<i>From ESAPortal</i><br /><br /><font color="red"><font size="5"><center><b>Mars Express radar ready to work</b></center></font></font><br /><hr /><br /><br /> <br />22 June 2005<br />ESA PR 34-2005. MARSIS, the Mars Advanced Radar for Subsurface and Ionosphere Sounding on board ESA’s Mars Express orbiter, is now fully deployed, has undergone its first check-out and is ready to start operations around the Red Planet.<br /> <br />With this radar, the Mars Express orbiter at last has its full complement of instruments available to probe the planet’s atmosphere, surface and subsurface structure.<br />MARSIS consists of three antennas: two ‘dipole’ booms 20 metres long, and one 7-metre ‘monopole’ boom oriented perpendicular to the first two. Its importance is that it is the first-ever means of looking at what may lie below the surface of Mars. <br /><br />The delicate three-stage phase of radar boom deployment, and all the following tests to verify spacecraft integrity, took place between 2 May and 19 June. Deployment of the first boom was completed on 10 May. That boom, initially stuck in unlocked mode, was later released by exploiting solar heating of its hinges. <br /><br />Taking advantage of the lessons learnt from that first boom-deployment, the second 20-metre boom was successfully deployed on 14 June. Subsequently, ESA’s ground team at the European Space Operations Centre (ESOC) in Darmstadt, Germany, commanded the non-critical deployment of the third boom on 17 June, which proceeded smoothly as planned. <br /><br />MARSIS’s ability to transmit radio waves in space was tried out for the first time on 19 June, when the instrument was switched on and performed a successful transmission test. <br /><br />The instrument works by sending a coded stream of radio waves towards Mars at night, and analysing their distinctive echoes. From this, scientists can then make deductions about the surface and subsurface structure. The key search is for water. But MARSIS's capabilities do not <div class="Discussion_UserSignature"> <font color="#800080">"All God does is watch us and kill us when we get boring. We must never, ever be boring" - <strong>Chuck Palahniuk</strong>.</font> </div>