Water on Mars?
Mars Express is due to deploy its Marsis experiment in May. A huge, frozen sea lies just below the surface of Mars, a team of European scientists has announced. Their assessment is based on pictures of the planet's near-equatorial Elysium region that show plated and rutted features across an area 800 by 900km. The team think a catastrophic event flooded the landscape five million years ago and then froze out. They tell a forthcoming edition of Nature magazine that sediments covered the ice, locking it in place. Large reserves of water-ice are known to be held at the poles on Mars but if this discovery is confirmed by follow-up observations, it would be a first for a region at such a low latitude.