Scientists have confirmed that liquid water exists in an underwater lake, allowing humans to further explore Mars. Using radar data collected from an orbiting spacecraft between 2012 and 2015, they identified a lake sitting about 1.6 km under the planet’s surface, with a 19 km-wide stretch of liquid. Findings were published in the journal ‘Science’. First direct evidence of liquefied water An international team of researchers spotted the liquid water trapped below the ice at the Martian south pole. They detected the liquid after waves from the satellite’s radar passed through Mars’ south pole ice and reflected off the substance below. Water is key to life, and the new findings may be tantalizing because of this fact. “This is the place on Mars where you have something that most resembles a habitat, a place where life could subsist,” planetary scientist Roberto Orosei of the National Institute of Astrophysics in Italy, who led the research, told ‘Reuters’. “This kind of environment is not exactly your ideal vacation, or a place where fish would swim,” he added. “But there are terrestrial organisms that can survive and thrive, in fact, in similar environments. There are microorganisms on Earth that are capable of surviving even in ice.” “This took us long years of data analysis and struggles to find a good method to be sure that what we were observing was unambiguously liquid water,” noted study co-author Enrico Flamini, the former chief scientist of the Italian Space Agency who oversaw the research. The researchers haven’t been able to measure how deep the water is. They believe there’s at least a metre of the substance under the surface, but are unsure if it goes any farther. Because of this, it’s impossible to know whether it forms a lake. It’s entirely possible that there could be very little water there at all. What they do know is that the temperature at the bottom of the ice at the Martian south pole is around - 68 °C. The water remains a liquid because it’s rich in salts. Could life lurk below Mars’ surface? The team says it could be years before it confirms whether something is actually living in this body of water resembling Earth’s subglacial lakes. Could a mission drilling through the ice to sample the water below be far behind? “Getting there and acquiring the final evidence that this is indeed a lake will not be an easy task,” Orosei told ‘The Guardian’. “It will require flying a robot there which is capable of drilling through 1.5 km of ice and this will certainly require some technological developments that at the moment are not available.” According to the study, the researchers will search other sites on Mars for signs of more such lakes. If they exist, that could suggest liquid water has persisted for millions of years, or even dating back billions of years when Mars was a more hospitable planet. The question then becomes whether any life forms that could have evolved long ago on Mars have found a way to survive until now. For now, the supreme question remains: Can Mars support life?