Second spacewalk due Wednesday after first effort stalls NASA engineers are once again scrambling to find a way to restore the International Space Station's ailing cooling system to full strength after weekend spacewalk repair efforts were stalled.
Leaking ammonia coolant and a stuck hose forced American astronauts Douglas Wheelock and Tracy Caldwell Dyson to cut short their attempts to replace a faulty cooling system pump during a Saturday spacewalk. The astronauts plan to stage another spacewalk to tackle the problem on Wednesday, and then - if all goes well - finish replacing the pump during an extra spacewalk on Sunday. "We are pressing ahead with the second spacewalk on Wednesday," NASA spokesperson Rob Navias told Space.com. Wheelock and Caldwell Dyson spent more than eight hours working outside the space station Saturday to try to disconnect the oven-sized ammonia pump from its mooring on the space station's right side. But one of four liquid ammonia hoses initially refused to budge, and then began leaking ammonia once Wheelock freed it by hammering on the connector with a tool. The ammonia pump failed July 31 and knocked out half of the space station's main cooling system. The space station crew has turned off some systems and left others running without backups to prevent the orbiting lab from overheating. [ Graphic: Inside and Out: The International Space Station] The faulty pump is in one of two cooling loops serving the space station's U.S. segment. A second loop is working fine, mission managers have said. The space station's Russian segment also has its own independent cooling system, they added. NASA engineers and mission managers spent all of last week planning Saturday's attempted spacewalk repair. The job was already so complicated that two spacewalks would be necessary, station managers said at the time. http://www.msnbc.msn.com/id/38630196/ns/technology_and_science-space/ _______________________________________________ Medianews mailing list [email protected] http://lists.etskywarn.net/mailman/listinfo/medianews
