Nav: Home

Mars might have liquid water

April 13, 2015

Researchers have long known that there is water in the form of ice on Mars. Now, new research from NASA's Mars rover Curiosity shows that it is possible that there is liquid water close to the surface of Mars. The explanation is that the substance perchlorate has been found in the soil, which lowers the freezing point so the water does not freeze into ice, but is liquid and present in very salty salt water - a brine. The results are published in the scientific journal Nature.

In August 2012, the Mars rover Curiosity landed on Mars in the large crater, Gale, located just south of the equator. The giant crater is 154 kilometers in diameter and the rim of the crater is almost 5 kilometers high. In the middle of the crater lies the mountain, Mount Sharp. In over 2½ years, Curiosity has travelled more than 10 km from the landing site towards Mount Sharp and has carried out many studies along the way.

"We have discovered the substance calcium perchlorate in the soil and, under the right conditions, it absorbs water vapour from the atmosphere. Our measurements from the Curiosity rover's weather monitoring station show that these conditions exist at night and just after sunrise in the winter. Based on measurements of humidity and the temperature at a height of 1.6 meters and at the surface of the planet, we can estimate the amount of water that is absorbed. When night falls, some of the water vapour in the atmosphere condenses on the planet surface as frost, but calcium perchlorate is very absorbent and it forms a brine with the water, so the freezing point is lowered and the frost can turn into a liquid. The soil is porous, so what we are seeing is that the water seeps down through the soil. Over time, other salts may also dissolve in the soil and now that they are liquid, they can move and precipitate elsewhere under the surface," explains Morten Bo Madsen, associate professor and head of the Mars Group at the Niels Bohr Institute at the University of Copenhagen.

Riverbed and enormous lake


Observations by the Mars probe's stereo camera have previously shown areas characteristic of old riverbed with rounded pepples that clearly show that a long time ago there was flowing, running water with a depth of up to one meter. Now the new close-up images taken by the rover all the way en route to Mount Sharp show that there are expanses of sedimentary deposits, lying as 'plates' one above the other and leaning a bit toward Mount Sharp.

"These kind of deposits are formed when large amounts of water flow down the slopes of the crater and these streams of water meet the stagnant water in the form of a lake. When the stream meets the surface, the solid material carried by the stream falls down and is deposited in the lake just at the lakeshore. Gradually, a slightly inclined slope is built up just below the surface of the water and traces of such slanting deposits were found during the entire trip to Mount Sharp. Very fine-grained sediments, which slowly fell down through the water, were deposited right at the very bottom of the crater lake. The sediment plates on the bottom are level, so everything indicates that the entire Gale Crater may have been a large lake," explains Morten Bo Madsen.

He explains that about 4.5 billion years ago, Mars had 6½ times as much water as it does now and a thicker atmosphere. But most of this water has disappeared out into space and the reason is that Mars no longer has global magnetic fields, which we have on Earth.

Currents of liquid iron in the Earth's interior generate the magnetic fields and they act as a shield that protects us from cosmic radiation. The magnetic field protects the Earth's atmosphere against degradation from energy rich particles from the Sun. But Mars no longer has a global magnetic field and this means that the atmosphere is not protected from radiation from the Sun, so the solar particles (protons) simply 'shoot' the atmosphere out into space little by little.

Even though liquid water has now been found, it is not likely that life will be found on Mars - it is too dry, too cold and the cosmic radiation is so powerful that it penetrates at least one meter into the surface and kills all life - at least life as we know it on Earth.
-end-
Contact:

Morten Bo Madsen, associate professor and head of the Mars Group at the Niels Bohr Institute, University of Copenhagen, +45 3532-0515, mbmadsen@nbi.ku.dk

University of Copenhagen - Niels Bohr Institute

Related Mars Articles:

How hard did it rain on Mars?
Heavy rain on Mars reshaped the planet's impact craters and carved out river-like channels in its surface billions of years ago, according to a new study published in Icarus.
Does Mars have rings? Not right now, but maybe one day
Purdue researchers developed a model that suggests that debris that was pushed into space from an asteroid or other body slamming into Mars around 4.3 billion years ago and alternates between becoming a planetary ring and clumping up to form a moon.
Digging deeper into Mars
Scientists continue to unravel the mystery of life on Mars by investigating evidence of water in the planet's soil.
A bewildering form of dune on Mars
Researchers have discovered a type of dune on Mars intermediate in size between tiny ripples and wavier dunes, and unlike anything seen on Earth.
Mars is emerging from an ice age
Radar measurements of Mars' polar ice caps reveal that the mostly dry, dusty planet is emerging from an ice age, following multiple rounds of climate change.
Shifting sands on Mars
University of Iowa researchers have a $501,000 NASA grant to travel to Iceland to better understand sand dunes found all over the planet Mars.
Potatoes on Mars
A team of world-class CIP and NASA scientists will grow potatoes under Martian conditions in a bid to save millions of lives.
You too can learn to farm on Mars!
Scientists at Washington State University and the University of Idaho are helping students figure out how to farm on Mars, much like astronaut Mark Watney, played by Matt Damon, attempts in the critically acclaimed movie 'The Martian.'
Similarities between aurorae on Mars and Earth
An international team of researchers has for the first time predicted the occurrence of aurorae visible to the naked eye on a planet other than Earth.
Mars might have liquid water
Researchers have long known that there is water in the form of ice on Mars.

Related Mars Reading:

Best Science Podcasts 2019

We have hand picked the best science podcasts for 2019. Sit back and enjoy new science podcasts updated daily from your favorite science news services and scientists.
Now Playing: TED Radio Hour

Changing The World
What does it take to change the world for the better? This hour, TED speakers explore ideas on activism—what motivates it, why it matters, and how each of us can make a difference. Guests include civil rights activist Ruby Sales, labor leader and civil rights activist Dolores Huerta, author Jeremy Heimans, "craftivist" Sarah Corbett, and designer and futurist Angela Oguntala.
Now Playing: Science for the People

#521 The Curious Life of Krill
Krill may be one of the most abundant forms of life on our planet... but it turns out we don't know that much about them. For a create that underpins a massive ocean ecosystem and lives in our oceans in massive numbers, they're surprisingly difficult to study. We sit down and shine some light on these underappreciated crustaceans with Stephen Nicol, Adjunct Professor at the University of Tasmania, Scientific Advisor to the Association of Responsible Krill Harvesting Companies, and author of the book "The Curious Life of Krill: A Conservation Story from the Bottom of the World".