>> Narrator: Extreme heat, extreme cold, the unforgiving ocean, the suffocating tropics, and the emptiness of space-- killer natural environments. How can they be survived? The science of staying alive. Now, "Survival Technology," on <i> Modern Marvels.</i> <font color="#FFFF00"> [Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS]</font> >> Narrator: Cold has been a killer of armies since the beginning of time. 200 years before the birth of Christ, Hannibal marched over the Alps, and lost more than 50,000 men and elephants to a snowstorm. 2,000 years later, the Russian winter wiped out half a million of Napoleon's men as he retreated from Moscow. Hitler's troops were stopped by the Russian winter, too. More than 100,000 German soldiers suffered from cold injuries on the Russian Front. The United States armed forces weren't exempt from the cold either. Approximately 90,000 soldiers were classified as "cold injuries" during World War II. The Korean War also produced many cold-related injuries. >> John W. Castellani: Especially during the first winter that our army was involved in that conflict, there was extremely low environmental temperatures in North Korea during that time, especially up in the Chosan Reservoir, and again, there were about 10,000 cold casualties during that conflict. >> Narrator: One cold weather success story is the Native American Eskimo, or Inuit. Skilled hunters of arctic marine animals, they have thrived for more than 15,000 years in a land of bitter cold, and a feeble sun that shines only a few months of the year. Over millennia, the Inuit had no choice but to develop a cold survival lifestyle and technology. They used animal skins for clothing, because fur traps insulating air between the hairs. And they ate a diet rich in fats, which provided excess calories to warm the body. >> Dr. Murray Hamlet: They lived almost exclusively on fat and meat and very little vegetable matter in their diet. They boil the meat and dip the meat in the seal oil and eat it. >> Narrator: When white explorers came to the polar north, they tried to eat the native diet, but found they couldn't digest it. This made it hard to live and work in the Arctic, unless you could bring your own food supply. >> Sergeant John Wilson: In just about any extreme environment, a well-balanced meal can be provided, and you don't need flame. All you need is water, and you're going to have a hot meal. >> Narrator: With a flameless, ready-to-eat meal, a food pack is placed into a heat bag containing a magnesium wafer. Water is poured into the bag, onto the magnesium. The magnesium heats up, creating steam, which in turn heats the meal. This flameless meal technology is available to the general public, and you don't even need to add water. Just pull a string which breaks an internal water bladder, wait a few minutes, and your meal is ready to eat. Another major concern for the Inuit was eye damage. In a land of snow, ice, sky, and water, ultraviolet rays striking the eye from every angle caused painful snow blindness. To solve this problem, they developed a form of protective eyewear made of wood, bone, or hide strips that had narrow slits cut into it. The device was tied to the head, and the slits limited the amount of light that reached the eye's retina. Today, we use a more sophisticated form of eye protection. Modern sunglasses use a variety of techniques such as tinting and polarization to eliminate the amount and type of light that reaches the eye. Most glare comes from horizontal surfaces like highways or frozen lakes, which reflect light that is aligned in a horizontal direction. To combat this, light is filtered by polarized sunglasses because the surface of the lenses are coated with a chemical film that creates a microscopic filter that will only allow light through that is aligned in a vertical direction, knocking out the horizontal glare. As white explorers continued to penetrate the polar regions, their knowledge of how to survive in the cold increased substantially. In the 1940s, the wind chill factor, a popular phrase used by TV meteorologists to describe what the temperature and wind feel like acting together, was first determined by U.S. Army Major Paul Siple while on a trip to Antarctica. To study how wind affects cooling potential, Siple and his colleagues ingeniously set out tin food cans filled with water in the open polar air. They measured how fast water would freeze, based upon the air temperature, as well as how fast the wind was moving. They came up with a formula to estimate the discomfort felt by humans under various wind and temperature conditions. >> Castellani: If you put a person who's naked out in the environment, if there's no wind, we develop, basically, a boundary of air over our skin that helps insulate us, but when wind is placed on that skin area, it disturbs that boundary layer of air. >> Narrator: The wind chill factor is a serious threat to survival, but protection is easily found by wearing a wind- resistant outer garment that prevents the disturbance of the warm microclimate air next to the skin. Modern wind and water-resistant synthetic fabrics like Gore-Tex have pores that are 20,000 times smaller than a water droplet, and can readily keep out blowing wind and rain. Additionally, these miracle fabrics allow perspiration vapor to pass from the body to the outside environment. One of the most serious injuries that can result from exposure to the cold is frostbite. Since the 18th century, the Russian army recognized frostbite as a serious problem, and issued boots one size too large, so that they could be packed with straw during the winter. Frostbite is the actual freezing of tissue. As an extremity begins to lose heat, the cells of the skin tissue shrink as water is drawn out of them. As the temperature continues to fall, ice crystals suddenly form. >> Hamlet: It's like a bomb going off in the tissue. When that happens, it disrupts the tissues, especially the small blood vessels, so you lose the tubular integrity of the vascular system. >> Narrator: Curiously, frostbite is a condition the body imposes on itself almost as a last-ditch attempt to stay alive. >> Hamlet: When you're exposed to the cold, the body's approach is to conserve your core heat at the expense of your extremities, so you shut off blood flow to your extremities, and that blood goes to your core, and your central arterial pressure goes up. >> Narrator: A frostbite injury can be as simple as blistering that will heal, and as serious as deep-tissue freezing, where extremities can be lost. The only effective way to treat all the degrees of frostbite is to rapidly re-warm the area by submerging it in hot water. Of course, the best way to treat frostbite is to prevent it from happening in the first place. >> Wilson: In extreme cold weather environments, keeping your hands warm is a must. It's real easy to do with the use of these little heat packets. They're lightweight, they're air activated, and they slip real easily into your glove or your mitten. >> Narrator: There are two types of heat packs-- a one-time use pack that is activated by opening the package and exposing its chemical contents to air. And a second type-- a rechargeable liquid pack that's set off by an internal metal catalyst that changes the liquid into a solid, giving off heat in the process. Harsh environments like the Arctic demand survival priorities. >> Hamlet: Many people who are trapped in the cold, the severe cold, their first issue is getting shelter, and their second issue is getting water. >> Narrator: Even with all the ice and snow present in the Arctic, water is not readily available. It must first be melted and warmed before being consumed. After shelter and water, a rescue signal may be the next priority. >> Wilson: Fire works very well, but with the snow, you can take contrasting items like pine bough, logs, and you can set them out in the snow, and set out your signaling device. >> Narrator: But the newest and most high-tech of the search- and-rescue signaling devices are hand-held lasers. Effective day or night, these inexpensive, eye-safe lasers use unique cylindrical lenses that generate a band of narrow light. From an aircraft, this light can be used to sweep miles of territory, to search for a lost or injured person. >> Jim O'Meara: You're floating around in the middle of the ocean, pilot's going to look out the window and go, "Hey, there's a really strange green light." >> Narrator: The laser picks up a retro reflective surface, and flashes brightly. The laser may also be used by a person on the ground to sweep the air and signal rescue aircraft. >> O'Meara: It's the only thing where you can catch the attention of a passing jet liner at 40,000 feet. (<i> horn blowing</i> ) >> Submariner: Dive. Dive. >> Narrator: The ocean depth is unforgiving. For even powerful nuclear submarines like the Russian <i> Kursk</i> which sank in August of 2000, are not immune. The United States Navy had its own tragedy with the loss of the <i> USS Thresher</i> on a shakedown cruise in the early '60s. Congress quickly charged the navy to develop a comprehensive survival system capable of rescuing submariners trapped on the ocean floor. The<i> Avalon</i> and the<i> Mystic--</i> twin 52 foot-long deep submergence rescue vehicles, or DSRVs, were the result. Conjured from the space age technology of the 70s Apollo moon program, these craft remain operational today. >> Randell Harris: The<i> Mystic</i> and the<i> Avalon</i> have been in service for around 30 years now. Over those three decades, we have made significant improvements to its capabilities as far as search and rescue and sonar. >> Narrator: The DSRVs can be flown anywhere in the world at a moment's notice, and can reach disabled submarines in up to 2000 feet of water. Each rescue sub is made up of three high-strength steel spheres enclosed in a tapered fiberglass body. >> Narrator: The forward sphere contains the pilot and copilot and all the electronics. >> Narrator: Two other crew members handle the middle and after sphere, which are used for transferring up to 24 rescued persons from a downed sub. If a submarine goes down, it may not always land upright on a flat, smooth bottom. >> Harris: If the submarine has a 45 degree list or 45 degree up-angle, the DSRV has the ability to position itself hovering over the submarine escape hatch and land on that hatch at that extreme angle, and still make the mate, and bring the personnel on board. >> Narrator: But what does the future hold for the more than 30 year-old<i> Avalon</i> and<i> Mystic?</i> >> Gene Adgate: We expect to phase into a more modern surface-operated system. >> Narrator: Though piloted from the surface, the new craft will still have one human operator on board. It will also be easier to mate to the hatch of a disabled submarine. >> Adgate: The new system uses an articulated skirt, so the rescue vehicle stays at a zero attitude, while the skirt itself-- which is actually a mating surface-- rolls, according to many joints, hydraulically, and mates to the submarine. >> Narrator: A diver wearing a hard suit-- something that looks like a futuristic space suit-- will accompany the new rescue sub. >> Adgate: Our suit can go down to 2,000 feet. He will be there-- the first one on the scene of a disabled submarine-- to assess the submarine. >> Narrator: The hard suit is really a mini-sub, with articulated joints. The operator sits on a bicycle- like seat, and steers with foot petals connected to variable pitched propellers. The diver is able to move through the water column virtually at will. Importantly, the hard suit keeps the diver in a one atmosphere environment, protecting him from decompression sickness, commonly known to scuba divers as the bends. >> Ella Jean Morgan: When a diver descends, the pressure causes any gas that you are breathing to be absorbed into your body at a rapid rate. The problem arises when you leave the bottom and start back to the surface. If you do it slowly, the gas leaves your body, and you breathe this excess gas out with no problem. If you very rapidly come back to the surface and release the pressure, you form bubbles in the liquid of your body, and those bubbles give you a lot of problems. >> Narrator: For over a century, a cure for the bends has been to place the diver in a decompression chamber upon surfacing. The first decompression chambers were developed in the late 1800s for workers tunneling under rivers like the Thames and the East River. Even though they weren't submerged in water, the workers were still breathing regular air at great pressure, effectively forcing nitrogen into their bloodstream. Today portable decompression chambers are the latest survival gear to treat divers stricken with the bends. Lightweight enough to be carried by two people, a polyurethane gas bag is enclosed in cargo netting and capped with two aluminum ends. The diver is placed inside the chamber, which is then pressurized back to the depth they were diving at. The pressure is then slowly decreased over time to allow the accumulated gas to be released from the blood. The chamber can also be carried off to a medical facility in case further treatment is needed. Technology has not only helped people live under the sea. It has also allowed us to survive on the ocean's surface. When the<i> Titanic</i> struck an ice berg on April 12, 1912, over 1500 people lost their lives. Many of the casualties were due to hypothermia, and not drowning. >> Castellani: Hypothermia essentially is a condition that happens when the environment is such that the body loses more heat to that environment than what we can produce. >> Narrator: As the core body temperature drops, the victim becomes stuporous. As more heat is lost, coma can follow. Passengers from the<i> Titanic</i> probably died within an hour after entering the water. If the<i> Titanic</i> were to be rebuilt today, she would carry a modern life boat system. At the push of a button, a life raft package leaps overboard, trailing behind an enclosed sliding tube. Upon hitting the water, the raft inflates, and passengers drop down the slide, completely protected from the elements. Another piece of modern gear used to survive exposure in the sea is a cold water emersion suit. During the late 20s, the U.S. Navy started to produce combination flotation and exposure suits for pilots, but true emersion suits weren't fully developed until after World War II. Today, the Mustang Ocean Commander-- with its watertight zippers and seams, hood, and face seal, and inflatable head pillow-- is the state of the art in cold water emersion gear. The jungle is an extreme environment, filled with poisonous insects, oppressive heat and dense vegetation. To stay alive in the jungle takes skill and knowledge. And interestingly, some of the most effective survival technology is ancient. For decades, native Negrito instructors taught jungle survival techniques at the Subic Bay Naval Base in the Philippines. Members of an ancient race of pygmies, Negrito tribesmen survived by learning to use the jungle for food, medicine and weapons. They taught the Americans how to make fire by the tried and true method of rubbing two sticks together. A good snakebite remedy is the juice from a particular jungle grass. As bamboo is plentiful in the jungle, it can make a quick rain shelter or a bowl for carrying water. One of the more terrifying aspects of the jungle is that it is filled with mosquitoes carrying deadly malaria. In the late 1800s, it was discovered that malaria was caused by a microscopic protozoan injected into the blood from the bite of an infected mosquito. During the building of the Panama Canal, doctors learned to control the spread of malaria by destroying the breeding grounds of mosquitoes. In the Pacific during World War II, malaria-carrying mosquitoes were considered the number two enemy, after the Japanese. As the American forces fought their way through the South Pacific, mosquito eradication programs went hand in hand with rifle and bullet. Swamps were drained whenever possible. DDT was sprayed on standing pools and in native huts. If you caught malaria, quinine was the only effective means to treat it. One of the four alkaloids found in the bark of the cinchona tree, quinine was used by native populations in South America for more than 400 years, and was introduced into Europe by Jesuit missionaries. The British used quinine extensively in India, and it was the basis for their famous gin and tonics in the afternoon. The drug Atabrine replaced quinine in the 1930s and was used effectively on the troops in the South Pacific to greatly reduce the incidence of malaria. Today, Atabrine is considered to have too many side effects and is no longer used. A number of drugs have been developed to treat malaria, but malaria strains have quickly become resistant to them. Ultimately, the best cure for malaria is not to get bitten. >> Sergeant John Wilson: Your best for protecting yourself from insects in a jungle environment or any environment that's infested with insects is to protect your skin with clothing. You've got gloves, put gloves on; long sleeves, roll them down. >> Narrator: Some insects, like mosquitoes, are clearly deadly. But other insects can be eaten for food. Ants can be useful if you are hurt and immobilized in the jungle-- definitely a low-tech survival method. >> Wilson: If you're laying there, and you're sweating, you're probably going to have a lot of ants close or nearby your area, so you could reach right out and grab one. Now, you don't just want to pop it in your mouth, you want to actually squeeze the head and then put it in your mouth and just eat it right up. Tastes like a Sweet Tart. >> Narrator: One of the most basic and dangerous hazards of the jungle is getting lost. >> Wilson: Navigating in the jungle is very, very difficult. Before you actually move, you've got to take into a lot of different considerations. The capabilities of your group-- do they have the means or the capabilities of physical conditioning to make the move? Are they hurt? If you have a compass, use your compass. Once you know north, uh, you're going to be able to start orienting yourself as far as, uh, which direction to move and why. >> Narrator: Early compasses were developed in China around 100 AD They used lodestones, iron oxide minerals, as a magnetic element that would point north. Between the seventh and 12th century, lodestones were replaced by magnetic needles and compasses became common on ships. Around the late 1800s, liquid- filled casings were perfected. The liquid dampens the needle's oscillations as it swings into alignment with the Earth's magnetic field. A compass has been a trusted survival tool for centuries, but the ideal piece of high-tech orientation gear may be the GPS. >> Randy Hall: GPS stands for Global Positioning System. It's a constellation of 24 satellites that are created and maintained by the Unites States government and it allows anyone with a receiver that can listen to GPS signals to locate themselves very accurately on the Earth. >> Narrator: In the early 1970s, the Department of Defense developed the system so it could accurately locate troops and assets on the battlefield. The satellites travel in orbits 11,000 miles above the Earth, while continuously sending out a radio transmission. >> Hall: A GPS receiver needs to have at least three satellites in order to calculate a position fix. It uses a mathematical function called triangulation in order to take multiple positions and calculate where your starting from, essentially. >> Narrator: When the Global Positioning System became operational, it provided two signals, one for the military and one for the general public. The signal used by the public was intentionally degraded to protect U.S. security interests and was only accurate to within about 300 feet. But since the year 2,000, this practice has stopped, and the signal is accurate to within inches. Sometimes, survival depends on knowing where you are in the jungle, other times it's letting someone else know where you are. >> Wilson: You need to get exposure to the sky, 'cause nine times out of ten, you're going to get rescued by some sort of helicopter or by air. >> Narrator: Ultimately, because of the heavy canopy, the best signaling device to have in the jungle is a 406 megahertz emergency locator beacon. (<i> beacon beeping</i> ) The beacon sends out a radio signal which is picked up by satellites orbiting the Earth. The satellites are operated by various international agencies, as part of a worldwide distress system to listen for emergency calls from activated beacons. (<i> beacon beeping</i> ) Most airplanes and ships have them. If a plane crashes or a ship sinks, the beacons are designed to activate automatically. When a beacon is turned on, it starts to transmit a signal with a beacon-unique identifying code. A satellite immediately detects the signal and determines the distress position. It also checks the identifying code against a registration database to determine who and what is in trouble. A distress alert is then routed to the proper rescue authorities. When Saddam Hussein invaded Kuwait on August 2, 1990, the United States responded by dropping more than a half million troops into the harsh desert of Saudi Arabia. In the desert, water is the first line of defense. Soldiers under stress in desert battle conditions usually don't drink enough water. They don't feel thirsty, even though they are dehydrated. Heat casualties are the result. >> Wilson: The body needs at least four quarts of water a day to survive. We teach drink six to eight. That way they'll at least drink four quarts of water. General society is usually dehydrated, and they're used to living in a dehydrated state. >> Narrator: In the desert, a person needs at least one and a half quarts of water per hour to remain fully functional. During the Gulf War, U.S. armed forces consumed more than four million gallons of water per day. But what if you don't have any water? How do you find it? >> Wilson: Your best bet to find water in the desert is to go to old stream beds and dig down. Now, there's things that we call incidental water, which, early in the morning, condensation forms on the various vegetation around. So you could tie, uh, cloth around your legs, walk through it and gather it. You could leave, uh, your socks out at night, your tee shirt out at night. Condensation forms on it and you can wring it out. And you can drink that water. >> Narrator: If you were lucky enough to find water that's not produced by condensation, you can't just drink it. It needs to be purified and disinfected, to get rid of harmful microorganisms, like Giardia, and Cryptosporidium. >> Wilson: To properly filter your water, you're going to need some sort of filtration system, such as this straw. Some things you're looking for in your filtration system is it needs to be a .03 micron opening in the filter, itself, or smaller. Or it needs to have some sort of chemical agent released, such as iodine or betadine. >> Narrator: It's not only bacteria and microorganisms that can make water undrinkable. Salt in water is a huge problem, especially in deserts surrounded by seawater. Special saltwater filtering systems, using a reverse osmosis process, were originally developed for the military in the 1980s. Water is forced at high pressure through a membrane that is impermeable to salt molecules, as well as pathogens such as microorganisms, cysts, bacteria and viruses. Only ten percent of the saltwater passes through and ends up fresh. Once a supply of water is secured, protection from the burning sun is the second line of defense for surviving in the desert. The Bedouins of Saudi Arabia, who trace their lineage back to biblical times, have long known that clothing can mean the difference between life and death. As part of their survival technology, they developed a layering system that kept them alive in the harsh, burning environment. >> Dr. Margaret Kolka: The flowing robe of the Bedouins allows insulation. Clothing actually can keep one cool, um, in a desert environment, because there are air layers within the different layers of clothing. >> Narrator: The more layers of cloth and air, the cooler the body remains. The U.S. military's battle dress uniform, or BDU, used during the Gulf War, works on a different principle than the robes of a Bedouin. Made of a single cloth woven of nylon and cotton, the BDU depends on the evaporative cooling of sweat from the skin-- rather than trapped air insulation-- to keep a body cool. If one has unlimited water resources, the battle dress uniform is an effective way to dress in the desert. That's because sweating is the major way the body keeps cool. >> Kolka: We have a large surface area over which to dissipate heat. There'll be over three billion sweat glands on a, on a normal human body. You can secrete quite a bit of sweat. >> Narrator: Sweating does cool the body, but sometimes this heat exchange can use a little help, especially if you're fighting your way across the Iraqi desert inside an Abrams M1A1 tank. In this pressure cooker environment, tank crews need extra protection from the heat. One Gulf War solution was found in the concept of a micro- climate. >> Kolka: The microclimate cooling system is composed of a vest that receives air off of a blower in the tank. It's cooled air. And so each individual actually has his own air conditioner in a vest underneath his, his protective clothing. >> Narrator: The ordinary person, of course, isn't likely to have a desert wardrobe equipped with its own cooling system. So what<i> can</i> the typical denizen of the air-conditioned mall do to survive? >> Wilson: If you found yourself lost in the desert, probably the first thing you'd need to think about is some, some type of signal, because you want to get out of there as fast as possible. >> Narrator: If it's daytime, a signal mirror can be seen for more than 70 miles. At night, three evenly-spaced fires are the international distress signal, and will summon help. Glow lights or chem sticks are excellent for signaling. Light is given off by a chemical reaction, which takes place when a solution of glucose is slowly mixed in with an alcoholic alkaline. A glow light can last for hours, and, if twirled at the end of a string, can be seen for miles. >> Wilson: You need to conserve energy, first and foremost. Undue haste makes waste. In other words, work smarter, not harder. And that's going to set you up first and foremost for success. >> Narrator: Survival in theexp, especially long-duration missions like to the planet Mars, presents a complex extreme environment for earthbound life-forms like man. Solar and cosmic radiation, micrometeorites, the absence of gravity-- the list of problems is formidable. Not to mention the fact that in order to even get into space, you have to hit an escape speed of over 17,000 miles per hour atop a chemical-burning rocket. Early aviation pioneers, like daredevil flyer Wiley Post, knew that in order to survive in the upper atmosphere, special technology had to be developed. Post designed and used the first pressurized flight suit in the early '30s. When it was inflated, it went rigid, making it impossible to bend at the waist. The first space suit for the Mercury capsule wasn't really a space suit. It was a modified high altitude pressure suit. As space suits developed, they incrementally allowed more mobility, ultimately permitting astronauts to stoop down and pick up moon rocks. But you need more than a space suit or the protection of a spacecraft, for that matter, to survive in space. The human body is profoundly affected by two conditions of space travel: weightlessness and cosmic radiation. Each is a challenge. >> Dr. Laurence R. Young: We grow up using gravity, and we grow up developing mechanisms to deal with gravity. When we're in weightlessness and we no longer have the gravitational stresses, things become changed and they're changed not for the better. >> Narrator: The two very serious and obvious dangers of prolonged weightlessness are bone and muscle loss. >> Young: We rebuild bone every time we walk and every time we take a step, because we're supporting our body weight against the forces of gravity, and those compressive forces on the bone allow us to take calcium out of the bloodstream, build up new bone, the old bone is appropriately removed and goes back into the bloodstream. >> Narrator: In zero gravity, the compressive forces on the body are negligible, and after time, the weight-bearing bones become thin and fragile. The weight-bearing muscles also suffer. >> Young: The big muscles in our legs, the muscles that support... support us in standing upright, are the ones that we find dramatically reduced not only in size, but also in strength. >> Narrator: Arm muscles, interestingly, are less affected, as they are the prime means used for locomotion in a weightless environment. During a year-long space mission, a young astronaut could end up with the bone and muscle structure of a 70-year-old if no preventative measures are taken. Vigorous exercise is one countermeasure used on board the space shuttle and the international space station. >> Young: How do you use a treadmill in space? You have to be kept down somehow, and so there is a system of harnesses that look like a window washer's harness, and a bungee cord-- elastic cords-- that hold you down to the treadmill, and you run against that force. But it really doesn't give you the same kind of loading on all of the bones that you would get merely from getting up and walking around, as one would be in an ambulatory day here on Earth. >> Narrator: But the use of exercise equipment in a weightless environment is only a partial solution. In the future, on a three-year manned voyage to Mars, better ways must be found to protect crew members against weightlessness. Certain drug therapies look promising. >> Young: The kinds of drugs that we are looking at for preventing bone loss are the same kinds of drugs that the medical community is investigating for dealing with osteoporosis. >> Narrator: Another possible countermeasure, favored by the science fiction community, is artificial gravity. If you spin an entire spacecraft, centrifugal force will allow astronauts to live as if in real gravity. But spinning a large spaceship is not the way it will be done. >> Young: It's too expensive, it takes too much mass, and it ignores some of the serious, practical problems. However, the idea of artificial gravity, the idea of spinning a small part of the spacecraft to create a centrifugal force to substitute for gravitational force, is a very, very good one. >> Narrator: Research is pointing at the use of a small-radius centrifuge, not as a substitute for earth gravity 24/7, but as a sort of shot-in-the-arm tonic for weightlessness. Another serious problem for deep space explorers is cosmic and solar radiation. These charged subatomic particles can go through the human body like a rifle bullet, shattering cells and eventually causing cancers. >> Young: On the way to Mars, human survival depends, I believe, on some innovative new approach to dealing with the radiation issue. >> Narrator: Drug therapies, again, could be the answer. Drugs helping women deal with radiation treatments for breast cancer might protect astronauts against the effects of cosmic radiation. During solar flare activity, deep space crews can wait out the radiation storm in a small, heavily shielded bunker on board the ship. A simpler and more natural approach to this problem may be to choose astronauts who have reached the prime of their life. >> Young: There can be some advantages to flying older people in space, because after all, what ends up being of concern in development of cancer is the accumulated lifetime radiation dose. >> Narrator: Future technology for helping mankind survive in space and extreme environments is right there on Earth, rapidly evolving. For some, nanotechnology-- the making of machines invisible to the human eye out of atoms and molecules-- is where it's all happening. >> Jim Von Ehr: What we're trying to do is learn how to build machinery and materials at the molecular scale by picking up a molecule from one place, carefully moving it and putting it down precisely where we want it to go to build the... the object that we're trying to build. >> Narrator: Using a new breed of electron microscope, plans are being made to construct entire factories on atomic scales that will manufacture a variety of products. Nano medical devices are envisioned that will cruise through the bloodstream, hunting down bacteria and viruses, repairing cell damage where needed. The respirocyte, a mechanical blood cell, would make an excellent addition to any survival kit. >> Dr. Ralph Merkle: The basic idea for a respirocyte is very simple. You have a very small sphere-- a tank-- of compressed oxygen, about a micron in size, that could flow easily through your circulatory system, and it would let the oxygen out when it was needed, and absorb and compress CO2. >> Narrator: A diver taking a dose of respirocytes could hold his or her breath for hours at a time. But nanotechnology possibilities outside the body are just as exciting. >> Merkle: Nanotechnology would let you make a survival suit which would cover your skin much like a glove would cover your hand, and it would provide insulation against hot and cold. It would provide additional strength if you wanted to move. It would let you survive in a wide range of environments. >> Narrator: In a sense, the suit would be alive with complex molecular machinery constantly analyzing the environmental forces at play in. Mechanical blood cells that hold compressed air, nano medical devices that hunt down bacteria and viruses-- these are all in the realm of possibility, but not for decades to come. Extreme environments meet us with sublime indifference. We have found in them formidable opponents that we'll never conquer, but can at least survive. <font color="#FFFF00"> [Captioning sponsored by</font> <font color="#FFFF00"> A&E TELEVISION NETWORKS</font> Captioned by <font color="#FF0000"> The Caption Center</font> WGBH Educational Foundation]
