Luca Parmitano during a spacewalk on 9 July 2013

ESA/NASA

When the water reached my face, it spread over my nose and up into my nostrils in an instant. I was almost blinded, I couldn’t hear anything and I couldn’t breathe through my nose. I already knew I needed to reach the airlock and get back inside the International Space Station. The key question: how long did I have before the water reached my mouth and I couldn’t breathe at all?

When you go on a spacewalk, you enter a new world. It’s an incredibly privileged perspective. Inside the ISS and looking through the windows of the cupola , you’re still inhabiting the safe world of the space station. It’s like staring into a large and really beautiful aquarium. But when I leave the ISS for a spacewalk, I am immersed in the void. I’m in an environment that doesn’t need me. If I wasn’t inside my spacesuit, I would be dead within minutes.

The infinite horizon of stars and blackness is so vivid.…