Two US astronauts Wednesday decontaminated their spacesuits after working more than seven hours to fix a cooling system on the International Space Station, reported the dpa. Doug Wheelock and Tracy Caldwell Dyson entered a secure airlock inside the space station, where they had to wait to make sure no ammonia had clung to their spacesuits. During the seven-hour-26-minute spacewalk, the two astronauts removed a defective pump on the outside of the orbiting ISS that has interfered with the station's cooling system since July 31. A new pump will be installed in the next spacewalk in the coming days. While disconnecting the pump, the astronauts had to disconnect tubes that carry ammonia through the cooling system. NASA officials wanted to make sure that none of the chemical was being carried back into the space station, and sequestered the two in a secure airlock before allowing them back into the station proper.
