Liquid water is one of the most important ingredients for life.
Scientists have long suspected that there is liquid water near the polar caps on Mars but there has been no evidence to prove it — until now.
A paper recently published in international journal Science has found radar evidence that a lake of salty, liquid water may be sitting under a layer of ice at Mars’ south pole. The stable reservoir is estimated to be 12 miles (20 kilometers) across and at least one meter thick.
The discovery was made using a radar instrument called MARSIS (Mars Advanced Radar for Subsurface and Ionosphere Sounding) on the European Mars Express spacecraft. The Italian Space Agency (ASI) led the development of the MARSIS radar and NASA provided half of the instrument.
Read more: NASA finds ancient organic matter on Mars
The research paper outlines how a “bright spot” was detected in radar signals about one mile (about 1.5 km) below the surface of the ice cap in the Planum Australe region of Mars. The authors of the study interpreted this strong radar reflection as liquid water.
In a news statement, NASA’s chief scientist Jim Green said, “The bright spot seen in the MARSIS data is an unusual feature and extremely intriguing. It definitely warrants further study. Additional lines of evidence should be pursued to test the interpretation.”
“We hope to use other instruments to study it further in the future,” he added.
According to the statement, NASA’s InSight lander is one of the instruments that will be used later this year to carry out further investigations on Mars. It will include a heat probe that will burrow down as far as 16 feet (five meters) below the surface of the planet. The probe, built by the German Aerospace Center (DLR), will help provide crucial data on how much heat escapes the planet and where liquid water could exist near its surface.
Although Mars is inhospitable today, there is clear evidence that billions of years ago the climate of the planet was warmer and there was liquid water pooled on its surface. Data from NASA’s Curiosity rover has also revealed that in the distant past, a water lake inside Gale Crater on Mars held all the ingredients necessary for life, including energy sources and chemical building blocks. Scientists say that these findings are a good way to uncover what happened to the ancient Martian seas that were once abundant on the planet.