It is one of the most iconic scenes of exploration - the white-suited astronaut floating freely through space. It's beautiful, astonishing, and extremely dangerous. No one has ever died while on a spacewalk (or even in space, for that matter), but astronauts assume risk every time they leave their protective capsules.
NASA calls spacewalks EVAs - extra vehicular activities. They have been a part of the space program since the Gemini days and today are a vital capability for maintaining the International Space Station. Since the launch of the ISS, the EVA has become a routine part of living in space.
It's this routine nature which masks the dangers and difficulties of working in space. Early astronauts struggled to simply move around; it took improvements in the suits, the handholds placed on spacecraft, and the astronauts' training before any real work could be done. Even today, trouble can still strike. Back in July, spacewalking astronaut Luca Parmitano was working outside the ISS when his helmet began to fill up with water. He made it safely back inside the station, but not before water began floating around his face. A subsequent examination showed that his suit cooling system had leaked into his breathing apparatus.
Last week that same spacesuit was needed again - this time to repair a malfunctioning cooling system that had shut down much of the ISS. Astronauts had repaired the suit, but in a move which reveals the rough-and-tumble nature of space exploration, NASA engineers also suggested the crew build a snorkel out of drinking straws. No water was detected during this week's EVAs, but other problems with the cooling system cut one walk short and delayed another.
If you saw the film Gravity earlier this year, I've probably had no difficulty in convincing you that space is scary, dangerous, and difficult to work in. If you haven't, I highly recommend you check it out. Many astronauts have remarked that it best captures the experience of walking in space.
And, in a time when astronauts are sometimes seen less as heroes and more as construction workers, we should strive to keep in mind that space is the most dangerous construction site in the world. They put their lives on the line to give us the amazing discoveries we marvel at every day.