Packing for Mars: The Curious Science of Life in the Void

by Mary Roach

The Outer Space Treaty, of which the United States is a signer, prohibits claims of sovereignty upon celestial bodies.

the materials are for a test of patience and accuracy under pressure. The

Mission specialist astronauts carry out the science experiments, make the repairs, launch the satellites. They’re still the best and the brightest, but not by necessity the boldest.

NASA’s recommended astronaut attribute list includes an Ability to Relate to Others with Sensitivity, Regard, and Empathy. Adaptability, Flexibility, Fairness. Sense of Humor. An Ability to Form Stable and Quality Interpersonal Relationships.

two things compound the usual stresses: the deprivations of the environment and one’s inability to escape it.

Make sure they speak a common language well enough to communicate. Check out how well they work as a team. Choose people with a resilient sense of humor. Give everyone a crash course in cross-cultural etiquette.

Sometime around the sixth week of a mission,

astronauts begin to withdraw from their crewmates, become territorial, and displace their hostility for each other onto Mission Control.

cross-cultural misunderstanding and “natural man-woman situations.”

Fritz and Heinz Haber, who, in 1950, dreamed up a technique known today as parabolic flight.

He has a minor in explosives and the slightly bitter, misanthropic personality of someone who shouldn’t.

Anything that generates heat tends to overheat, because there are no convection currents in the air.

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.

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.

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.

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.

Safeguarding a human for a multiaxis crash is not all that different from packing a vase for shipping. Since you don’t know which side the UPS guy’s going to drop it on, you need to stabilize it all around. Race-car drivers are strapped tightly into custom-fitted seats with a lap belt, two shoulder belts and a crotch strap to keep them from sliding down under the lap belt. A HANS (Head and Neck Support) device keeps the head from snapping forward, and vertical bolsters along the sides of the seat keep the head and spine from whipping left or right.

Snellen eye chart

necropsy (the animal version of an autopsy),

Outer space is list world: cuff checklists, lunar surface checklists, lists of mission rules and “get-ahead tasks.”

Field Test Plan includes time lines, objectives, a four-page hazard analysis, an Off-Nominal Situation Resolution Tree and, for each simulated traverse, science priorities, targets of opportunity, get-ahead tasks, and mission rules.

I’ve been an astronaut for six years, and I’ve been in space for eight days.”

Axilla (armpits) and groin occupy the top two slots because that’s where the body’s apocrine sweat glands are. Unlike the body-cooling eccrine sweat glands, which secrete mainly water, the apocrine glands produce a cloudy, viscous secretion that, when broken down by bacteria, creates the hallmark BO punch.

The apocrine glands are hooked up to the autonomic nervous system; fear, anger, and nervousness prompt an upswing in secretions.

Eventually the mind stops registering the body’s smell. In Leyden’s words, “It’s going, ‘I don’t need to bother telling you this anymore.’” Unfortunately for a group of AMRL subjects in a twenty-day no-bathing Apollo simulation, this point didn’t arrive until day eight.

Some people* are genetically unable to smell (i.e., they’re anosmic to) one or both of the two BO heavies: 3-methyl-2-hexanoic acid and androstenone.

healthy skin sheds 10 million particles a day, and 10 percent of those harbor bacteria. Dry, damaged skin flakes off more readily than healthy, lubricated skin and thus disperses more bacteria. Damaged skin also harbors more pathogens than healthy skin.

Dandruff is caused by an inflammatory skin response to oleic acid, which the scalp fungus Malassezia globosa excretes after dining on your scalp oils. Either you’re sensitive to oleic acid or you’re not.

Every time you go for a run or lift a heavy box, you cause minute amounts of damage to your bone. The osteocytes sense this and send in a repair team: osteoclasts to remove the damaged cells, and osteoblasts to patch the holes with fresh ones. The repaving strengthens the bone. This is why bone-jarring exercise like jogging is recommended to beef up the balsa-wood bones of thin, small-boned women of northern European ancestry, whose genetics, postmenopause, will land them on the short list for hip replacement.

extremely osteoporotic women have been known to break a hip (actually, the top of the thighbone where it enters the pelvis) by doing nothing but shifting their weight while standing. They don’t fall and break a bone; they break a bone and fall.

the greater trochanter, where people fall and hit their hips.”

the hydrostatic indifference point.

The jump—slated for summer or fall 2010 in an undisclosed locale—will provide escape-system engineers with hard-to-come-by information about the behavior of a falling body in a pressurized suit in extremely thin air and the reactions of that body to transonic and supersonic speeds. Because there’s so little air resistance up there, Baumgartner is expected to reach 690 miles per hour, rather than the 120-miles-per-hour terminal velocity of a typical free fall at lower altitude. No one has ever bailed out in a spaceflight emergency, and it isn’t clear how best to do it safely in all phases of flight.

Suddenly the man in the spacesuit is not an underpaid civil servant; he’s the ultimate extreme athlete. Red Bull knows how to make space hip.

an obscure shock-wave phenomenon called shock-shock interaction comes into play. When a reentering spacecraft breaks apart, hundreds of pieces—none with the carefully planned aerodynamics of the intact craft—are flying at hypersonic speeds, creating a chaotic web of shock waves. Clark likened them to the bow waves behind a water-skier’s boat. At the nodes of these shock waves—the places where they intersect—the forces add together with savage, otherworldly intensity. “It

You are not really sitting on the seat. You are hovering in close proximity. The tendency, says Broyan, is to touch down too far back. Then your angle of approach is off, and you sully the back of the transport tube and plug some of the air holes that encircle the rim. Bad, bad move. Space toilets operate like shop vacs; “contributions,” to use Broyan’s word, are guided along, or “entrained,” by flowing air rather than by water and gravity, two things in short-to-nonexistent supply in an orbiting spacecraft. Plugged air holes can disable the toilet.

Everything these men and women learned as toddlers—how to cross a room, how to use a spoon, how to sit on a toilet—must be relearned for space.

The simple act of urination can, without gravity, become a medical emergency requiring catheterization and embarrassing radio consults with flight surgeons. “The urge to go is different in space,” says Weinstein. There is no early warning system as there is on Earth. Gravity causes liquid waste to accumulate on the floor of the bladder. As the bladder fills, stretch receptors are stimulated, alerting the bladder’s owner to the growing volume and delivering an incrementally more insistent signal to go. In zero gravity, the urine doesn’t collect at the bottom of the bladder. Surface tension causes it to adhere to the walls all around the organ. Only when the bladder is almost completely full do the sides begin to stretch and trigger the urge. And by then the bladder may be so full that it’s pressing the urethra shut. Weinstein counsels astronauts to schedule regular toilet visits even if they don’t feel the urge.

“Persons with other worthwhile and challenging things to fill their time do not necessarily require bits to hold in their mouth and chew or a variety of foods in order to be productive and to have high morale.”

Animal protein and fat have the highest digestibility of any foods on Earth. The better the cut, the more thoroughly the meat is digested and absorbed—to the point where there’s almost nothing to egest (opposite of ingest).

Which beast provides the greatest number of calories for the lowest launch weight and feed consumption? To serve beef to two or three Mars astronauts, “a steer of 500-kilogram body weight has to be hauled into space.” Whereas the same number of calories could be derived from just 42 kilograms of mice (about 1,700 of them). “The astronauts,” stated the paper’s conclusion, “should eat mouse stew instead of beef steaks.”

Hydrolysis is a process by which proteins, edible if not necessarily palatable, are broken down into still edible but typically less palatable constituents. Vegetable protein, for instance, can be hydrolyzed to make MSG. Pretty much any amino acid arrangement can be hydrolyzed, including those of the recyclable that dares not speak its name.

Sometime in the early 1990s, University of Arizona microbiologist Chuck Gerba was invited to a Martian strategy workshop whose topics included solid-waste management. Gerba told me that he recalls one of the chemists saying, “Shoot, what we could do is hydrolyze the stuff back to carbon and make patties out of it.” Whereupon the astronauts in attendance went, “We are not eating shit burgers on the way back.”

Upon the occasion of history’s first manned flights—in the 1780s, aboard the Montgolfier brothers’ hot-air balloons—someone asked Franklin what use he saw in such frivolity. “What use,” he replied, “is a newborn baby?”

Contrary to popular lore, an astronaut’s blood does not boil if his spacesuit tears or his craft depressurizes. And though he would swell, he would not burst. The body functions as a sort of pressure suit for the blood, keeping dissolved gases in their liquid state. Only body fluids directly exposed to a vacuum actually boil. (As happened to a 1965 NASA test subject in a leaky spacesuit in an altitude chamber. The last thing he recalled before losing consciousness was the sensation of his saliva bubbling on his tongue.) Also, current EVA suits are designed to compensate for tears or leaks by blasting in air at far greater pressure. Bottom line: Provided he has an oxygen supply, an astronaut in a spacecraft depressurization has about two minutes to figure out what’s wrong and set it right.