When man is launched into space, a consideration as earthly as the weather often has the last say on whether the crucial liftoff goes ahead as scheduled. China's second manned space mission is no exception. This morning, weather permitting, the Shenzhou VI orbital module and its two astronauts will be launched by a Long March rocket on their five-day mission. On the eve of what is expected to be another technological and scientific milestone for China, the expected arrival of a strong cold air mass over the Jiuquan space centre in Gansu province was not the only focus of attention. The nation was kept waiting until the last moment for confirmation of which pair of the six astronauts shortlisted for the mission were to have the honour of being the country's second and third men in space. As with the launch of the Shenzhou V space mission two years ago - China's first manned space flight - preparations for the launch were shrouded in secrecy. The fact that all six astronauts, in three mission-ready pairs, were taken to the space centre for the launch is evidence of meticulous preparations aimed at leaving nothing to chance. It is a reminder, more than four decades after the former Soviet Union and the United States launched the manned-flight club, that space exploration remains a highly risky enterprise. Despite the formal secrecy, it appeared that Nie Haisheng and Fei Junlong had been selected from the shortlist to man Shenzhou VI. Doctors attached to the nation's space programme would have to have been satisfied that both astronauts selected were fit for the arduous mission. One of the back-up pairs was ready to take over, if for example, the selected crew caught a cold at the last minute. China's first manned space flight by former PLA fighter pilot Yang Liwei was greeted abroad with wide acclaim and at home with a wave of national pride in a prestigious achievement that dramatised the country's growing role on the world stage. It ranked with accession to the World Trade Organisation and Beijing winning the right to host the 2008 Olympic Games. That wave of pride washed over Hong Kong and left it with an abiding interest in the nation's role in space exploration. Few would have forgotten the overwhelming reception our city extended to Colonel Yang during a six-day visit to Hong Kong soon after his pioneering mission. The architects of China's space programme have laid out ambitious plans ranging from moon walks to the building of a space station. If all goes according to plan, today's flight will confirm China as a leading space power ready to play a greater role in international co-operation - the key to modern space exploration. The world will wish Shenzhou VI a successful mission and a safe return home.