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<b>Mars Express to Deploy 'Divining Rod' </b><br /><br />LINK<br /><br />A "divining rod" to search for underground water on Mars will be deployed on Europe's Mars Express spacecraft early this spring, after a year of delays. The new deployment date for the radar antenna - to be announced within days - is likely to fall in April 2005.<br /><br />Mars Advanced Radar for Subsurface and Ionosphere Sounding - or MARSIS - consists of wires strung inside three long fibreglass tubes. These will seek water - which might provide oases for life - as deep as several kilometres below the Martian surface.<br /><br />The tubes, currently folded and stored onboard Mars Express, were originally scheduled for deployment in April 2004. But mission managers postponed the date when computer simulations showed that a similar antenna planned for launch later in 2005 could swing back and damage the spacecraft upon deployment. So the MARSIS team spent several months last autumn running vacuum-chamber tests of the antenna material and modelling the deployment on computers.<br /><br />The research now reveals that there is indeed a "high likelihood" that one of the three tubes "will whip back and strike the spacecraft", says MARSIS manager William Johnson of NASA's Jet Propulsion Laboratory in Pasadena, California, US. "But the antenna is quite light and flexible - about the diameter and strength of a toilet paper tube," he adds. "So the impact would most likely not cause any damage." <br /><br />Centre of gravity<br /><br />More worrisome than a direct hit is the small chance that a tube could get caught on the spacecraft or tangled up with itself. In that case, MARSIS would not work and could leave the spacecraft with a new and unanticipated centre of gravity, forcing mission managers to tweak how they control the probe. "There is some risk attached to this," Johnson told New Scientist.<br /><br />But officials at the European Sp