Mars soil gives Nasa scientists some major surprises
In addition to expected materials, the planet's sands hold chemicals known as perchlorates
Analysis of Martian soil by Nasa's Mars Curiosity rover has exposed a surprising amount of water, as well as a chemical that would make a search for life more complicated, according to scientists.
A scoop of fine-grained sand collected by the rover in August last year showed the soil contained about 2 per cent of water by weight.
If you take a cubic foot of that soil you can basically get two pints of water out it. The soil on the surface is really a little like a sponge for sucking stuff out of the atmosphere
"It was kind of a surprise to us," said Curiosity scientist Laurie Leshin of Rensselaer Polytechnic Institute. "If you take a cubic foot of that soil you can basically get two pints of water out it," she said. "The soil on the surface is really a little like a sponge for sucking stuff out of the atmosphere."
Scientists announced last week that so far the planet's atmosphere showed no signs of methane, a gas which on earth is strongly tied to life. Plumes of methane had been detected over the past decade by Mars orbiters and ground-based telescopes.
Methane, which should last about 200 years under Martian photochemistry, can also be produced by geologic events.
The water was found by heating a tiny bit of soil to 835 degrees Celsius inside Curiosity's chemistry laboratory and analysing the resulting gas releases.
Scientists found that in addition to water, sulphur dioxide, carbon dioxide and other materials, the sands of Mars also contain reactive chemicals known as perchlorates.