Mars is the closest planet that man-made technology ventured to explore life beyond Earth. The Red Planet has always evoked interest and has provided some of the most profound discoveries by scientists and researchers. The mystery around life and water on the planet continues to spiral. About three years ago scientists confirmed that the dusty, dry red ball that is Mars, has lakes filled with liquid water. The 2018 discovery offered a lot of change in our understanding of Mars. Now, as the quest for ancient microbial life continues, a new study indicates there may be more water on Mars than previously thought.
The research suggests the presence of ‘dozens’ of subsurface ‘’lakes’ in the Martian south pole. Radar signals were found in a region less than a mile beneath the surface of the Red Planet. Known as the South Polar Layered Deposits, it is home to water ice, dust and dry ice that have lived there for millions of years. These radar signals bounced and revealed a shining patch, consistent with an underground pool of liquid water. Subsequent searches revealed more shiny patches, pointing out a whole network of lakes underground. Researchers from NASA’s Jet Propulsion Laboratory examined the data from the European Space Agency’s Mars Express orbiter and observed dozens of radar reflections similar to the discovery made in 2018.
Many of these findings, however, are in regions that are likely too cold for the water to remain liquid. Despite the presence of salty minerals called perchlorates, an actuality currently even baffling the researchers. Study co-author and NASA JPL investigator Jeffrey Plaut, in a statement, said, “’We’re not certain whether these signals are liquid water or not, but they appear to be much more widespread than what the original paper found.” He added that liquid water could be common beneath Mars’ south pole or these radar signals are suggestive of something else. The study carries forward the findings from 2018 when signals from a radar device reflected off Mars’ south pole appeared to show a liquid subsurface lake.
Published in the journal Geophysical Research Letters, the study states that the energy reflected from the base in multiple areas throughout the south polar region is unexpectedly higher than that of the surface. Scientists beamed radio waves from the Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) instrument, to peer through the icy layers, onto the surface. Radio waves lost energy in transmission as they passed through the material in the subsurfaces. They had a weaker signal every time they were reflected back to the spacecraft. In some cases, however, the returning signals were brighter than the ones from the surface, which was elucidated as to “imply the presence of liquid water, which strongly reflects radio waves".
The radar reflections give an understanding of the unexplored area and the subsurface layers that reveal how the tilt in Mars’ axis has shifted in due course of time. The changes could be compared to that seen on Earth when its movement created ice ages and warmer periods throughout the history of the planet.