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ACCESS (Advanced Cosmic-ray Composition Experiment on the Space Station)

An experiment to study the origin and makeup of cosmic rays over a three-year period. ACCESS will be attached to the International Space Station and was due to replace AMS (Alpha Magnetic Spectrometer) in 2007. Its two instruments, the Hadron Calorimeter and the Transition Radiation Detector, will measure the elemental makeup of cosmic rays from lightest nuclei to heaviest, and determine if the flux of high-energy electrons in cosmic rays varies with direction, as would be the case if some come from local sources.

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