The space station, a collaboration between 16 countries, is being assembled piece by piece. More than 50 missions, mostly by the Shuttle, will be needed to transport and assemble all the components. When it is complete the final structure will be longer than a soccer pitch at 108 metres, will weigh 450 tonnes and will have more than 1200 cubic metres of pressurised space. It will support a permanent crew of six astronauts.
