They are testing the waters again.
Two NASA astronauts floating outside the International Space Station embark on a series of spacewalks - as part of a marathon project to repair the outpost's cooling system.
It's the first spacewalk since July, when Italian astronaut Luca Parmitano's helmet started filling with droplets of water. It could have caused him to drown.
Flight engineers Rick Mastracchio and Mike Hopkins are conducting the spacewalk.
Hopkins is a first-time spacewalker. He's wearing the same spacesuit the Italian astronaut was wearing when his helmet began filling with water.
Both NASA astronauts have rigged their helmets with homemade snorkels, in case of another water leak. NASA's confident that won't happen.
This spacewalk was prompted by a shutdown of one of the station's two ammonia cooling systems on Dec. 11.
That forced the crew to turn off non-essential equipment stopping dozens of science experiments.
Although the six
