Space: Five NASA spacewalks aborted due to bad suits
We’ve looked at some of the woes of space exploration before and its thanks to New Scientist for this one, returning to the topic of Space. Specifically, looking at design issues with space suits. Of course, when you are so far from earth the slightest problem can be very significant…
Victoria Jaggard writes:
While drowning is an uncommon risk for astronauts, for Luca Parmitano, the threat seemed very real. The Italian astronaut and his fellow spacewalker Christopher Cassidy brought their work outside the International Space Station (ISS) to an abrupt end on 16 July 2013 after water started leaking into Parmitano’s helmet. The pair went back inside the station and removed their spacesuits, with Parmitano needing several towels to mop water from his face as his helmet came off. It is not yet known what caused the sudden soaking.
This is not the first time that astronauts have had to deal with wardrobe malfunctions in space. Here’s more on Parmitano’s unexpected dousing and some of the spacesuit errors NASA has had to address:
1. Wet head
A damp head would not usually be a life threatening issue on Earth. But in the microgravity of space, water floats in blobs that tend to stick to surfaces. In Parmitano’s case, enough water seeped out at the back of his helmet that it began flowing around his face and pooling in his ears. “I can still hear perfectly, but my head is really wet and I am feeling that it’s increasing,” he told mission control. A few minutes later: “Now it’s in my eyes.”
Once the suit was removed, crews reported that between 1 and 1.5 litres of leaked water had accumulated inside it, according to lead spacewalk officer Karina Eversley of NASA’s Johnson Space Center in Houston, Texas. “Choking or drowning is definitely a real possibility,” she said of the incident during a press briefing today.
2. Helmet rain
Parmitano is not the first to have this problem. In February 2004 Russian cosmonaut Alexander Kaleri ended a spacewalk early because he also experienced watery build-up in his helmet. “It’s strangely warm,” Kaleri told Russian flight controllers at the time. “It’s amazing. I have rain inside the helmet. I have water on the visor.” Crews on the ground saw signs of a problem with his suit’s cooling system and sent Kaleri and US astronaut Mike Foale back inside the ISS.
Underneath a spacesuit’s pressurised outer layer, astronauts wear a spandex garment lined with narrow tubes that circulate chilled water to help keep the bottled-up spacewalkers cool. Foale found a kink in one of these tubes in Kaleri’s suit. He straightened out the tube, and water once again flowed normally.
3. Under pressure
The shortest spacewalk yet happened in June 2004, when a mission had to be aborted after just 14 minutes. US astronaut Mike Fincke was headed outside the ISS to repair a circuit breaker, but the main oxygen tank on his Russian Orlan spacesuit began rapidly losing pressure almost as soon as he left the airlock. Flight controllers sent the astronaut back inside to troubleshoot. They found that an injector switch inside the suit, designed to let astronauts control the flow of oxygen, was not fully in the “off” position before Fincke headed out. The suit was once again cleared for flight, and the spacewalk was rescheduled for a few days later.
4. Ruin the gauntlet
In space, a cut on your glove is a reason to get indoors in a hurry. A 2007 spacewalk ended early when US astronaut Rick Mastracchio noticed a cut in the thumb of his pressurised glove. The cut only affected the top two layers of the five-layer protective material, so Mastracchio was not in immediate danger. But NASA rules required him to stop the spacewalk as a precautionary measure. The astronaut noticed the hole during a regular visual inspection of the gloves, which NASA made mandatory after crews on the ground discovered a similar cut on a suit worn during a spacewalk in December 2006.
Future suits might use smart materials such as self-healing polymer gels to repair these kinds of cuts on the fly.
5. Bad air
US astronaut Cassidy is no stranger to spacesuit dilemmas – he had his own spacewalking glitch in 2009. Cassidy was outside the ISS installing new batteries for the space station’s solar array when the carbon dioxide level in his air supply suddenly shot up. The level stayed within accepted limits, but NASA ended the outing early to be on the safe side. The lead spacewalk officer at the time, Keith Johnson, said the problem was probably with the suit’s CO2 scrubber, so crews put a replacement instrument in the suit and Cassidy was able to resume working outdoors the next day.
“Spacewalks are a key part of the human spaceflight programme and can do some spectacular things. But of course all spaceflight does have risk,” Eversley said [following the Parmitano problom]. NASA will spend the next day or two talking to Parmitano and the rest of the crew and evaluating the leaky suit, to see if the problem can be found and fixed. In the meantime, Parmitano is enjoying his drier surroundings aboard the ISS. “Luca’s doing great,” Eversley said. “He’s smiling and happy.”
(Note: New Scientist article first published 17 July 2013)
(Image: NASA – NASA is testing ideas for spacesuits that could be worn on the moon. )Tags: astronaut, christopher cassidy, eversley, space, space exploration