Astronauts on the International Space Station may take a spacewalk Saturday to repair an ammonia leak.
The gas, used to cool one of the station's solar arrays, began oozing from the left side of the station's truss structure Thursday, officials said.
"The whole team is ticking like clockwork, readying for tomorrow. I am so proud to be Commander of this crew. Such great, capable, fun people," Hadfield tweeted Friday morning.
Astronauts Chris Cassidy and Tom Marshburn are checking their spacesuits for a potential walk to examine the leak site, NASA said. Both have three spacewalks under their belts, collaborating on two of them during a 2009 mission, the agency said.
Evidence of the leak emerged when the crew reported seeing small white flakes floating away from an area on the station's Port 6 truss structure, NASA said. Hand-held and remotely operated cameras helped locate the leak, which appeared to be worsening, according to the space agency.