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NAUTILUS education • Text Sets Science Connected EFTA00805732  NAUTIL.US I TEXTSETS Introducing Nautilus Education The modern world has placed an unprecedented emphasis on science literacy. But most existing science texts do not emphasize literacy, and most literary texts don't have science. This Nautilus Education text set pamphlet is a beta product intended to fill this gap. It contains three groups of articles from the award-winning science magazine, Nautilus, each accompanied by lesson plans and guides for teachers. Key science concepts like genetics and astronomy are explored through narrative story telling and tailor-made artwork, letting science spill over its usual borders, and waking the imagination and interest of the student. This kind of literary science classroom material was designed to helps teachers satisfy the new U.S. common core and next gen standards but have global application. The relevant standards are listed in each lesson plan. Nautilus is looking for partners interested in using and further developing this kind of content. For more information, please write to [email protected]. —Michael Segal Editor-in-Chief About Nautilus Magazine Nautilus is a new kind of science magazine. Each monthly issue tackles a single topic in contemporary science using multiple vantage points, from biology and physics to culture and philosophy. We are science, connected. 2 EFTA00805733  NAUTILUS I TEXT SETS Contents Physics Biology 4 Astronomy & Space Travel 28 Genetics & Human Health 6 Roadmap to Alpha Centauri 30 Their Giant Steps to a Cure Pick yourfavorite travel mode— Battlingarareform ofmuseulardystrophy, big,smakdark, oriwisted afamilyfindsanactivist leader, andhope BY GEORGE MUSSER BYJUDE ISABELLA 36 An Unlikely Cure Signals 12 Chemistry & Fuels Hope for Cancer How "areeptionalresponders" areremlutionizing treatmentfor the deadly disease 16 You are Made of Waste BY KAT MCGOWAN Searchingfor the ultimate example ofreeyeling? Look in the mirror BY CURT STAGER 22 Frack'er Up Naturalgasisshakingupthesearchfor green gasoline. BY DAVID BIELLO 0 O 3 EFTA00805734  NAUTILUS EDUCATION I BETA PRODUCT Astronomy&SpaceTravel How would we travel nearly five light years? This article explores different engineering solutions to the puzzle of taking a very, very, long trip, intertwining science-fiction goals with real world solutions. Students will explore fanciful applications of Newton's second law, and concepts of momentum, ions, and nuclear fusion. Lesson Plan Review vocabulary words in class. Have students read the article and answer the reading comprehension ques- tions for homework, as well as generate a discussion question of their own. In class, address any conceptual questions that the class might have. Have students write discussion questions on the board, along with the ones suggested in this document. Have students break up into small groups, each of which should address one of the discussionquestions. IS MIN Dedicate the remaining class time to completing one of the activities. 30-45 MIN Teacher's Notes: Roadmap to Alpha Centauri VOCAB WORDS Magneticfield: produced by a magnetic material or a Nuclearfusion: when two or more clusters ofneu- current, a magnetic field will push or pull a moving trons and protons collide, forming a new nucleus and charge or magnet that comes in contact with it. releasing energy. Ion: an atom in which the number of electrons and protons is unequal—thus, the atom is positive or READING COMPREHENSION negative. I. What does AU stand for? Momentum: the product of the mass and velocity of an object. 2. How fast is Voyager I moving in miles per hour? Recoil: the backward momentum from a fired gun. 3. "The engine first strips propellant atoms [typi- cally xenon] of their outermost electrons." What Plasma: one of the four fundamental states of matter, is the charge of a stripped xenon atom? composed of ions and electrons. 4 EFTA00805735  NAUTIL.US I TEXT SETS 4. What concept is at work in the ion drive? (Hint: WHERE THIS FITS IN THE CURRICULUM what is conserved?) Structure and Properties ofMatier (HS-PSI-8)Develop S. What other travel options work on this principle? models to illustrate the changes in the composition of the nucleus of the atom and the energy released 6. How much momentum does an electron fired during the processes of fission, fusion, and radioac- from a gun have? tivedecay. Forces and Interactions (HS-PS2-I) Analyze data to sup- DISCUSSION QUESTIONS port the claim that Newton's second law of motion describes the mathematical relationship among the I. Why not take a traditional rocket to Alpha net force on a macroscopic object, its mass, and its Centauri? acceleration. 2. Which of the propulsion meturds listed is most Forces and Interactions (HS-PS2-2) Use mathematical likely to succeed? Would any be used together? representations to support the claim that the total 3. Would it be worth going if it took generations? momentum of a system of objects is conserved when there is no net force on the system. 4. How far away is the next-nearest star? Engineering Design (11S-E7S1-3) Evaluate a solution to a complex real-world problem based on priori- ACTIVITIES tized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and I. Research and create a brochure or ad enticing aesthetics, as well as possible social, cultural, and astronauts to make the nip. What would they eat? environmental impacts. What psychological qualities would they need? If robots were sent, how would they be fixed? What kind of data could they expect to collect? 2. Propose another method of traveling to Alpha Centauri. ADDITIONAL MULTIMEDIA I. Voyager I Leaves the Solar System (The Guardian) I MIN 45 SEC A quick explanation of where Voyager I is, and how scientists know its location: httplAvww. voyager-I -leaves-solar-system-video 2. New Mars Rover Powered by Plutonium i)2 MIN 30 SEC An introduction to the nuclear battery on board the Mars Curiosity Rover, and the advantages of not using solar power (as with past missions): watch?v= I JOPWSztAcgEt EFTA00805736 t7 • • e O EFTA00805737  MATTER I TECHNOLOGY Roadmap to Alpha Centauri Pickyourfavorite travelmode—big small, light, dark, or twisted BY GEORGE MUSSER VER SINCE THE DAWN of the space age, a and magnetic fields of the sun give way to those of quixotic subculture of physicists, engineers, interstellar space—finding, among other things, what and science-fiction writers have devoted their Ralph McNutt, a Voyager team member and planetary lunch hours and weekends to drawing up plans scientist, describes as "weird plasma structures" beg- for starships, propelled by the imperative for humans ging to be explored. The mysteries encountered by to crawl out of our Earthly cradle. For most of that the Voyagers compel scientists to embark on follow- time, they focused on the physics. Can we really fly to up missions that venture even deeper into the cosmic the stars? Many initially didn't think so, but now we woods—out to 200 AU and beyond. But what kind of know it's possible. Today, the question is: Will we? spacecraft can get us there? Truth is, we already are flying to the stars, with- out really meaning to. The twin Voyager space probes Going Small: Ion Drives launched in 1977 have endured long past their original NASA's Dawn probe to the asteroid belt has demon- goal of touring the outer planets and have reached strated one leading propulsion system: the ion drive. the boundaries of the sun's realm. Voyager 1 is 124 An ion drive is like a gun that fires atoms rather than astronomical units (AU) away from the sun—that bullets; the ship moves forward on the recoil. The sys- is, 124 times farther out than Earth—and clocking tem includes a tank of propellant, typically xenon, and 16 AU per year. Whether it has already exited the a power source, such as solar panels or plutonium bat- solar system depends on your definition of "solar sys- teries. The engine first strips propellant atoms of their tem," but it is certainly way beyond the planets. Its outermost electrons, giving them a positive electric instruments have witnessed the energetic particles charge. Then, on the principle that opposites attract, ILLUSTRATION BY CHAD HAGEN 7 EFTA00805738  NAUTILUS EDUCATION I BETA PRODUCT momentum and push- es on whatever surface it strikes. The force is feeble, but becomes noticeable if you have a large enough surface, a low mass, and a lot of time. Sunlight can accelerate a large sheet of lightweight material, such as Kapton, to an impressive speed. To reach the velocity need- ed to escape the solar system, the craft would first swoop toward the sun, as close as it dared—inside the orbit of Mercury—to fill its sails with lusty sunlight. Such sail craft could a negatively charged grid draws the atoms toward the conceivably make the back of the ship. They overshoot the grid and stream crossing to Alpha Centauri in a thousand years. Sails off into space at speeds 10 times faster than chemical are limited in speed by how close they can get to the rocket exhaust (and 100 times faster than a bullet). sun, which, in turn, is limited by the sail material's For a post-Voyager probe, ion engines would fire for 15 durability. Gregory Matloff, a City University of New years or so and hurl the craft to several times the Voy- York professor and longtime interstellar travel propo- agers' speed, so that it could reach a couple of hundred nent, says the most promising potential material is gra- AU before the people who built it died. phene—ultrathin layers of carbon graphite. Star flight enthusiasts are also pondering ion drives A laser or microwave beam could provide an even for a truly interstellar mission, aiming for Alpha Cen- more muscular push. In the mid-1980s, the doyen of tauri, the nearest star system some 300,000 AU away. interstellar travel, Robert Forward, suggested piggy- Icarus Interstellar, a nonprofit foundation with a mis- backing on an idea popular at the time: solar-power sion to achieve interstellar travel by the end of the cen- satellites, which would collect solar energy in orbit tury, has dreamed up Project Tin Tin—a tiny probe and beam it down to Earth by means of microwaves. weighing less than 10 kilograms, equipped with a min- Before commencing operation, an orbital power sta- iaturized high-performance ion drive. The trip would tion could pivot and beam its power up rather than still take tens of thousands of years, but the group sees down. A 10-gigawatt station could accelerate an ultra- Tin Tin less as a realistic science mission than as a light sail—a mere 16 grams—to one-fifth the speed of technology demonstration. light within a week. Two decades later, start see- ing live video from Alpha Centauri. Going Light: Solar Sails This "Starwisp" scheme has its dubious features—it A solar sail, such as the one used by the Japanese would require an enormous lens, and the sail is so frag- IKAROS probe to Venus, does away with propel- ile that the beam would be as likely to fry it as to push lant and engines altogether. It exploits the physics of it—but it showed that we could reach the stars within light. Like anything else in motion, a light wave has a human lifetime. 8 EFTA00805739  NAUTIL.US I TEXTSETS Going Big: Nuclear Rockets it. "Today the closest technology we have would be Sails may be able to whisk tiny probes to the stars, nuclear pulse," Matloff says. If anything, most people but they can't handle a human mission; need would be happy to load up all our nukes on a ship and a microwave beam consuming thousands of times be rid of them. more power than the entire world currently generates. Ideally, the bomb blasts would be replaced with con- The best-developed scheme for human space travel is trolled nuclear fusion reactions. That was the approach nuclear pulse propulsion, which the government-fund- suggested by Project Daedalus, a '70s-era effort to ed Project Orion worked on during the 1950s and '60s. design a fully equipped robotic interstellar vessel. The When you first hear about it, the scheme sounds biggest problem was that for every ton of payload, unhinged. Load your starship with 300,000 nucle- the ship would have to carry 100 tons of fuel. Such a ar bombs, detonate behemoth would be the one every three sec- size ofa battleship, with a onds, and ride the blast length of 200 meters and waves. Though extreme, a mass of 50,000 tons. it works on the same "It was just a huge, basic principle as any monstrous machine," other rocket—namely, says Kelvin Long,an Eng- recoil. Instead of shoot- lish aerospace engineer ing atoms out the back and co-founder of Project of the rocket, the nucle- Icarus, a modern effort ar-pulse system shoots to update the design. blobs of plasma, such as "But what's happened fireballs of tungsten. since then, of course, is You pack a plug of microelectronics, minia- tungsten along with a turization of technology, nuclear weapon into a nanotechnology. All these metal capsule, fire the developments have led capsule out the back of to a rethinking. Do you the ship, and set it off really need these mas- a short distance away. sive structures?" He says In the vacuum of space. Project Icarus planned to the explosion does less unveil the new design in damage than you might London in October 2013. expect. Vaporized tung- Interstellar design- sten hurtles toward the ship, rebounds off a thick ers have come up with all sorts of ways to shrink the metal plate at the ship's rear, and shoots into space, fuel tank. For instance, the ship could use electric or while the ship recoils, thereby moving forward. Giant magnetic fields to scoop up hydrogen gas from inter- shock absorbers lessen the jolt on the crew quarters. stellar space. The hydrogen would then be fed into a Passengers playing 3-D chess, or doing whatever else fusion reactor. The faster the ship were to go, the faster interstellar passengers do, would feel rhythmic thuds it would scoop—a virtuous cycle that, if maintained, like kids jumping rope in the apartment upstairs. would propel the ship to nearly the speed of light. The ship might reach a tenth the speed of light. Unfortunately, the scooping system would also pro- If for some reason—solar explosion, alien invasion— duce drag forces, slowing the ship, and the headwind we really had to get off the planet fast and we didn't of particles would cook the crew with radiation. Also, care about nuking the launch pad, this would be the pure-hydrogen fusion is inefficient. A fusion-powered way to go. We already have everything we need for ship probably couldn't avoid hauling some fuel from 9 EFTA00805740  NAUTILUS EDUCATION I BETA PRODUCT Going Dark: Scavenging Exotic Matter Contrary to popular belief, Einstein's theory of rela- Instead of scavenging hydrogen gas, Jia Liu, a physics tivity does not rule that out completely. According to graduate student at New York University, has pro- the theory, space and time are elastic; what we perceive posed foraging for dark matter, the invisible exotic as the force of gravity is in fact the warping of space and material that astronomers think makes up the bulk time. In principle, you could warp space so severely that of the galaxy. Particle physicists hypothesize that shorten the distance you want to cross, like fold- dark matter consists of a type of particle called the ing a rug to bring the two sides closer together. If so, you neutralino, which has a useful property: When two could cross any distance instantaneously. You wouldn't neutralinos collide, they annihilate each other in a even notice the acceleration, because the field would blaze of gamma rays. Such reactions could drive a zero out g-forces inside the ship. The view from the ship ship forward. Like the hydrogen scooper, a dark-mat- windows would be stunning. Stars would change in col- ter ship could approach the speed of light. The prob- or and shift toward the axis of motion. lem, though, is that dark matter is dark—meaning it It seems almost mean-spirited to point out how far doesn't respond to electromagnetic forces. Physicists beyond our current technology this idea is. Warp drive know of no way to collect it, let alone channel it to would require a type of material that exerts a gravita- produce rocket thrust. tional push rather than a gravitational pull. Such mate- If engineers somehow overcame these problems rial contains a negative amount of energy—literally less and built a near-light-speed ship, not just Alpha Cen- than nothing, as if you had a mass of —50 kilograms. tauri but the entire galaxy would come within range. Physicists, inventive types that they are, have imagined In the 1960s astronomer Carl Sagan calculated that, if ways to create such energy, but even they throw up their you could attain a modest rate of acceleration—about hands at the amount of negative energy a starship would the same rate a sports car uses—and maintain it long need: a few stare worth. What is more, the ship would enough, get so close to the speed of light that be impossible to steer, since control signals, which are cross the galaxy in just a couple of decades of restricted to the speed of light, wouldn't be fast enough shipboard time. As a bonus, that rate would provide a to get from the ship's bridge to the propulsion system comfortable level ofartificial gravity. located on the vessel's perimeter. (Equipment within On the downside, hundreds of thousands of years the ship, however, would function just fi would pass on Earth in the meantime. By the time you When it comes to starships, it's best not to get hung up got back, your entire civilization might have gone ape. on details. By the time humanity gets to the point it might From one perspective, though, this is a good thing. The actually build one, our very notions of travel may well tricks relativity plays with time would solve the eter- have changed. "Do we need to send full human?' asks nal problem of too-slow computers. If you want to do Long. "Maybe we just need to send embryos, or maybe in some eons-long calculation, go off and explore some the future, you could completely download yourself into distant star system and the result will be ready for you a computer, and you can remanufacture yourself at the when you return. The starship crews of the future may other end through something similar to 3-D printing." not be voyaging for survival, glory, or conquest. They Today, a starship seems like the height of futuristic think- may be solving puzzles. ing. Future generations might fi it quaint. ,€) Going Warp: Bending Time and Space With a ship moving at a tenth the speed of light, george musser is a writer on physics and cosmology and humans could migrate to the nearest stars within a authorofTheComplereIdiot:.Guide ToString Theory(Alpha, lifetime, but crossing the galaxy would remain a jour- 2008). He was a senior editor at Scientific American for 14 years and has won honors such as the American Institute of Physics ney of a million years, and each star system would still ScienceWritingAward. be mostly isolated. To create a galactic version of the global village, bound together by planes and phones, need to travel faster than light. 10 EFTA00805741  NAUTILUS EDUCATION I BETA PRODUCT Chemistry & Fuels The matter in our world is recycled. The pair of articles here explores how elements and atoms wend their way through space and time. Students will explore how chemical reactions usher ele- ments through their journeys. You Are Made of Waste illustrates, in five short vignettes, the lives of the elements that make up our teeth, fi breath, hair,andblood. Frac* ger Up isan in-depth look at the botched promise of biofuel—energy from cars made from renewable plant growth. In the "curriculum" section of the teacher's notes, you will find information on how these pieces can help fulfill requirements of the Next Generation Science Standards. Specifically, they make for entry points to—or a means of reinforcing—lessons on photosynthesis, chemical reactions, valence electrons, and energy. But more than that, these lessons will connect to the students' daily lives, and spark discussion. Lesson Plan: Ask students to read one or both of the articles for homework. Briefly introduce or review the vocabulary words in class. Assign all or a selection of the reading comprehension questions for the students to complete along with the reading, and ask them to come up with one question for further discussion. (Note that a couple of the questions for each article are redundant.) Start class with students raising any technical questions they might have about the readings. Ask them to contribute their discussion questions, and write these on the board, along with the questions provided in the teacher's notes. Ask the students to break into small groups; assign each group to address a question, and briefly present to the class for further discussion. 30-45 MIN In the following class time (or another class) have the students complete one or more of the activities in the teacher's notes in small groups. 30 MIN Teacher's Notes: You Are MadeofWaste VOCAB WORDS Mass: a physical property that describes an object's Radioactive decay: the process by which a nucleus resistance to force. The mass of an object can be used ejects alpha particles, particles ofionizing radiation. to calculate its weight: (mass) x (gravitational force) A nucleus that does this is considered "unstable;" a = weight. substance that contains unstable nuclei is consid- ered "radioactive." This process usually only occurs in Carbon: an element found in stars, planets, comets, atoms heavier than iron. as well as in all known living things. 12 EFTA00805742  NAUTIL.US I TEXT SETS Fusion: when two or more nuclei collide, fusing to 2. How does the story change the way you see your- make a new nucleus and releasing energy. This pro- self? Others? cess usually only occurs in atoms lighter than iron. ACTIVITIES Chemical bond: an attraction between two or more I. Pick an element not discussed in this article. atoms that allows them to form a substance of defi- Where else is it found? Where did it come from? nite chemical composition. Breaking these bonds requires energy. 2. Draw a map or annotated illustration of all the places carbon goes in this article. Use outside Petroleum: a "fossil fuel" that forms when organisms research to complete a full picture of the carbon are crushed under rock and subjected to lots of pres- cycle. sure, and lots of time. Like the organisms it's made of, petroleum consists largely of carbon. ADDITIONAL MULTIMEDIA READING COMPREHENSION I. Whose air do you share? (It's OK To Be Smart, PBS) 3 m IN 30 SEC I. "Each ofthose waste molecules is a carbon atom A video that explains how we breathe recycled borne on two atomic wings of oxygen." Write out air—including molecules of air exhaled by Ein- the chemical equation for the molecule described stein himself: here. 2. "Organic" is used in two different ways in this 2. We Are Star Stuffsegment piece. What are the two different definitions? (Carl Sagan's Cosmos) 8 MIN 3. What does it mean for a chemical to be "highly Carl Sagan explains how the elements of life reactive?" Identify oxygen's location on the peri- were born in stars, evolved into simple organ- odic table, the group of atoms that it belongs to, isms, then into us: intelligent creatures, capable and why they are considered "highly reactive." of exploring the stars we came from: 4. Which elements on the periodic table are the least reactive? 3. The Microbes We're Made Of 5. "Fossil-based carbon dioxide molecules that a MIN 30 SEC We're not just made of waste. We're made of are not soaked up by oceans or stranded in the trillions of other organisms. This video provides upper atmosphere are eventually captured by a quick exploration of the microbiome crucial plants, shorn of their oxygen wings, and woven to keeping our bodies working, and what we're into botanical sugars and starches." What is the doing to kill them: process described here? (Hint: it is mentioned http:f/www.smithsonianmag. by name later in the piece.) Write down the equa- com/videos/category/3play_1/ tion for this reaction. the-microbes-were-made-of7?no-ist DISCUSSION QUESTIONS WHERE THIS FITS IN THE CURRICULUM I. "Chemophobia" is the fear of chemicals. What are ChemicalReactions (HS-PSI-2)Construct and revise some chemophobic practices or products that we an explanation for the outcome of a simple chemical engage with? Are there good reasons to be afraid reaction based on the outermost electron states of of chemicals? atoms, trends in the periodic table, and knowledge of chemical properties. I3 EFTA00805743  NAUTILUS EDUCATION I BETA PRODUCT Matter andits interactions (HS-PSI-I) Use the peri- 2. A polymer is a chainofmolecules.Identify a kind odic table as a model to predict the relative properties ofpolymer in the story, and the monomer that of elements based on the patterns of electrons in the composes it. outermost energy level of atoms. 3. Plants need carbon dioxide for photosynthesis. From molecules to organisms: structureandpro- What are some of the sources for this carbon cases (HS-LSI-6) Construct and revise an explana- dioxide? tion based on evidence for how carbon, hydrogen, and oxygen from sugar molecules may combine with other elements to form amino acids and/or other large DISCUSSION QUESTIONS carbon-based molecules. I. Why is it advantageous for companies to be Ecosystems:Interactions, energy anddynamics (HS- green? LS-3) Construct and revise an explanation based on 2. Would you pay more for gas—or any other prod- evidence for the cycling ofmatter and flow ofenergy uct, say a shirt—from a "green" company? What in aerobic and anaerobic conditions. if some of that company's practices were just as questionable as those of "dark" companies? 3. How would the world change if gasoline could be made cheaply from natural gas? Should we Teacher's Notes: Frack 'er Up consider this technology to be progress given VOCAB WORDS that natural gas has it's own environmental consequences. Ethanol: also found in beer and wine, it is a kind of biofuel that is sometimes added to gasoline for use in automobiles. Ethanol can be made from corn, ACTIVITIES potatoes, or green plants. Its chemical formula is CHICH2OH. Have students construct a timeline of fuel. Ask them to include dates mentioned from the story, Biofuel: a fuel made from plants or other organisms, and to research and add other relevant informa- in recent time. tion: like the moment in history when organisms Biomass: material from recently livingorganisms. die, the life cycle of a tree that contributed the author's container ofPrimus fuel. Organic compound: a molecule containingcarbon. 2. Draw a map or annotated illustration ofall the plac- Hydrocarbon: Made ofjust hydrogen and carbon, es carbon goes in this article. Use outside research these are the simplest kind of organic compound. to complete a full picture ofthe carbon cycle. Octane: a highly flammable hydrocarbon,and compo- 3. Write a 30-second ad convincing car drivers to nent ofgasoline. Its chemical formula is Cla n. pay a premium for green gasoline like Primus'. Catalyst: a component of a chemical reaction that Include "fine print"—side effects, or caveats—as helps facilitate the reaction, but is not used up. you see nerproiry. READING COMPREHENSION ADDITIONAL MULTIMEDIA I. "Plant biomass absorbs carbon dioxide as it grows." 1. Algae (The Guardian) What is the name of the process by which plants do An interactive slide show that illustrates how this? Look up and write down the chemical reaction. biofuels are made out ofalgae: 14 EFTA00805744  NAUTIL.US I TEXT SETS active/2008/jun/26/algae 2. Bioprospecting (TED-Ed) 4 MIN An animated video introducing the concept of biofuels, and how they could help reduce reliance on our planet's limited supply of fossil fuels: prospecting-for-beginners-craig-a-kohn 3. The Microbes We're Made Of 2 MIN 30 SEC We're not just made of waste. We're made of trillions of other organisms. This video provides a quick exploration of the microbiome crucial to keeping our bodies working, and what we're doing to kill them: http://www.smithsonianmag. com/videos/category/3play_1/ the-microbes-were-made-of/?no-ist WHERE THIS FITS IN THE CURRICULUM Matter and energy in organisms and ecosystems (HS-LSI-5) Use a model to illustrate how photosyn- thesis transforms light energy into stored chemical energy. HistoryoftheEarth (HS-ESSI -6) Applyscientific reasoning and evidence from ancient Earth materials, meteorites, and other planetary surfaces to construct an account of Earth's formation and early history. Chemical reactions (HS-PSI-2)Construct and revise an explanation for the outcomes of simple chemical reactions based on the outermost electron state of atoms, trends in the periodic table, and knowledge of the patterns of chemical properties. Ecosystems: Interactions, energy and dynamics (HS- LS-3) Construct and revise an explanation based on evidence for the cycling of matter and flow of energy in aerobic and anaerobic conditions. IS EFTA00805745  MATTER I ENVIRONMENT You Are Made of Waste Searchingfor the ultimate example ofrecycling? Look in the mirror BY CURT STAGER YOU MAY THINK OF YOURSELF as a highly refined and sophisticated creature—and you are. But you are also full of discarded, rejected, and recycled atomic elements. Don't worry, though—so is almost everyone and everything else. Carbon: Your inky nails Look at one of your fingernails. Carbon makes up carbon-rich animal tissues, finding their way into half of its mass, and roughly I in 8 of those carbon meat and dairy products. Historically, atmospheric atoms recently emerged from a chimney or a tail- carbon dioxide was mainly replenished by volcanoes, pipe. Coal-fired power plants, petroleum-guzzling forest fires, and biotic respiration. Today, one quarter of cars, and kitchen gas stoves release carbon dioxide atmospheric CO2 is the result of fossil fuel combustion, into the atmosphere. Each of those waste molecules whether it rose from smokestacks or was displaced is a carbon atom borne on two atomic wings of oxy- from the oceans. (When fossil-fuel CO2 dissolves into gen. Fossil-based carbon dioxide molecules that are ocean water, it displaces already-dissolved carbon not soaked up by the oceans or stranded in the upper dioxide derived from natural sources.) And because atmosphere are eventually captured by plants, shorn all of the carbon in your body derives from ingested of their oxygen wings, and woven into botanical sug- organic matter, which in turn obtains it from the atmo- ars and starches. Eventually, some of them end up in sphere, your fingernails and the rest of the organic bread, sweets, and vegetables, while others help form matter in your body are built, in part, from emissions. ILLUSTRATIONS BY YUKOSHIMIZU 16 EFTA00805746 NAUTILUS I TEXT SE TS 17 EFTA00805747  NAUTILUS EDUCATION I BETA PRODUCT Radioactive Carbon-14: Your pearly whites When you smile, the gleam of your teeth obscures a way into our water supply and meals. If they happen to slight glow from radioactive waste. During the late disintegrate within your DNA, they can damage your 1950s and early 1960s, atmospheric testing of thermo- genes. And many of them are bound up in your teeth. nuclear weapons scattered so much radioactive car- Unlike most of the atoms in your body, those embed- bon-14 into the atmosphere that it contaminated vir- ded in your strong, stable tooth enamel have been with tually every ecosystem and human. Several thousand you ever since you ingested them through your umbili- unstable radiocarbon atoms explode within and among cal cord and your infant feeding. If you were born dur- your cells every second as their unstable nuclei under- ing the early 1960s, you have more nuclear waste in go spontaneous radioactive decay. Some are the natu- your teeth than if you were born later, when soils and ral products of cosmic rays that can turn atmospheric oceans had had time to bury radioactive atoms. In fact, nitrogen into carbon-I4, while others result from the forensic scientists use the proportion of bomb carbon decay of unstable mineral elements that are found in in tooth enamel to determine the age of unidentified soil. But many of them represent the echoes of ther- human remains. monuclear airbursts from the Cold War, finding their IS EFTA00805748  NAUTIL.US I TEXT SETS Oxygen: Your leafy breath The oxygen in your lungs and bloodstream is a highly Oxygen absorbs electrons released by broken food reactive waste product generated by vegetation and molecules, which attract hydrogen ions, resulting in microbes. Trees, herbs, algae, and blue-green bacte- a molecular waste of your own making: metabolic ria split oxygen atoms out of water molecules during water, which comprises one tenth of your body fluids. photosynthesis. They use most of the resultant gas for An average adult carries between 8 and 10 pounds of their own purposes, but thankfully some leaks out to homemade wastewater within them, and 1 in 10 ofyour sustain you. In fact it makes up about a fifth of the tears are the metabolic by-products of your breathing air you breathe. Your cells harness oxygen to release and eating. energy from chemical bonds in the food you consume. EFTA00805749  NAUTILUS EDUCATION I BETA PRODUCT Nitrogen: Your natural curls The next time you brush your hair, think of the nitrog- Every flash of lightning and every automotive spark enous waste that helped create it. All of your proteins, plug emits a puff ofnitrogen oxide, which can dissolve including hair keratin, contain formerly airborne into raindrops and fall to earth as a form of fertilizer, nitrogen atoms. But the nitrogen in air is biologically again finding its way into food webs through plants. inert. For nitrogen to become a component of your