Published: Thu, July 26, 2018
Sci-tech | By Jackie Newman

Scientists find first persistent water source on Mars

Scientists find first persistent water source on Mars

A lake of liquid water has been detected by radar beneath the southern polar ice cap of Mars, according to a new study by Italian researchers from the Italian Space Agency, published Wednesday in the journal Science.

Finding more liquid water on Mars may mean moving beyond radar technology, which is limited to detecting large quantities of water close to the surface.

But the climate has changed significantly over the course of the planet's 4.6 billion year history and liquid water can not exist on the surface today, so scientists are looking underground.

In 2015, in the first-ever definitive signs of the presence of liquid water on the Red Planet, Nasa's Mars Reconnaissance Orbiter (MRO) captured strong evidence for seasonal flows of liquid salty water on the Martian surface.

Now, the ISA believes it's found a 20km wide underground lake of liquid water locked under thick ice near the planet's south pole. The discovery, which was made possible by a ground-penetrating radar on the European Space Agency's Mars Express spacecraft, is "thrilling and exciting", he said.

Whether microbial forms of life could lie within is a matter of debate. Together with the pressure of the overlying ice, this would lower the melting point, allowing the lake to remain liquid as happens on Earth.

Those pulses reflected 29 sets of radar samples that created a map of drastic change in signal nearly a mile below the surface.

Even if this new discovery is validated, experts are lukewarm about whether this body of water would be suitable for life.

Mars's southern polar ice cap
Mars’s southern polar ice cap

Mars Express scientists Roberto Orosei and his team found a 12.5 mile patch of Mars with high permittivity-so high that the numbers like that are nearly always associated with liquid water, including lakes lurking under glaciers in Greenland and Antarctica. The blue triangle indicates an area of very high reflectivity, interpreted as being caused by the presence of a reservoir of water, about a mile below the surface. The search for liquid on the planet on the part of MARSIS has been ongoing for the last 12 years.

The lake resembles one of the interconnected pools that sit under several kilometers of ice in Greenland and Antarctica, says Martin Siegert, a geophysicist at Imperial College London, who heads a consortium trying to drill into Lake Ellsworth under West Antarctica.

The tool is called the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS), and was created to find subsurface water by sending radar pulses that penetrate the surface and ice caps.

Marsis wasn't able to determine how deep the layer of water might be, but the research team estimate that it is a minimum of one metre.

Early results from Mars Express already found that water-ice exists at the planet's poles and is also buried in layers interspersed with dust.

Given its location beneath the polar ice cap, the water is expected to be below the freezing point of water.

"It will open up a very interesting area of science on Mars", he said. The bright horizontal feature at the top represents the icy surface of Mars in this region. Learning more about these caps can reveal Mars' climate history.

Syria blasts evacuation of White Helmets as 'criminal'
Panicked passengers, fearing for their lives, posted pictures of the militia surrounding their buses on social media. The National News Agency said 850 Syrians living around the border town of Arsal were repatriated on Monday.

Like this: