A team of researchers fromNational Institute of Geophysics and Volcanology (INGV), in collaboration with the Institute of Polar Sciences of the CNR (CNR-ISP), the Institute for Water Research of the CNR (CNR-IRSA), the Institute of Geosciences and Earth Resources of the CNR, the Institute for Applications of Computing “Mauro Picone” of the CNR (IAC-CNR), the Department of Earth Sciences of the University “La Sapienza” of Rome, the University of Florence, the Southern Illinois University (USA), the Queen's University of Belfast (Ireland) has made a significant discovery concerning Lake Enigma (Antarctica).
The study, recently published in the journal Communications Earth & Environment, highlights how researchers have located, contrary to what was supposed until now, a layer of fresh water permanently covered by a thick layer of ice. This very particular habitat is the result of a unique and unusually diverse ecosystem of microorganisms. This type of lake can host a wide variety of microbial life, which represents the dominant form of life present in Antarctic lakes. The ENIGMA project, a research project funded by the National Antarctic Research Program (PNRA) and coordinated by Stefano Urbini of the INGV, takes its name from the lake of the same name located about 5 km from the Italian Mario Zucchelli base. Lake ENIGMA is so called because of the enigmatic presence of a raised debris cone in its center and believed to be completely frozen since 1989.
Radar surveys conducted by INGV researchers between November 2019 and January 2020 revealed the presence of liquid water under a layer of ice that can be more than 14 meters thick. The lake was then drilled and explored firsthand with an underwater camera that provided researchers with previously unseen images. Microbiologists from the National Research Council (Institute of Polar Sciences) involved in the project identified several types of microbial mats (films composed of microbial colonies), some up to 40 centimeters high and 60 centimeters in diameter. DNA analyses performed on water samples identified the composition of the microbial ecosystem, revealing a high quantity of Patescibacteria bacteria, which have an average diameter of 200-350 millionths of a millimeter. Until now, this type of bacteria had never been found in similar Antarctic lakes and their role (symbiotic or predatory) is still completely unclear.
This type of study and discovery offers new insights from both a “terrestrial” and “extra-terrestrial” perspective. This type of habitat where “extremophilic” organisms can survive or proliferate is in fact possible in other similar environments.
Just think of Europe, one of the natural satellites of Jupiter, or to Enceladus (a moon of Saturn) where, beneath their ice caps, it is considered highly probable that habitats similar to those of Lake Enigma exist and which could therefore contain extraterrestrial (microbial) life forms.
Further information in the article published on the INGVambiente Blog
