Astronaut Drew Feustel learned a valuable lesson about being teary-eyed on a spacewalk, NASA said Wednesday after the Endeavour crew's third jaunt outside the International Space Station.
"Tears in space don't run down your face," he said, according to lead spacewalk officer Allison Bollinger who described the problem Feustel encountered when out on the spacewalk with astronaut Mike Fincke.
"They actually kind of conglomerate around your eyeball," Bollinger recounted.
The problem occurred toward the end of Wednesday's spacewalk by the two American astronauts who arrived at the orbiting lab along with a six-member crew aboard the shuttle Endeavour 10 days ago.
After stepping out to work on repairs to the Russian side of the station, Feustel discovered some of the anti-fog solution he had buffed on to the interior of his helmet was flaking off.
"We have seen this happen a couple of times in the past where if you are not careful about buffing the anti-fog just the right amount, that it can tend to flake off every once in a while and get in the crew member's eye," said Bollinger. "The anti-fog is just off-the-shelf dishwashing soap. So if you have ever had soap in your eye, you know how that feels."
Feustel, who has completed several spacewalks since becoming an astronaut in 2000, was able to wiggle down far enough in his spacesuit to make use of a spongy device called a Valsalva that is typically used to block the nose in case a pressure readjustment is needed.
"He was able to rub his eye against the Valsalva device to get the tear free," Bollinger said.
The rest of the six-hour, 54-minute spacewalk was routine, NASA said. Scheduled tasks to complete an external wireless antenna system and mend parts of the Russian side of the space station went ahead as planned.
A final spacewalk by two Endeavour astronauts outside the orbiting research station is set for Friday. It will mark the last time U.S. astronauts arriving on board the space shuttle step out for a spacewalk at the lab.
A spacewalk is planned for the Atlantis mission in July, but it will performed by International Space Station crew, not by U.S. astronauts who arrive on the shuttle NASA said.
The Endeavour mission, STS-134, is the second to last for the American shuttle program. After Atlantis's planned launch in July, the three-decade program will end and the shuttles will become museum pieces.
A new pre-spacewalk exercise regimen, known informally as the slow motion hokey pokey and consisting of light exercises and breathing instead of an overnight camp-out in an airlock, was judged a resounding success.
NASA's flight surgeon "reported that there were no medical symptoms whatsoever" with the new approach to preventing decompression sickness, or "the bends" that scuba divers face when encountering changing pressure, said Derek Hassman, lead International Space Station flight director.
"He gave the crew a clean bill of health and the crew had nothing but positive feedback about the protocol -- they really loved the simplicity of the protocol, the fact that it doesn't require as much time on the oxygen masks, it doesn't require the overnight camp-out."
However, the in-suit light exercise (ILE) pre-breathe protocol will not be used for the last spacewalk of the mission on Friday, because it takes up 40 minutes more usage of the canister that scrubs carbon dioxide from the spacesuit.
That could pose a problem for spacewalker Greg Chamitoff, who experienced a malfunction in his C02 sensor during his first spacewalk of the mission.
Since Chamitoff wears an extra-large spacesuit, there are no replacements on board for him to wear.
"It might combine with the possible impacts of the C02 sensor... (and) would reduce the capacity of Greg's suit to the point that we might not be able to do the 6 hour 30 minute EVA," Hassman said, referring to extra-vehicular activity, NASA's term for spacewalk.
However, the new protocol was received so favorably, it will likely become the astronaut's favored method for future spacewalk preparations, he said.