China: no date yet for moon landing

China hasn\'t finalized a timetable for its manned moon landing program, a senior scientist working on the country\'s lunar orbiter project said. \"Putting a man on the moon involves a very complicated systematic program with many technical challenges to solve, including those related to conducting space walks, docking, staying on the moon and returning,\" Ouyang Ziyuan, chief scientist for the lunar orbiter project, said Wednesday at a scientific conference in north China\'s city of Tianjin. China\'s lunar plans include unmanned moon exploration, a manned moon landing and the building of a moon base but no timetable is in place, he said. \"China won\'t carry out a manned moon landing until it masters all of [the] crucial technologies,\" he said. China has launched two lunar orbiters, Chang\'e-1 in 2007 and Chang\'e-2 in 2010, to gather scientific data and make high-resolution maps of the moon, China\'s official Xinhua news agency reported. China plans to send a third probe, the Chang\'e-3, to the moon in 2013 and retrieve it in 2017 with samples of the moon\'s surface, Ouyang said.