The Water-Lakes-on-Mars Debate Just Got More Interesting - Gizmodo

In 2018, a team of Italian scientists claimed to have discovered a subglacial lake near the Martian south pole using radar data from the Mars Express satellite.

The radar signals from the 2018 study pointed to a 12-mile-wide (20-kilometer) region around a mile beneath the surface, which the researchers interpreted as a subglacial lake or a patch of liquid water.

The study suggests that there is indeed an accumulation of liquid water beneath the planet’s south polar ice cap.

“The combination of the new topographic evidence, our computer model results, and the radar data make it much more likely that at least one area of subglacial liquid water exists on Mars today,” Neil Arnold, a researcher at Cambridge’s Scott Polar Research Institute and lead author of the study, said in a statement.

But a separate new paper suggests that the liquid water radar data was in fact a result of interaction between different geological layers on Mars, producing a reflection pattern that could have been misinterpreted as liquid water.

“On Earth, reflections that bright are often an indication of liquid water, even buried lakes like Lake Vostok [under the surface of the East Antarctic Ice Sheet],” Dan Lalich, research associate with Cornell Center for Astrophysics and Planetary Science and lead author of the study, said in a statement.