The idea for the AMS came from Samuel Ting, a Nobel Prize laureate out of MIT. This article documents his "odyssey" to have this built.
Starting in 1994, he threw himself into a project he called the Alpha Magnetic Spectrometer (AMS), a device of nearly eight tons that would be attached to the International Space Station. Essentially a giant magnet for sifting apart the particles in cosmic rays, the AMS will look for evidence of the mysterious dark matter that some physicists believe makes up more than 80 percent of the matter of our universe.
It is quite an informative article, not just about the AMS, but also about Samuel Ting. It also conveyed a very fascinating story on the discovery of the J/psi particle, and how it is another one of those "Who Ordered That?" situation.
Like I said, a very entertaining article. Don't miss it.