochemical process,” the ministry’s statement said.
It also enhances understanding of natural biomolecule preservation mechanisms, which may influence the development of new materials and life-detection technologies in astrobiology and synthetic biology, the statement added.
