Marte com lago de gelo. Crédito: Pixabay

Scientists find liquid water in Mars for the first time

Unprecedented discovery increases chances of finding life on Mars and rises the hopes of settling human missions and colonies on the red planet

The European Space Agency (ESA) and the Italian Space Agency announced the discovery of liquid water on Mars. A water lake of about 20 km in diameter was found hidden under the planet’s 1.5-km south polar ice cap. According to researchers, the water body has features similar to those of the Arctic and Antarctic sub-glacial lakes.

Published on an article by Science Magazine, the discovery was only possible thanks to a new technology called Mars Advanced Radar for Subsurface and Ionosphere Sounding (Marsis). The instrument takes some sort of X-Ray image of Mars' surface: its radar is capable of scanning even the planet’s thickest ice caps. The first evidence that the region where the water was found would be a promising one is that its anomalously bright subsurface reflections were reflecting stronger than usual. A more detailed examination revealed the huge water lake.

Using data collected between May 2012 and December 2015 by Mars Express - a mission launched to space in 2003 -, scientists completed their calculations and proved that this sparkling anomaly is in fact liquid water, even at temperatures below the freezing point - it is estimated that the water temperature is below 10 °C (14° F).

On an interview to BBC World News, Roberto Orosei, researcher for the University of Bologna and author of the discovery, explained: “This phenomenon is the result of heavily salinized waters containing high concentrations of magnesium, calcium, and sodium, elements markedly present on Mars rocks”.

Lago em Marte. Crédito: ESA/NASA/Viking

It is still impossible to say how deep the Martian lake is, but scientists believe the total volume of water may be of billions of liters. The existence of water on Mars had been already proved, but only in frozen form. A few grooves suggesting the existence of channels on the surface were the only evidence of liquid water. This new discovery might break grounds when it comes to finding life outside of Earth and accomplishing the quest for setting human feet on Mars.

Possible life on Mars can make it easier for humans

Sending space missions to Mars or even settling human colonies on the planet runs against one of its main obstacles: the lack of water. The huge newly-found subglacial lake might be of great help when it comes to putting Mars projects together. However, one should still figure out how to pull this water from the ground. Besides, the whole combination of salts the water is made of contains elements that can be used in the production of fuel for a potential base to be built there.

The existence of liquid water allows scientists to speculate that we are closer than ever to meet possible life forms in Mars – life, as we know it, is intrinsically linked to water. Even on a hostile environment like the red planet, whose atmosphere is very thin, consisting mainly of carbon dioxide (95% of total), and whose atmospheric pressure is too low (1% of the Earth’s sea level), researchers now see this undertaking as reasonably possible.

“Of course, these are not the most pleasant conditions for any form of life,” said Orosei to BBC. “What we know for sure is that under similar conditions (as in Antarctic lakes), some multicellular organisms manage to survive,” he added.

On Earth, the environment whose conditions are closest to those of the Martian lake is Lake Vostok, in Antarctic, the world’s largest subglacial lake. Bacteria featuring primitive life forms were found there, and later full micro-organism ecosystems.

One month ago, NASA scientists announced on Science Magazine another discovery showing evidences that life really existed on Mars. They found organic material well preserved among three billion-year rocks nestled within craters across the red planet. Data was collected by the Curiosity robot, launched from the Earth to Mars in 2012.

“Ancient organic materials and mysterious methane gas! Curiosity found a new evidence preserved on the rocks suggesting that the planet might have supported life in the past, plus a new evidence on the atmosphere linked to men’s current quest for life in Mars", wrote the robot to NASA on his Twitter account.