Nightly News | July 16, 2013
>>> few americans paused to think about the international space station up there with a crew on board orbiting earth every 90 minutes , until something goes wrong, which it did earlier today. during a space walk , while cameras recorded it all, as an astronaut's helmet started to fill with water. our report on it tonight from nbc's tom costello.
>> reporter: chris cass identity and italian astronaut luca luca parmatano were only an hour into their space walk when luka reported an incident.
>> i feel a lot of water on the back of my head.
>> are you sweating, are you working hard?
>> i am sweating, but it feels like a lot of water.
>> reporter: fellow astronaut cass identity took a look. sure enough, water was beading down his forehead. at first they thought his drinking water bag was leaking. it seemed to be too much water for that to be the source.
>> it's too much.
>> i don't know, it's a lot.
>> as he struggled to see and here, mission control called off the space walk .
>> water's in his eyes now, and it seems to be increasing. we think we're going to terminate ev 2.
>> reporter: within minutes, he was back in the space station with russian and american crew members working fast to remove his helmet. water floated out and they needed towels to dry him off. nearly a liter and a half leaked into his suit. did it come from the cooling system?
>> clearly we have a problem at this point that we don't quite understand.
>> reporter: former astronaut and veteran space walker steve robinson .
>> we're going to have to understand, if it happened to this space suit , is there any danger of it happening to another space suit on board.
>> reporter: he was in danger, now an urgent investigation to determine what happened. tom costello, nbc news, washington.