CAPE CANAVERAL — In one of the most harrowing space walks in decades, an astronaut had to rush back into the International Space Station on Tuesday after a water leak in his helmet robbed him of the ability to speak or hear and could have caused him to choke or even drown.
Italian Luca Parmitano, 36, was reported to be fine after the dangerous episode, which might have been caused by an unprecedented leak in his suit's cooling system. His spacewalking partner, American Christopher Cassidy, guided him back inside after NASA quickly aborted the walk.
No one — neither the astronauts in orbit nor flight controllers in Houston — breathed easier until Parmitano was back inside and his helmet was removed.
"He looks miserable. But okay," Cassidy assured everyone.
It was the first such incident since 2004 when Russian and American spacewalkers were ordered back in after 14 minutes by Mission Control outside Moscow because of spacesuit trouble.
In a late afternoon news conference, NASA acknowledged the perilous situation, and space station operations manager Kenneth Todd promised to "turn over every rock" to make sure it never happens again.
The two astronauts were outside barely an hour, performing routine cable work on their second space walk in eight days, when Parmitano reported the leak. It progressively worsened as the minutes ticked by, drenching the back of his head, then his eyes, nose and, finally, mouth. He could have choked or drowned on the floating globs of water, NASA officials said.
Between 1 and 1½ liters of water leaked into his helmet and suit, NASA estimated.
The source of the leak wasn't immediately known, but the main culprit appeared to be iodine-laced water that is piped through the long underwear worn under a spacesuit, for cooling. The system holds nearly a gallon. Less likely was the 32-ounce drink bag that astronauts sip from during lengthy space walks; Parmitano reported the leaking water tasted odd.
The water eventually got into Parmitano's eyes. That's when NASA ordered them back inside. Then the water drenched his nose and mouth, and he had trouble hearing on the radio lines.
Tuesday's spacewalk lasted one hour and 32 minutes.