by Mary Roach
COMMAND MODULE PILOT DAVE SCOTT: Why don’t you let all the rest of the powering down stuff and all that be ours, and you go get your suit off, clean up, try to eat, and go to bed?
SCHWEICKART: Okay. Cleaning up sounds pretty good.
SCOTT: Get one of those towels and wash and…all that stuff. That’ll make you feel better.
SCHWEICKART: Okay. You want to watch the radio?
SCOTT: Yes, I’ll take it.
For reasons we’ll explore momentarily, NASA goes to great lengths to keep its men and women from throwing up in their helmets during a spacewalk. Schweickart and Scott had a serious talk about whether they should skip this particular EVA and just tell NASA they’d done it. Apollo 9 was a critical step in the race to put a man on the moon. The EVA life support system that Neil Armstrong and Buzz Aldrin would wear on the moon had to be tested, as well as rendezvous and docking equipment and procedures. “This is already March of 1969,” recalls Schweickart in his oral history. “The end of the decade is coming right up…. Is this basically a wasted mission because Schweickart’s barfing?…I mean, I had a real possibility in my mind at the time of being the cause of missing Kennedy’s challenge of going to the moon and back by the end of the decade.”
What happens if you vomit in your helmet during a spacewalk? “You die,” said Schweickart. “You can’t get that sticky stuff away from your mouth…. It just floats right there and you have no way of getting it away from your nose or your mouth so that you can breathe, and you are going to die.”
Or not. U.S. space helmets, including those of the Apollo era, have air channels directing flow down over the face at 6 cubic feet per minute, so the vomit would be blown down away from the face and into the body of the suit. Disgusting, yes. Fatal, no. I ran the whole death-by-vomit scenario past Tom Chase, a senior spacesuit engineer at Hamilton Sundstrand. “There would be an extremely remote potential for any barf to get into the oxygen return duct, behind the astronaut’s back,” he began. “It’s one of five returns, including four at the extremities, so even if one was blocked, it would be unlikely to create a complete system blockage. If it somehow did, then the crew member could shut down their fan and go on ‘purge,’ where they would vent out the Display and Controls Module purge valve and continue to get fresh oxygen flowing into their helmet from their pressurized tanks.” Chase shut down his fan for a moment. “So you see we’ve really thought this one through.”
Even if the vomit lingered in front of your nose and mouth, would it kill you? Unlikely. If you inhale your vomit, or for that matter anyone else’s, it will trigger a protective airway reflex: you’ll cough. If all goes as nature intended, the vomit will be turned away at the gates. The reason Jimi Hendrix died from inhaling his vomit (mostly red wine) was that he was so drunk that he’d passed out; his cough reflex was out of commission.
However. Vomit is a more dangerous material to inhale than, say, pond water. As little as a quarter of a mouthful can cause significant damage. The stomach acid that is a routine ingredient in vomit will handily digest the lining of the lungs. Also, vomit, unlike (hopefully) pond water, often includes chunks of recently ingested food: things to get stuck in your windpipe and suffocate you.
If stomach acid can digest a lung, imagine getting it in your eyes. “Barf bouncing off the helmet and back into the eyes would be really debilitating,” says Chase. That’s the more realistic danger with in-helmet regurgitation. That and vision-obstructing visor splatter.
Visor glop is a serious astronautical downer. In the words of Apollo 16 Lunar Module pilot Charlie Duke, “I tell you, it’s pretty hard to see things when you’ve got a helmet full of orange juice.” (Actually, Tang.)* Duke’s in-suit drink bag began leaking† during suit checks on board the Lunar Module. (In-suit drink bags are NASA’s version of the Camelbak bag.) Mission Control surmised the problem was zero-gravity-related and that it would “settle out” under lunar gravity. It did not, or not entirely. Here is Charlie Duke in the Apollo 16 mission transcript, driving on the moon, the high point of his life, as a pair of oddly named craters come into view: “I can see Wreck and Trap and orange juice.”
Historically, the people who needed to worry about inhaling their vomit were not astronauts, but early surgery patients. Anesthesia, like a gallon of red wine, can both make you throw up and deaden your cough reflex. This is one reason the modern surgery patient is made to fast before the operation. In the rare event of a full stomach making its way into the operating room and disgorging its contents, doctors are equipped with an aspirator. In Hendrix’s case, rescue personnel employed “an 18-inch sucker.”
And you do want the model with the large-diameter suction tubing. In 1996, four physicians from the Madigan Army Medical Center in Fort Lewis, Washington, compared the time it took to aspirate an average mouthful (90 milliliters) of simulated inhaled vomit, using first standard suction tubing and then a new, improved large-diameter model. The latter, as reported in the American Journal of Emergency Medicine, was ten times as fast, and less likely to suck up portions of lung.
Perhaps you are wondering what the doctors used as their “vomitus-simulating substance.” They used Progresso vegetable soup. The Progresso Web site media-mention list includes Food & Wine, Cook’s Illustrated, and Consumer Reports, but not, understandably, the American Journal of Emergency Medicine. Judging from their Web site, the Progresso people would be horrified if they knew. They have a fairly highbrow view of canned foods, even going so far as to recommend wine pairings for their product line.
Has the in-helmet upchuck ever actually come to pass? I was told that it happened to Schweickart, but my source later recanted his testimony. Charles Oman told me he knows of only one in-suit incident, and “the volume was small.” It happened in the airlock of the International Space Station, while the astronaut was preparing for a spacewalk. Oman did not divulge the regurgitator’s name; being sick in your spacesuit retains a stigma to this day.
Though not nearly as powerful as it was in Schweickart’s day. The attitude during Apollo, Schweickart recalls, was that “motion sickness is something that weenies suffer.” Cernan agrees: “To admit being sick was to admit a weakness, not only to the public and the other astros, but also to the doctors….” Who might then decide to ground you. In his memoir, Cernan describes feeling sick during Gemini IX, but not letting on lest his colleagues think of him as “some nugget on a summer cruise.”
Apollo 8 commander Frank Borman covered up his motion sickness. I’ll let Schweickart cast the first stone: “It was well known in the astronaut corps that Frank had barfed more than once, but…for all kinds of reasons which are Frank’s, he wouldn’t really come forward with it.” That left Schweickart to wear the hat that says, as he puts it, “the only American astronaut who had ever barfed in space.” (Motion sickness during the Mercury and Gemini space programs was less common, probably because the capsules were extremely cramped; there wasn’t enough motion for sickness.) Borman much later admitted that he was, as Cernan wrote in his memoir, “sick as a dog* all the way to the moon.”
Following his flight, Schweickart dedicated himself to the study of space motion sickness. “I went over to Pensacola, and…I became the guinea pig, the pincushion that people stuffed their pins in and their probes in and whatnot. For six months,…my main job was learning as much as we could about motion sickness. And frankly, we didn’t learn that much, and we don’t know that much about it today, to be honest with you.” The work was worthwhile in that, if nothing else, Schweickart managed to drag motion sickness out of the closet. “Rusty paid the price for us all,” Cernan wrote. “Nothing was ever said in public against him, but he never flew another mission.”
Things were said in public about Jake Garn, the astronaut-senator from Utah. Things were said in a nationally syndicated comic strip. Doonesbury cartoonist Garry Trudeau had been lam-basting Garn’s 1985 shuttle flight as a costly boondoggle. When Trudeau got wind of the fact that Garn was ill for much of the mission,
one of his characters referred to “the Garn” as the unit by which space motion sickness would henceforth be measured. (In reality, there is no unit, but there is a scale, starting at “Mild Malaise” and ending at “Frank Vomiting.”)
Pat Cowings laughed louder than most. When Garn was in training, Cowings had offered to teach him a biofeedback technique she developed for preventing space motion sickness. He waved her away, saying, “Yeah, I heard about that California meditation stuff. Will it grow back my hair?” (Despite what seem to me to be impressive results, Cowings to this day struggles with biofeedback’s touchy-feely reputation. Even her own employer doesn’t use her method. “I say to NASA: There’s this big company? They’re called the Navy? And they’re using it now.”)
No one, not Jake Garn or Rusty Schweickart or Frank Vomiting, should be embarrassed about getting sick in space. Some 50 to 75 percent of astronauts have suffered symptoms of space motion sickness. “That’s why you don’t see much shuttle news footage the first day or two. They’re all, like, throwing up in a corner somewhere,” says Mike Zolensky, NASA’s curator of cosmic dust. Zolensky himself was epically sick on a parabolic flight. The only passenger worse off was the one helping astronauts practice drawing blood in zero gravity. Since his arms were strapped down, someone else had to hold the bag to his face.
Technically speaking, motion sickness is not a sickness. It’s a normal response to an abnormal situation. It hits some people faster and harder than it hits others, but everyone can be made to hurl. Even fish can get seasick. One Canadian researcher recalls a story told to him by the owner of a codfish hatchery. The fishmonger had call to transport some of his tank-raised charges by sea. “After the boat had been under way for some time, all the feed they had eaten was seen to be on the bottom of the tank.” The researcher listed all the species known to be susceptible to motion sickness: monkeys, chimps, seals, sheep, cats. Horses and cows can be nauseated but cannot, for anatomical reasons, throw up. There is disagreement, he said, about birds.* The author put forth that he personally had witnessed a pigeon vomiting while being spun on a rotating platform. “It is unusual,” he added. I’d say.
The only humans who are predictably immune are those with nonfunctioning inner ears. It was a group of five “deaf-mutes” who failed to fall ill on a harrowing sea voyage that first alerted science to the link between motion sickness and the vestibular system. The year was 1896. Among the miserable was a physician named Minor. He states in his paper that he had heard of two other parties of deaf-mutes—twenty-two in the first group and thirty-one in the second—who regularly made long sea voyages without falling ill. Prior to Minor’s paper, medical science had blamed motion sickness on lurching stomach contents and oscillating air pressure in the gut. A variety of girdles and belts were prescribed in Lancet articles around the time. Readers responded with their own stomach-stabilizing strategies: Singing, holding one’s breath as the boat crests the swells, and “eating pickled onions freely.” The rationale behind the last one being that it produces gas, which inflates the stomach and steadies abdominal pressure. The singing and flatulence perhaps explains the preponderance of deaf-mutes on ocean voyages around that time.
Ironically, NASA Ames motion sickness researcher Bill Toscano has a defective vestibular system. He didn’t realize it until he rode the rotating chair. “We thought there was something wrong with the chair,” says Toscano’s fellow researcher Pat Cowings. I carried on a conversation with Toscano while he sat in the rotating chair, his voice rising and fading with each revolution. It’s his superpower.
Since motion sickness is a natural response to a novel or sensorially perplexing motion or gravitational environment, astronauts have to go through it all over again when they return to Earth after a long mission. During the weeks or months of no gravity, their brains have been interpreting all otolith cues as acceleration in one direction or another. So when they move their head, their brain tells them they’re moving. Astronaut Peggy Whitson described her first moments on Earth after coming back from 191 days on the International Space Station like this: “I stood up and the world was going around me at 17,500 miles per hour, as opposed to me going around the world at 17,500 miles per hour.” It’s called landing vertigo, or Earth sickness. (Other obscure motion sickness spin-offs include amusement park ride sickness, spectacle sickness, wide-screen movie sickness, camel sickness, flight simulator sickness, and swing sickness.)
Vile as it is, the act of vomiting deserves your respect. It’s an orchestral event of the gut, complex and seamlessly coordinated: “There is a forced inspiration, the diaphragm descends, the abdominal muscles contract, the duodenum contracts, the cardia and oesophagus relax, the glottis closes, the larynx is drawn forward, the soft palate rises, and the mouth opens.” Small wonder an entire “emetic brain”—or “vomiting center”—is devoted to the cause. Somewhere, I recall reading that the dinosaur formerly known as brontosaurus had a brain at the base of its tail to coordinate its lower body movements. I envisioned a brain-shaped gray organ nestled in the dinosaur’s pelvis. Now I think I was wrong. Because the “emetic brain” isn’t an actual brain any more than the Vomiting Center has a parking lot and a board of trustees. It’s just a place in the fourth ventricle, a few clusters of nuclei a fraction of a millimeter across.
In the case of motion sickness, vomiting is an impressive lot of bother for no apparent reason. Vomiting makes sense as a bodily response to poisoned or contaminated food—gets it out of you ASAP—but as a reaction to sensory conflict? Pointless, says Oman. He says it’s just an unfortunate evolutionary accident that the emetic brain happened to evolve right next to the part of the brain that oversees balance. Motion sickness is most likely a case of cross talk between the two. “Just one of God’s jokes,” says Pat Cowings.
IN THE 1980 London stage version of The Elephant Man, Joseph Merrick commits suicide* by lying down on his bed and allowing his grotesquely enlarged head to hang over the edge and crush his airway. It was suicide by gravity. His head had grown so heavy that his neck muscles could no longer lift it. For 20 seconds at a time, I’ve been feeling what that’s like. When the C-9 pulls out of its downward dive to begin another climb, we are accelerated into the floor with the force of approximately 2 G’s, twice the Earth’s gravity. My head suddenly weighs 20 pounds, not 10. Like Merrick, I’m lying on my back—not to kill myself, but because I’ve been told this lowers the odds of becoming nauseated. It’s very strange. I can’t pick my head up off the floor of the plane.
I read somewhere that a beached whale will die from an overdose of gravity. Out of the water that normally buoys them, their lungs and body weigh so much that they collapse in on themselves. The whale’s diaphragm and rib muscles aren’t strong enough to expand its lungs and raise the now far heavier blubber and bone that press in on them, and the animal suffocates.
Aerospace researchers in the 1940s figured out a way to mimic excess gravity here on Earth. A rat or rabbit or chimp or, eventually, a Mercury astronaut, would be placed at the end of a long, spinning centrifuge arm. Centrifugal force accelerates body parts and fluids outwardly, away from the center of the centrifuge. As we learned and most likely forgot in chapter 4, gravity is simply your rate of acceleration. So, to mimic standing erect in excess gravity, a researcher would have subjects lie with their feet at the outside end of the spinning arm. The faster the centrifuge spins, the heavier grow the subject’s organs, bones, and body fluids.
You can see what a rat’s organs look like inside its body at 10 G’s and 19 G’s by tracking down the February 1953 issue of Aviation Medicine and opening to p. 54, but I don’t recommend this. A team of Navy commanders at the Aviation Medical Acceleration Laboratory figured out an ingenious and horrific “quick-freeze technique,” whereby anesthetized rats were immersed in liquid nitrogen while riding a centrifuge. The now nineteen times heavier blood in the heart has pooled at the bottom of the organ and weighed it down, elongating it like a wad of stretched Silly Putty. The ab
dominal organs are packed down into the pelvis like sandbags, the head has sunk down into the shoulders, and I don’t even want to talk about the testicles. A second photograph shows the rat facing the other way around—its head at the outer end of the centrifuge arm. The extraheavy organs are now in a pileup under the rib cage, crushing the lungs and leaving the rest of the torso bizarrely empty.
The commanders were not simply entertaining themselves. The early aeromedical scientists studied the human tolerance limits for excess gravity in order to learn how to protect fighter pilots and, later, astronauts. Jet pilots are subject to as many as 8 or 10 G’s as they pull out of steep dives and execute other high-speed maneuvers. Astronauts endure a few seconds of double or triple gravity during liftoff, and as many as four and sometimes more extra G’s when their spacecraft reenters Earth’s atmosphere on the way down. Going from the airless vacuum of space into a wall of air molecules slows their craft from 17,500 to a few hundred miles per hour. As in any abruptly slowed vehicle, the occupants are hurled forward in the direction of travel. What’s dangerous about reentry is that the hurling—the period of doubled or quadrupled G forces—lasts for up to a minute, as opposed to the split-second duration of a car crash.
How many excess G’s the human body can tolerate without injury depends upon how long it’s exposed. For a tenth of a second, people can typically hack between 15 and 45 G’s, depending on what position they’re in relative to the force. When you get up into the range of a minute or more, tolerance drops alarmingly. Your heavy blood has enough time to pool in your legs and feet, depriving your brain of oxygen, and you black out. If it goes on long enough, you die. At 16 G’s, wrote John Glenn of his flight-training experience on the NASA centrifuge, “it took just about every bit of strength and technique you could muster to retain consciousness.” This is why astronauts lie down during reentry—so the blood doesn’t pool in their legs and feet. But on your back, you are the whale on the beach. There is pain beneath the breast-bone. Inhaling is a struggle. During a Soyuz reentry that went awry, ISS Expedition 16 commander Peggy Whitson endured an overly steep, overly fast reentry and a full minute in 8 G’s, about double the normal hypergravity of reentry. Astronauts are taught, on the centrifuge, how to deal with this—to take quick, shallow panting breaths so the lungs never fully deflate and to inhale using the stronger muscles of the diaphragm, not the smaller muscles attached to the ribs. Even then, Whitson found it a struggle.