After several minutes of deliberation, NASA’s Mission Control ordered Parmitano to return to the airlock and directed Cassidy to end his activities as well by gathering tools and equipment.
At that point, it appeared water might be leaking from Parmitano’s internal space suit drink bag. That assessment changed as the two astronauts conferred in the airlock and began to remove their protective space suits
“Clearly the water did not taste like the normal drink water,” relayed Cassidy to Mission Control. The water tasted of iodine, a chemical placed in the water that circulates through tubing as a coolant in the undergarments worn by spacewalkers. The iodine inhibits microbial growth.
Cassidy also reported possible damage in the “belly button” portion of Parmitano’s space suit and moisture around a cooling vent in the back of his colleague’s helmet.
The leak was unparalled in ISS spacewalk operations, said Karina Eversley, who served as the lead spacewalk officer in NASA’s Mission Control. “Choking or drowning were definitely possiblities,” Eversley told a news July 16 news briefing.
Evidence gathered in the aftermath, including photos and comments from Cassidy and Parmatano, indicated the 32-oz. drink bag in his suit was not the leak source, said Eversley and David Korth, the NASA flight director during the excursion. Parmitano wore the same space suit during his July 9 spacewalk.
Though their outing was greatly abbreviated, Cassidy managed to complete external power cable reconfigurations he began July 9. The changes provide a second source of electricity to an assortment of critical systems, including control moment gyros, thermal control and Ku-band communications links, in response to external electrical or cooling system failures.
The alteration will enable astronauts to reroute power to critical systems from inside the station rather than interrupt other activities to prepare for a spacewalk.
Meanwhile, Parmitano extended U.S. power and data utility cables to a power and data grapple fixture installed on the Russian segment. The grapple fixture serves as one of several anchor points for the station’s Canadian robot arm. The 58-ft. robot arm often serves as a mobile work platform for spacewalking astronauts.