“You’re stone cold.”

The test conductor (TC) seemed to delight in telling me that I just committed a fatal spacewalking error (there are many to choose from). Her clever comments weren’t needed to teach me the importance of proper tethering. The life-saving handrail retreating from my outstretched glove was obvious enough. In space, my transgression could have sent me into an irreversible trajectory away from the International Space Station (ISS), rendering me just another piece of space junk adrift in low-Earth orbit.



This, however, was an exercise at NASA’s pool used for spacewalk training, the Neutral Buoyancy Laboratory (NBL) in Houston. I'd hear similar admonitions at least twice more during the day, as SCUBA divers hovered close by to keep my free-floating tendencies (and my future as a meteor) in check.

My day at the pool was one of the highly coveted opportunities for non-astronaut “test subjects” to don a spacesuit (NASA calls it the EMU—Extravehicular Mobility Unit) and experience first-hand some of the peculiarities of working in space. While this insight is valuable to the engineers who deal with the EMU and space tools, that wasn't the point of this event. My function was to periodically play the role of a distressed and unconscious astronaut for the benefit of the divers who are tasked with rescuing such unfortunate souls during “real” training events.

I suppose that being given the opportunity to put on an EMU could lead one to feel a twinge of self importance. The suit, however, has a way of metering such delusions of grandeur with heaping doses of humility. In fact, the first step of the sizing process involves standing before a full-mirrored wall in government-issue skivvies while a team of caliper-toting technicians measures your every dimension. Then comes the moment when you actually have to get into the EMU, the upper part of which is completely rigid. Imagine forcing your way into an extremely overstarched shirt… while it remains buttoned and hanging in the closet. Success requires equal parts contortionism and masochism.

For many, their first minute in the EMU is a defining moment. You’re either going to be good with it, or you’re going to be clawing rabidly to get out right now! It’s not that the suit isn’t comfortable once you’re fully buttoned up, it’s just rather confining. If you get antsy during an MRI, just go ahead and shred your astronaut application form now. There’s no room for your claustrophobia in the EMU.

In the often cryptic acronym-based NASA lingo, astronauts do not perform spacewalks. Instead, they “go EVA” (extravehicular activity). As astronauts invariably go EVA with a partner, so goes the NBL. My plus-one in this venture was Robert Knight, a fellow engineer with four previous gigs in the pool. We agreed to an ambitious set of tasks that would test our presumed EVA skills, with some obligatory faux fainting spells that would challenge our acting chops. Perhaps even ersatz astronauts are competitive by nature.

Test subjects and astronauts alike are bound to an unwritten yet rarely broken NBL commandment: “thou shalt feed the staff.” Donuts and kolaches are staples of the morning menu. When astronaut Nicole Stott is at the pool, you have to act fast to nab one of her homemade cookies. Robert and I splurged on a heavy stash of breakfast burritos that we hoped would satiate the divers and spare us some of the good-natured hazing that is due all test subjects (and most astronauts).

Following breakfast and a smattering of preliminary tasks, a crane lowered us into the water. Here the enormous full-scale mockup of the ISS came in to clear view. Sure, 6.2 million gallons sounds like a big pool, but it’s impossible to comprehend its true vastness until you pierce the surface and take in all three dimensions (202’ × 102’ × 40’). I had to limit my gawking due to the extreme fisheye effect that the EMU helmet creates in water. This distortion doesn’t manifest itself in space or air, but it can be very disorienting and nauseating in the pool. I focused intently on the tools stowed just below my helmet until my eyes could adjust.

My three support divers took me down 40 feet to the pool floor. They placed foam and/or weights in various pockets of the EMU to make it neutrally buoyant in order to emulate the weightlessness of space. In open water, Robert and I were completely dependent on the divers for mobility (this is where the breakfast investment pays off). They spun and twirled us into countless orientations while fine-tuning our buoyancy.

By this time, my eyes were well adjusted and I was enjoying myself immensely. It was like a slow-motion roller coaster ride with a magnificent view. I especially liked being placed on my back. I was able to see a panoramic perspective of the ISS mockup slightly above and all around me. I watched the diver’s bubbles race toward the ceiling lights that were randomly skewed by the choppy surface of the pool. This Dali-esque scene felt very surreal and I never tired of it. Unfortunately, Robert was not faring quite as well. On this day, his eyes refused to adjust to the helmet-altered visual perspective. He wisely conceded defeat to the onrushing nausea and was removed from the pool.