Astronauts fix ISS cooling system in long spacewalk

Two astronauts fixed a faulty cooling systemTuesday on the orbiting International Space Station in aseven-and-a-half-hour spacewalk, US space agency NASA said according to dpa. Americans Rick Mastracchio and Michael Hopkins spent an hour longerthan planned floating outside the station in only the second-everChristmas Eve spacewalk in the history of NASA, the US space agency. They could be seen working busily throughout the endeavour in livevideo on NASA's website. Tuesday's work followed a five-and-a-half-hour spacewalk on Saturday,when ISS crew members began the cooling system repairs by detaching amalfunctioning pump module. The astronauts had been due to replace the module during a spacewalkon Monday, which was postponed after a fault was detected inMastracchio's spacesuit following Saturday's walk. He was fitted touse a reserve suit, which he wore Tuesday.