CAPE CANAVERAL, Fla. – Astronauts making a rare, hastily planned spacewalk replaced a pump outside the International Space Station on Saturday in hopes of plugging a serious ammonia leak.
The prospects of success grew as the minutes passed and no frozen flecks of ammonia appeared. Mission Control said it appeared as though the leak may have been plugged, although additional monitoring over the next few weeks, if not months, will be needed before declaring a victory.
Christopher Cassidy and Thomas Marshburn installed the new pump after removing the old one suspected of spewing flakes of frozen ammonia coolant two days earlier. They uncovered no smoking guns responsible for the leak and consequently kept a sharp lookout for any icy flecks that might appear from the massive frame that holds the solar panels on the left side.
Let us know if you see anything, Mission Control urged as the fresh pump was cranked up. Thirty minutes later, all was still well. No snow, came the reply.
NASA said the leak, while significant, never jeopardized crew safety. But managers wanted to deal with the trouble now, while its fresh and before Marshburn returns to Earth in a few days.