NASA Mystified by Source Of Water in Astronaut Luca's Spacesuit

European Space Agency (ESA) astronaut Luca Parmitano’s spacesuit filled up with 1-1.5 liters of water during an hour-and-a-half spacewalk outside the International Space Station (ISS) this morning.   NASA terminated the spacewalk early and still does not know where the water came from.

Parmitano, often referred to simply as Luca, was in the early stages of a planned 6.5 hour spacewalk with NASA astronaut Chris Cassidy when he noticed an unusual amount of water collecting at the back of his head.    The spacesuit has a drink bag with 32 ounces (just less than 1 liter) of water to drink during the lengthy excursion outside.  After ruling out perspiration, the drink bag was the next most likely culprit, but as time went on the amount of water increased, covering his ears and reaching his eyes.  NASA ground controllers terminated the spacewalk and ordered both astronauts back inside, Luca first.  By the time he was being helped out of his suit by the other four ISS crew members, the amount of water had increased to an estimated 1-1.5 liters (33-51 ounces) and was impeding his ability to see, hear or communicate.

At a NASA press conference this afternoon, lead spacewalk officer Karina Eversley confirmed that  “choking or drowning was definitely a possibility” in the fishbowl environment of the spacesuit’s helmet.  In microgravity, water collects in “globs,” she explained, and he would not have been able to simply cough out any water that entered his mouth as one can do on Earth.

NASA flight director David Korth said the ISS crew and engineers on the ground are troubleshooting the incident but “nothing is jumping out” as the cause.  The “easy answer” was the drink bag and “we’ve almost ruled that out,” he said.  Another potential source of the water is the suit’s cooling and ventilation system, which has about 1 gallon (3.8 liters) of water, Eversely said.   Korth added that a carbon dioxide sensor in Luca’s suit had failed several minutes before Luca noticed the water buildup and moisture has caused CO2 sensor failures in some prior spacewalks.   Another possibility is an anti-fogging agent that keeps the visor clear of condensation.

Korth and Eversley said there are at least two functional spacesuits still aboard the ISS.  If an emergency necessitated another spacewalk before the root cause of this anomaly is determined and resolved, the ISS crew could still do one, but for now NASA is in no rush to complete the tasks scheduled for today.  They and Kenny Todd, chairman of the Mission Management Team for this mission, painted a positive picture of the contingency that focused on how well Luca, his fellow crew members, and the ground team reacted to the emergency.   Todd stressed that the number one objective is to get the crew back into the ISS safely, and that was achieved.  The crew was reported to be in good spirits.

The spacewalk lasted just 1 hour and 32 minutes, the second shortest spacewalk from the ISS.  In addition to Parmitano (who is Italian) and Cassidy, the other four ISS crew members are NASA astronaut Karen Nyberg and Russian cosmonauts Alexander Misurkin, Pavel Vinogradov, and Fyodor Yurchikhin.