A technicians in the Space Station Processing Facility at NASA's Kennedy Space Center in Florida, check the progress of the Payload Attach System, or PAS, as it is lifted up to the Alpha Magnetic Spectrometer, or AMS, where it will be attached to the bottom of the AMS. The PAS provides a method of securely connecting the payload to the International Space Station.
AMS, a state-of-the-art particle physics detector, is designed to operate as an external module on the International Space Station. It will use the unique environment of space to study the universe and its origin by searching for dark matter. AMS will fly to the station aboard space shuttle Endeavour's STS-134 mission targeted to launch Feb. 26, 2011. Photo credit: NASA/Jack Pfaller