NASA’s latest visitor to Mars has sent its first postcards home – and they offer clear evidence that it is sitting on top of a huge mass of water ice.

The $460 million Phoenix probe’s pin-sharp pictures of the landscape in a far north of the Red Planet show a strange honeycomb pattern of polygons in the permafrost.

NASA say the polygons are a phenomenon observed in our own Arctic. And a British Mars expert told Skymania News that they are a clear sign that water – essential for life – lies beneath the rust-coloured soil.

Dr John Murray, of the Open University, said the honeycomb pattern was evidence of water disappearing into the martian atmosphere in a process akin to evaporation called sublimation.

He said: “They look very much like dehydration cracks where the surface has dried up – like the cracks in a dried-up puddle of mud. They are a clear sign that there has been water at the surface and so there are likely to be vast reserves of it frozen as ice just inches beneath the surface.

“This should be the bottom of an old ocean because the whole northern region of Mars was covered in water two or three billion years ago. All the ancient catastrophic floods on Mars flooded into theis area so it should be like the bottom of the sea.”

Dr Murray, a researcher with the Mars Express mission, believe that the European orbiter has photographed the pattern of Arctic-style pack ice, an indication of the ancient martian seas, in a region called Elysium.

NASA’s mantra has long been to “follow the water”. Phoenix is set to touch it for the first time by actually digging through the soil to collect samples of water ice.

Dr Murray said: “That is the most exciting thing, that we will soon be holding martian ice in our hands – or in the robot’s hands anyway.”

NASA has been at pains to point out that Phoenix is not designed to discover life itself. But scientists are pointing out that it could spot them because it carries two powerful microscopes.

Scientists at Imperial College London engineered the special surface that will hold samples of soil so that they can be examined with a powerful microscope.

Dr Tom Pike, of Imperial, said: “It is very difficult to predict what we might find, but if you wanted to look for signs of the earliest forms of past or present life we will be the first to look closely enough.”

Another UK member of the Phoenix team is David Catling from Bristol University who will investigate weather in the polar region of Mars.

NASA has released another astonishing photo, seen above, that shows Phoenix parachuting towards Mars. Taken from the Mars Reconnaissance Orbiter, it is the first time a probe has been pictured landing on another world.

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