Astronaut Luca Parmitano frantically tried to come up with a plan to save himself as water filled his helmet during a spacewalk outside the International Space Station (ISS) last month.
Parmitano has written about the experience on his blog.
The incident happened on 16 July, when Parmitano and his fellow astronaut Chris Cassidy, were about an hour into their six-hour and 15-minute spacewalk. Parmitano began to feel water behind his head and when it got into his eyes, ISS flight director David Korth ordered the two men back inside the orbiting space lab.
Parmitano wrote about how it was easier said than done.
“I realised that to get over one of the antennae on my route I will have to move my body into a vertical position, also in order for my safety cable to rewind normally,” Parmitano wrote.
“At that moment, as I turn ‘upside-down’, two things happen: the Sun sets, and my ability to see – already compromised by the water – completely vanishes, making my eyes useless; but worse than that, the water covers my nose – a really awful sensation that I make worse by my vain attempts to move the water by shaking my head. By now, the upper part of the helmet is full of water and I can’t even be sure that the next time I breathe I will fill my lungs with air and not liquid.”
To make matters worse, Parmitano wrote, he realised he couldn’t even understand which direction he should head in to get back to the airlock.
“I can’t see more than a few centimetres in front of me, not even enough to make out the handles we use to move around the Station.
“I’m alone. I frantically think of a plan. It’s vital that I get inside as quickly as possible. I know that if I stay where I am, Chris will come and get me, but how much time do I have?”
Parmitano used his safety cable to help him return the airlock, all the while thinking about what he would do if the water reached his mouth.
“The only idea I can think of is to open the safety valve by my left ear: if I create controlled depressurisation, I should manage to let out some of the water, at least until it freezes through sublimation, which would stop the flow. But making a ‘hole’ in my spacesuit really would be a last resort.”
Parmitano made it safely back inside the ISS with the help of his crewmates, and now US space agency NASA is investigating the incident.
The spacewalk – the second one to have taken place last month – was to finish the installation of bypass jumpers to provide power redundancy to critical station components, route cables for a new Russian Multipurpose Laboratory Module set to arrive later this year, and complete maintenance and inspection tasks, NASA had said.
“Space is a harsh, inhospitable frontier and we are explorers, not colonisers. The skills of our engineers and the technology surrounding us make things appear simple when they are not, and perhaps we forget this sometimes,” Parmitano wrote.
“Better not to forget.”