Traces of Martian life: the search continues

Radar sounders aboard ESA's Mars Express and NASA's Mars Reconnaissance orbiters have already detected ice deposits deep underground. Now, after a ten-month journey, NASA's Phoenix lander will continue the search for water. Its objective is to land in a permafrost region near the north pole. Its suite of instruments will scan the atmosphere and a robotic arm will attempt to dig down to an ice-rich layer expected to lie at arm's reach below the surface. But water is not the sole element that could have harboured life on the Red Planet: methane could also establish a link between life on Earth and Mars. Scientists have already found traces of methane in the atmosphere of Mars and are currently trying to work out exactly where the gas is coming from. On Earth, it is well known that the source of methane is mostly life. So, whilst orbiting spacecraft like Mars Express continue to harvest global views, in-situ observations on the martian surface like those of NASA's Phoenix lander and ESA's ExoMars mobile laboratory, due to launch in 2011, remain necessary. The critical entry, descent and landing phase of the Phoenix probe will, at NASA's request, be provided with support from ESA.ESApod video programme