Mary Roach - Packing for Mars

Given the culpability of the human otolith, it is not surprising to learn that sudden head movements are extremely, to use the lingo of motion sickness experts, “provocative.” If you look at back issues of Aerospace Medicine, you can find pictures of grim-looking World War II troops with their heads wedged between padded vertical slats on the walls of troop transport planes: someone’s attempt to stem the vomitous tide. (The smell of other people’s emissions in close quarters is also highly “provocative.” Cowings likes the term “inspirational.”) Airsickness and seasickness were serious enough problems during the war that the government, in 1944, convened an entire United States Subcommittee on Motion Sickness. (Then again, it has also convened a U.S. Subcommittee on Poultry Nutrition and one on sedimentation.) Charles Oman, resident motion sickness expert at the National Space Biomedical Research Institute, confirmed the perils of wanton head-swiveling by mounting accelerometers on the backs of astronauts’ headwear. The ones who, just by nature, tend to jerk their heads around a lot are the ones most likely to suffer from motion sickness during a mission. What’s true in space is true in a car on a winding road: No matter how much the driver behind looks like the GEICO caveman, don’t whip your head around to look. According to work done by prolific 1960s motion sickness researcher Ashton Graybiel, even one head movement in highly susceptible people produces a measurable increase in their sweat level—an indication that nausea is just around the bend. [23] Intestinal activity has also been looked into as a warning bell for incipient nausea. One Space Shuttle astronaut wore a “bowel sound monitor” on his belly for the duration of the mission. Don’t feel bad for him; feel bad for the Air Force security guy assigned to listen to two weeks of bowel sounds to be sure no conversations including classified information had been inadvertently recorded.

“We actually proposed making a beeping beanie,” Oman said. If astronauts moved their head too fast or too much, they’d hear a beep letting them know. Oman did not record the astronauts’ responses to the beeping beanie proposal, but I’m guessing they were fairly, as they say, “provocative,” for no astronautical beanie-wearing ensued. Oman did manage to get astronauts on one mission to agree to try out padded collars designed to discourage extraneous head movements, which they promptly removed. “It was perceived as an irritant,” Oman said ruefully.

Astronauts have to deal with the mother of all sensory conflicts: the visual reorientation illusion. This is where up, without warning, becomes down. “You were working on a task…and apparently reorienting your ‘down’ without thinking about it, and then turning away and finding that the whole room was completely cattywampus to what you thought it was,” recalls a Spacelab astronaut quoted in one of Oman’s papers. (This may have been Pat Zerkel’s problem; he told me he’d had “the distinct feeling of losing any sense of up or down.”) It happens most readily in spaces with no obvious visual clues as to which is the floor and which the ceiling or wall. The Spacelab tunnel was notorious. One astronaut found traveling through it so reliably nauseating that, he told Oman, he’d sometimes pay a visit simply to make himself “get better by vomiting.” Even just a glimpse of a fellow astronaut oriented differently from oneself could bring it on. “Several Spacelab crew described sudden vomiting episodes after seeing a nearby crew member floating upside down.” [24] Hanging around upside down is inconsiderate to your crewmates for another reason. It’s hard to understand what someone is saying when his mouth is upside down. We rely on lip-reading more than we think in everyday conversation. Astronaut Lee Morin told me that it’s very hard to read someone’s lips if he or she is tilted more than 45 degrees. Plus, he added, “you get the chin thing.” Chins look like noses. Very distracting. Nothing personal.

Experts like Oman keep changing their minds about whether drugs are a good idea. In space, as at sea, recovery is a process of adaptation; if you’re under the covers in the fetal position, you’re not exposing your vestibular system to the new reality. Overdoing it, on the other hand, can mean crossing the threshold and making yourself sick. Drugs help keep astronauts out of bed, moving and going about their work. But they also confer a false sense of immunity, encouraging one to overdo it. Motion sickness drugs don’t make you immune; they simply raise the threshold for sickness.

For anyone taking a short trip, across the Channel or on the C-9, drugs are the answer. NASA gave us Scop-Dex (the dextroamphetamine counteracting the sedating effects of the scopolamine). Even then, most flights have at least one or two “kills,” as the blue flight suits call the stricken. Pat looked queasy before the parabolas even began. It’s possible he’s someone who developed a conditioned response to the sight of a vehicle—in his case, a plane—that once upon a time made him horrifically ill. People who say they “get sick just looking at a boat” are not always exaggerating. (Relaxation and counterconditioning techniques can help in these cases.) People also develop conditioned responses to the smell of vomit. “This is why motion sickness can seem contagious,” says Oman.

One thing the Pensacola research proved is that it helps to focus on something other than how you are feeling. The eight who finished rotisserating on the human disorientation device were those who had been given “constant mental arithmetic” tasks or timed button-pushing sequences to complete. Mental as opposed to written, because the last thing you want to be doing when you’re fighting off motion sickness is reading. In particular, avoid reading papers such as “Analysis of Vomitus and Contents of Gastrointestinal Tract.”

RUSTY SCHWEICKART DID everything wrong. Schweickart was an astronaut on Apollo 9, charged with testing the life-support backpack that the Apollo 11 crew would wear on their history-making stroll on the moon. Schweickart was to put it on, power it up, and head into the depressurized Lunar Module. Because he’d been sick during parabolic-training flights, he’d been exceedingly cautious the three days leading up to the spacewalk. “My whole modus operandi…” he said in his NASA oral history, “was to keep my head as still as possible and not to move around a lot.” There’s the first problem: He delayed his adaptation. On day three, Schweickart had to put on his EVA suit. This is, as he describes it, a “real contortionist challenge” with a lot of ducking down and doubling over. Problem 2: head movements. “Suddenly I had to barf,…and I mean, that’s not a good feeling. But of course you feel better after you barf.” Encouraged, he continued his preparations, moving over to the Lunar Module. Problem 3: the dreaded visual reorientation illusion. “You’re used to being up, and when you go over there, it’s down.” When he got there, he had to wait for his crewmate to catch up to where he was on the checklist of tasks. “I’ve basically got nothing to do.” Problem 4. “When your mind is suddenly—[its] priorities are gone, then…malaise gets the top priority in your brain. All of a sudden, I had to barf again.”

With space motion sickness, the impulse to vomit can hit with unusual suddenness. One of Oman’s Spacelab interviewees recalls sitting with a colleague who was eating an apple. “Right in the middle of it, he said, ‘Aw gee!’ threw the apple in the air, and vomited just like that.” Launch-pad workers stuff extra vomit bags in rookies’ pockets before liftoff, but even then, unfettered hurls are common. [25] On a parabolic flight, evasive maneuvers are critical. Joe McMann, who used to run NASA’s EVA Management Office, told me he was once flying with a man who threw up very abruptly. “I realized that in about three seconds, that vomit is going to come down on me in 2 G’s. I was doing all kind of motions to get out of the way.” One NASA employee I met swears double gravity makes it harder to throw up. NASA etiquette is to clean it up yourself. As one of Oman’s Spacelab interviewees says, “Nobody else is going to do that work for you—and you sure don’t want anybody to.” Though you couldn’t accuse Schweickart’s fellow astronauts of a lack of compassion. Herewith, the most touching moment in the 1,200-page mission transcript from Apollo 9.