Amazing Pictures Of International Space Station

When renovations or repairs are needed on the International Space Station, it's up to astronauts to do the job. Before donning a special pressurized suit and heading out on a spacewalk, though, they must first spend over two hours decompressing in order to avoid the bends. Once their spacesuits are on, the astronauts must spend another hour breathing pure oxygen before they can step outside. Photograph courtesy NASA science.nationalgeographic.com — See photos of the International Space Station and download free desktop wallpapers from National Geographic. Click Here for the Amazing Pictures Of International Space Station