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摘要

Ever since the launch of Sputnik a half century ago, aluminum has been the material of choice for space structures of all types-satellites, sounding rockets, space probes, and launch vehicles. Chosen for its ability to withstand the stresses that occur during launch and operation in space, aluminum has been specified in space applications as divergent as the Apollo flights and Skylab. As complex and dangerous as those missions were, however, the current space endeavor likely eclipses them. For the past 15 years, 100,000 people at 500 contractor facilities in 16 countries have worked with several space agencies on what is likely the most complex construction job in human history: building the International Space Station (ISS). Their objective: to build a mini-city roughly one block long by connecting prefabricated modules launched from Earth 235 miles into low orbit.