Surviving the Extremes: A Doctor's Journey to the Limits of Human Endurance (42 page)

The changes to your heart, skeletal muscles, and bones do not represent a chaotic breakdown of your body’s systems. Rather, they are the purposeful, coordinated responses of a body trying to maintain equilibrium in a strange new environment. Living in space requires only occasional exertion, so the heart weakens. Were conditions more rigorous than normal, the heart would strengthen. Spacemen barely need to walk. However, they do a great deal with their upper bodies. Hence, while they lose muscle mass and bone stock in their legs, this is not the case with their arms—much like people with paralyzed
lower limbs. These are appropriate adaptations that the body will fight to the death to maintain.

Nonetheless, a weak heart, flaccid muscles, and thin bones, while perfectly compatible with life in a weightless spacecraft, won’t be adequate once you reach Mars. Your resilient body will not readapt to a life of gravity and increased physical activity nearly fast enough to prevent you from being incapacitated once you touch down. Any treatment to reverse your adaptation to space will probably be doomed to failure because it would attempt to override the body’s most fundamental drive to survive. However, without some countermeasures while you’re in space, your body will crash on Mars even if the rocket lands safely.

It’s your turn for your daily two-hour workout on the treadmill. The small compartment it’s in smells like a locker room. The last person using it didn’t towel off very carefully; a large glob of sweat floats above the machine. You know whose sweat it is by the smell. By now you believe you can recognize whose it is simply by looking at it. You’re fed up with that astronaut slob.

And with all this exercise. You put on your harness and attach yourself to the treadmill with elastic bands so you don’t fly off backward with your first step. Other elastic bands span your knees, hips, elbows, and shoulders, increasing resistance across those joints. Lately you haven’t bothered to attach them. They make the workout much harder, and you’re already tired. No one will notice. They’re probably doing the same thing. Still nearly a month to go before you reach Mars—plenty of time to build your body back up. The exercise is boring; you quit after an hour and fifteen minutes.

Not that you need the extra time. This momentous trip has turned into monotony. At first everything was new and there was lots of work to be done. Daily instructions from Mission Control used to be exciting; now they’re irritating. Lots of things are getting irritating, such as the silly puzzles they periodically have you solve to measure mental and physical agility. And the weekly questionnaires. How many times can you check boxes about your mood, about what you think of your fellow astronauts, about what you think they think about you? Doctors
at home have no idea what it’s like. The copilot’s laugh is so annoying. The systems engineer keeps asking you for help when you just want to be left alone.

Besides being monitored by humans, machines watch over you. Sticky pads and transducers on your skin signal your pulse, blood pressure, respiration rate, and galvanic skin response—the ability of your skin to conduct electricity, which increases when there’s some salty perspiration on it, as would occur when you’re nervous. A sensor on your tongue tests your saliva for cortisol, a hormone whose level increases during stress. A pill inside you is transmitting your body temperature—you need to swallow a new one each time it passes out of your digestive tract. Some of these systems I field-tested on the NASA-sponsored expeditions to Mount Everest. There, climbers were grateful to have real-time sensors that could detect physical changes in their condition and possibly save their lives in dangerous situations. Here in space, where you feel relatively safe and comfortable, these readings are more likely to reflect emotional changes, hence the monitoring feels like a continuous lie-detector test.

The most intrusive machine of all is the face camera each of you has at your workstation. It records your facial expressions, matching the pictures with preloaded images of your various moods. The camera is programmed to detect any changes in the pattern or frequency of your expressions that might indicate emotional problems. It’s supposed to act as an early warning system. As far as you and the others are concerned, however, it’s an individual surveillance camera. More than once you have thrown a towel over the lens.

Such an act of rebellion wouldn’t sit well with ground controllers, except that they never find out. Questionnaires and performance tests are relayed back to Earth, but patterns detected by the face camera, combined with input from body sensors, are fed through an onboard computer, which analyzes the information and responds with appropriate advice. Depending on the magnitude of the problem, anything from a few words to an entire visual program will appear on the screen to engage you in an interactive dialogue. You know you’re talking to a machine, yet the instant treatment can be very effective. The computer isn’t designed to work out unresolved childhood conflicts; it’s
simply trying to get you past a stressful situation. Each time you cover the camera lens with a towel, you get a program about controlling your temper. This actually makes you feel ashamed, and you take the towel off. One time you even apologize.

Machines are ready to help with physical problems as well. A sensor is on board that can scan your entire body if you are sick or injured, and create a three-dimensional image that will be beamed back to Earth. Doctors there can rotate, enter, and magnify the image to identify your problem and prescribe treatment. If surgery is indicated, a surgeon on Earth can do it virtually, directly on the computer image, free to try different approaches and techniques individualized specifically for your condition. Once satisfied that he’s performed the best operation possible, he’ll program it into the computer and beam it back so it can be downloaded into a robot. Like a player piano, the robotic surgeon will carry out your operation—efficient and flawless, though perhaps lacking style and compassion. The system worked well in trials on Earth but, all the same, you’d rather not see how it works in space.

Your spirits lift as you approach Mars. Your tolerance and sense of humor return; you feel yourself regaining mental equilibrium. There’s renewed energy throughout the spacecraft. The crew—with one exception—seems to be coming out of hibernation, busily preparing for the Mars orbital capture now only days away. Space passengers turn back into astronauts. The exception is the doctor. He’s been spending all his time in his bunk, unwilling to treat anybody for weeks. His computer psychotherapist hasn’t helped. Neither have the messages from home, or the advice he’s received regularly from Earth doctors after he flunked that questionnaire. He takes some medications on his own plus some others you are told to give him; nothing seems to have much effect. The crew remains uneasy about his condition, but in such a confined space a formal meeting without him is impossible, so you’ve been reduced to whispered discussions in twos and threes when you think he’s asleep or on the treadmill. Everyone hopes he’ll be drawn out of his depression by the pull of Mars.

The red planet looms large outside the window, its color all the more intense after months of space blackness. So different from the
blue planet you left long ago, it’s awesomely beautiful and at the same time repellent, even terrifying. Though you’re sure the computer has detected your fear, you don’t share your feeling with the others, to whom it would only seem counterproductive. Instead you smother it with thoughts of the momentousness of where you are. Then you narrow your focus to help with the task at hand—deflecting the rocket into Mars’s orbit.

The orbital insertion proves flawless. Dead ahead is the Mars entry transition station, waiting for you for four years. It was launched during the previous period of favorable planetary alignment—along with a ground station containing a nuclear power plant. The plant has been functioning on the surface, manufacturing oxygen and water out of the hydrogen in the Martian atmosphere. Sensors have already signaled Earth that enough breathable air and fuel have been stored for the mission’s return voyage. Were this not so, your manned mission wouldn’t have been launched in the first place.

Rendezvous and docking with the transition station proceed smoothly. The station consists of two modules—a rotary engine to be attached in orbit and a descent vehicle to guide the capsule to a Mars landing. The landing won’t happen for another three weeks. Until then you will undergo preadaptation so that you can make the transition to the 0.4G of Martian gravity. The treadmill exercises, even when they were carried out strictly (which, at least in your case, they weren’t), only slowed the deconditioning that comes with zero gravity; they didn’t prevent it. You have been weightless for six months. Your muscles are weak and lazy; your bones are as thin and as prone to fracture as those of a postmenopausal woman suffering from osteoporosis. Reversing those changes will take weeks of intensive exercise and also require the introduction of artificial gravity.

After a series of space walks, the rocket fuel tanks have been separated from the capsule and the rotary engine has been attached. The engine is turned on. The capsule starts to spin, creating centrifugal force. Within the capsule you feel a pull toward the outside walls that simulates gravity. Once again there is up and down. Objects have weight. Your body dutifully adapts one more time. The adjustment proves easier here than it would be on returning home, since Martian
gravity is less than half of Earth’s. Still, the augmentation has to be done gradually, so the capsule spins slowly at first, then a little faster each day.

There isn’t enough time to wait passively for your muscles and bones to strengthen. The treadmill goes full-time now—everyone feels the need to build his or her body back up. But not the doctor. He thinks he’s fine the way he is. You try to convince him otherwise in a long discussion, during which you tactfully inform him of the crew’s genuine concern over his physical and mental health. The session ends abruptly when he says, “Tell them I’m okay or I’ll kill you.”

The physical effects of prolonged flight seem easier to cure than the mental ones. The rest of the crew feels fit, anxious to get to Mars, though they know full well that should they have a problem, there won’t be any rescue team or rehab program. As a last precaution, everyone drinks chicken soup. The high salt content draws water into the blood, counteracting the loss of blood volume. Besides, chicken soup will cure whatever ails you.

In preparation for Mars entry, the rotator is detached and the descent module connected. The fuel tanks will be recaptured and refilled for the return journey. They’ll be left in orbit for the next year and a half. There’s no place to leave the doctor.

The descent rockets fire and the capsule drops out of orbit. Mars comes up from below, spreading out under the window in ever finer detail: broad waves of red desert gouged by deep ravines and peppered over with black boulders. The ride down is surprisingly short. Retro-rockets fire, the capsule hovers momentarily, then settles down with a gentle thud. You’ve landed.

Now the capsule becomes your Mars habitat. The increased gravity is more than you experienced while in orbit so you allow a day to get used to it. The sun sets and rises. Everyone feels impatient to get going. The first priority will be to verify the on-site supply of fuel and oxygen. This will require only a short walk; the capsule landed very close to the nuclear plant. You’re scheduled to be the first one out.

You don your space suit, step into the lockout chamber, and wait twenty minutes while the air pressure gradually drops. A light goes on to tell you decompression is complete. You release the lock on the
outer hatch and pause for a long moment. You’re collecting your thoughts. Finally, you push the hatch open and the chamber fills with dull red reflected light. You’re now enveloped in Martian air, although you don’t feel any difference inside your space suit. The square hatch opening has become a picture window with an eye-level view of a vast, rust-colored desert. The harshly lit rocky rubble casts sharp black shadows against the hard flat ground: a silent, motionless, lifeless world. You put your head outside. The desert expanse reaches beyond sight in every direction, broken only by the incongruous foreground presence of the prefabricated nuclear plant and its oxygen silo.

Placing your hands outside, you pull forward to bring yourself up to the edge of the hatch frame and find you are taken aback by the resistance of your own weight. With a second effort you overcome your inertia and stand poised on the threshold. Your foot comes down heavily as you place it in the first toehold in the side of the ship. Weakened muscles make your legs hard to control. You take two more steps down to the little platform just above the surface, then turn to face outward, as befits a pioneer about to take the first step on Mars.

You are standing on a platform atop twenty thousand years of technology, the culmination of an evolutionary process that began on Earth 4 billion years ago. The first, simplest life forms, competing for survival against each other and against the environment, relentlessly redesigned and refined themselves into myriad combinations, some complex enough to conceive of and then construct their own creations. Making use of their inventions, humans have expanded into ever more extreme environments. Of the 15 billion humans who have ever lived, you were precisely positioned in the line of evolution to be the first living thing to try to survive beyond the planet.

You step off your Earth-built platform to make contact with Mars. The hard ground seems to come up too quickly against your surprisingly heavy foot. You feel a snap. A searing pain rips through your calf, and you twist and fall to the ground. You know beyond doubt that you have broken your leg.

Lying in the red desert, you’re gripped by the cold feeling that you may never see Earth again. Mars may be the altar on which you are to be sacrificed, a victim of high-tech hubris. No matter how many
wondrous inventions you’ve brought along for your well-being and protection, your body has proven too vulnerable. Its exquisite ability to adapt was never designed for export. Even though your man-made defenses have not been breached, the mission to Mars has already become overwhelming. Can your broken leg be fixed? Without a doctor? If so, will it heal? And what about that doctor, with whom you’ll have to survive for the next two and a half years? You’ve only just arrived. What next? How adaptable can your made-on-Earth body be when it’s placed on another planet? How far and how long can your will to survive carry you? One hundred million miles and three years from home, have you fallen over the edge?