Underwater Spacewalks

Steve Squyres conducts an underwater
By Aquanaut Steve Squyres (Cornell University)

Image at right: Steve Squyres conducts an underwater spacewalk.

Extra-vehicular activity. Spacewalk. Whether you say it in NASA-ese or plain English, a walk in space conjures up images of floating serenely above the Earth’s surface (or maybe above an asteroid), enjoying the freedom that only zero-gravity can afford.

The reality, however, can be a little different.

Nobody does a spacewalk just for fun. Yep, they’re fun, no doubt about it… ask anybody who’s done one. But they’re always done with a purpose. If you couple that sense of purpose with a solid emphasis on safety, the reality of a spacewalk is that it becomes an intricate matter of managing tools, equipment and tethers. Lots and lots and lots of tethers.

I’m the one non-astronaut on the NEEMO 16 crew, so I don’t have the months of training in EVA tricks and procedures that my fellow crewmembers have. Luckily, though, I come from a mountaineering background, where we use the same kind of equipment — nylon slings and carabiners — that the astronauts use on orbit. It’s really the same kind of problem… you need to move around, and you need to clip yourself reliably to something so that you don’t drift (space) or fall (mountains) off into nowhere.

So the good news is that I sorta know what I’m doing. The bad news is that we all have to do a lot of it! We don’t go anywhere without two safety tethers holding us down to something. Any piece of equipment we have with us has to have a tether. The box that holds all the tethers has a tether. And on and on and on. You can see from the picture how it looks. Do it right, and everything works reasonably well. Do it wrong, and you’ve got spaghetti.

We did it pretty well today, most of the time. But you’ve really got to keep your focus. Drifting serenely above the Earth, or an asteroid, or the sea floor definitely has a certain appeal. But if you want to do it right, you also have to be pretty good at not getting tangled.

To learn more about the NEEMO 16 mission, visit: www.nasa.gov/neemo.