A Soyuz-Fregat rocket is set to blast off at the Baikonur space centre, propelling the 1.2-ton Mars Express probe on its 55-million-km journey to the Red Planet. The main objective is to search for sub-surface water from orbit and drop a lander onthe Martian surface for closer examination.But beyond gatehring vital intelligence, a successful mission will firmly establish Europe and its space agency ESA as a new player in interplanetary exploration.