Spaceship EarthPart 1: The Universe Welcome to the universe. You belong. A poet, on hearing of Newton's law of universal gravitation, wrote: "to pick a flower disturbs the furthest star." Which is true. Beause everything is connected. The bee to the flower. The flower to the bee. The rain drops to the pine needles. The pine needles to the rain drops. And you to everything, and everything to you For you are alive and aware, here, on this particular spaceship we call each, in a particular time, we call now. Just where and when are we in the here and now? Let's take a trip to find out. An imaginary trip. Did you ever lie flat on your back and stare up at the sky? You can see a long way. A long long way. Like millions of miles. And millions of years! Years ago!! As you lools up at a cloudless sky, day or night, you can see things that are not only millions of miles away, but things that happened millions of years ago. Only now is the message of light from these ancient happenings reaching you here on planet earth.
But wait! I said we look up. But where is up? To the people living on the bottom part of that globe, up is down. To the people living on the right-hand side, up is to the right. To the left-hand side people, up would be to the left, and fo the top-side people-you get the point. To a spaceship there is no up or down. There is only "into" and "away" from the spaceship itself. For us here on spaceship earth, we should say we are looking not "up" but "out." If we climb a tree, we are climbing not "up," but "away from" earth. Let's do it. Let's get into a small spaceship and move away from our large spaceship. If we do this, the first big thing we would come to as we move away from earth would be the moon. Some of you fellow humans have already visited the moon and brought back samples of rocks that they found on its surface. Let's move on. To our sun. Our nearest star. And leYs whip around that star we call sun and explore for other large objects. The first one we would find would the planet Mercury. Mercury is the planet closest to the sun. Moving further out and away from the sun we would find another planet, Venus. From our earth, Venus is the brightest object we can see in the night sky except for our moon. Venus is about the same size as earth but not as comfortable. Dense clouds of sulfuric acid blanket its surface and swirl in giant stonns in a hot carbon dioxide atmosphere. If you look at Venus through a small telescope here on earth you would see it in one of its phases. Phase means that to us here on earth only a small portion of the planet Venus is visible-that part that is facing the sun and thus reflecting the sun's light to us. After Venus, moving still further out and away from the sun we come on our own home planet, earth. Here seen in one of its phases. To someone on Mars say, a small section of planet earth would be facing the sun and reflecting the sun's light to them. We keep moving. Mars comes next. For many years people had high hopes of finding life on this planet. So far, no luck. Viking I landed on the Mars surface in 1976. For many years after it sent back once a week reports on the surface temperature and pressure, with a weekly news photo. The pictures have been dramatic, but do not show any evidence of life. After Mars, it would be a while before we got to the next planet out from the sun, Jupiter. Meanwhile, between Mars and Jupiter we would pass by many millions of small and large chunks of orbiting rocks. Astronomers call these miniplanets, asteroids. Some think that here in the asteroid belt between Mars and Jupiter we will find the most likely spots in our solar system for future space colonies. Why here? Because these orbiting rocks contain almost all the elements needed to build future spaceships, space factories, space resorts, space cities, even new space planets! Once past the asteroid belt, we would come to the great planet Jupiter, the largest planet in the solar system with its mysterious red spot. Since Voyager I and II passed by we also know that Jupiter has at least 14 moons, many of them with belching volcanoes. Next out would come Saturn, with its beautiful rings. We know now that there are over 100 of these rings, and 17 moons! The inner rings seem to be made of red ice. The recent pictures taken by Voyager II also show spokes in the rings. We are not sure what causes these spokes. The next planet out from the sun is Uranus, which also has rings, at least nine of them. Uranus is even more mysterious than Saturn. One scientist recently speculated that its surface may be blanketed with tiny diamonds. Imagine landing on Uranus not on snow skis but diamond skis. After Uranus we would find Neptune and Pluto. These last two planets in our solar system are so much further out that even through high powered telescopes they look like tiny dots. Like stars. We know that they are planets though, not stars. Like earth, they do not send out their own light. Their glow comes from reflected starlight, in this case sunlight from our own special star, our own sun. All of these planets are near neighbors in space as such things go. Though not all that near. At the speed of present day spaceships it would take us about nine years to make a round trip to Saturn, and over forty years to go to Pluto and back. Suppose we did spend the time to go to Pluto and then kegt going-as Voyager II has already done. What would we find? Nothing. And more nothing. And still more nothing. Oh, maybe a few atoms of hydrogen now and then, but pretty dull going. Despite the hydrogen atoms, around us would be a better vacuum than any we have yet created on earth. If we did keep going long enough-say about 150,000 years at present day spaceship speeds-four and a half years if we could go at the faslest possible speed in the universe, the speed of light eventually we would come to something big-another star! Would that star have a solar system? Would it have planets like Mercury, Venus, Mars and Earth? We don't know. There is a good chance. Some astronomers say there is about one chance in ten that the star would not only have planets, but that at least one of its planets might nurture life. And would that life be intelligent? We don't know. Maybe. Maybe not. Of course if there was no one home around the nearest star, we could hop in and keep going and try another. We would have many chances. Because there are many stars out there. So many stars and possible planets that we would need a good map to keep from getting lost. People in ancient times liked looking at the stars. They imagined figures in the sky, arranged in what they called constellations. They invented wonderful stories about these figures in the constellations. Taurus, the Bull .... Sagittarius, the Archer ... Aquila, the eagle ... Pegasus, the winged horse ... We don't take seriously anymore the stories, but we do still use the names for our sky maps. Here we are looldng, for instance, at a small region of the sky in the constellation of Cygnus, the Swan. Here is a parl of the constellation of Gemini, the Twins. Here is a beautiful section of the Orion constellation seen through a large telescope. It is called the Horsehead Nebula. Actually it is a huge mass of dark gas in the shape of a horse's head that blocks the light from the millions of stars on the other side. Here is another nebula. Think of it now! Every dot of light you see in this photograph is a star! Each star as big or bigger than our own star-our sun. And maybe one in ten of these stars has planets!! Here is a palt of the Milky Way band in the constellation of Sagittarius. Billions of stars! Each like our sun, burning brightly, sending out light and heat-radiant life-nurturing energy to ... to whom it may concen in this wide deep universe. Perhaps to some ancient landscape ... or waterscape ... on planets billions of miles from ours. Maybe, just maybe, enough like earth to say hello? We don't know that. It's fun to speculate though. And it's fun to find out. Here on Kitt Peak in Arizona, for instance, is the largest assemblage of telescopes in the world. Here and at hundreds of other telescope sites around the world astronomers work studying the heavens and taking some of the photographs you have just seen. We are no longer restricted to the mountains of earth for telescope sites. Here is the newest and most powerful of our tools for learning about the universe, the Hubble Space Telescope. Unfortunately, a serious flaw in its mirror was not discovered until after its launch. Despite the flaw, however, it is already sending back data about the universe unmatched by any earth based telescope. Astronomers think they will be able soon to connect the mirror flaw and then we will be able to see "out" much further and much sharper than ever before. Let's get back to our imaginary trip. The universe is so vast we have barely begun. So far we have been cruising through nebulae and constellations, finding billions of other stars like our sun, and perhaps billions of planets like our earth. All of these objects are a part of a much larger thing that astronomers call a galaxy. In this case it is the Millcy Way Galaxy. Our galaxy. We can't really get outside our Milky Way Galaxy to see what it would look like from "outside" but we think it would look something like this. A disc shape with most of the stars concentrated toward the center. From another angle it might look like this. We do know that our star, the sun, is a medium sized one out toward the edge of one of those pin-wheel like rays. All of the stars and planets in this galaxy (including of course our own sun and earth) move around in the galaxy like a giant spinning top. Consider for a moment how complicated and interesting this matter of moving can get. On earth we are spinning around on our axis every twenty-four hours. We are also moving in a giant orbit around our sun once every 365 1/4 days. With the sun and the other planets, we are also circlng in the disc of the Milky Way Galaxy. And as one small part of the Milky Way Galaxy, we are moving through dark space. Through nothing.... and still more nothing ... and again, more and more nothing ... And if we moved in our imaginary trip outside the Milky Way Galaxy and kept going, this is what we would find for a very long time. Moving at the speed of light, we would have to keep going for over a million years before we would be rewarded by finding something. Another galaxy! The nearest other galaxy to our Milky Way is the Great Galaxy in Andromeda. With the naked eye you can just barely see this galaxy as a tiny hazy spot. Through one of the large telescopes it looks like this. And then again, if we had the time-million of years more would be needed-we could go on to find othet galaxies. Remember, too, that other great mystery. This huge galaxy, which has within it billions of stars, constellations, nebulae, planets, and we know not what, is so far away from us that what we are seeing here is the way it was millions of years ago. This is because it has taken the light we see here, fast as light moves, a few million years to get from there to here. So what we are seeing is not only the far away, but the long ago. The long long ago. Here is another galaxy. Far away and long ago. Here in one telescopic view, we see not one, bur five galaxies. Each galaxy millions of light years away with only now the light reaching us to report on what happened millions of years ago. Here are still more galaxies .... many more galaxies. This is a very small section of the night sky, showing in one view dozens of galaxies. Here is another view of the night sky. Each bright dot there is a galaxy of its own, each galaxy with billions of stars making up what we see as a single dot. Billions of galaxies, each with billions of stars, each billions of miles apart and billions of years ago! And every second of every day of every year moving still further apart! ... The mind boggles. And how many of the these billions multiplied by billions have planets where right now, someone is wondering if you exist? We may never know. Or we might. Robert Frost once wrote that "poetry begins in delight, and ends in wisdom." The same thing could be said of science. Part 2: The Biosphere There are billions and billions of stars out there. One of them is our sun. Our sun moves in a galaxy like this one, out near the edge. For the past four or five billion years a small planet has been moving silently and surely around that sun. Planet earth. Spaceship earth. Looked at this way from a human-made spacecraft, we can see how whole, how together and how beautiful our planet is. Moving in closer we recognize more familiar views-patchquilt fields, roads, farmhouses, automobiles. From an airplane it looks like a child's play world. Closer in, it becomes a wonder-world-a piace to see, to explore, to learn in and to take care of. The only catch is this spaceship did not come with a set of instructions. Imagine the details of engineering, the libraries of technical information, the genius of intelligence and skill that goes into building and operating a modern human-made spacecraft. Earth, too, is a spacecraft. One that orbits the sun canying a precious cargo of living things. It has been carrying this cargo for a few billion years. Only now are some of the living passengers, human beings, beginning, barely beginning to get the hang of operating this spaceship earth. Consider the compartments of our human-built space shuttle. The oxygen supplies, the water supplies, the food and waste disposal systems, the power plants, the computers, the intricate navigating and operating controls. All these systems are carefully and ingeniously fitted into a small space. The compartments of earth are roomier. They are even more carefully and ingeniously fitted together. Here's what one kind of compartment looks like. A city. Human-made. Complicated. Exciting. Lonely. Romantic. Brutal. Fascinating. Here is another kind of compartment. A small town. A village. The kind of compartment where most of the world's people live. And then there is the countryside. The farms, the plains, the mountains. ... The lakes, the oceans, the deserts. ... The broad sweep of the earth and wide range of living creatures who inhabit it. All these compartments with all the passengers are powered by the sun. All these compartments and passengets are parts of what we are coming to call the BIOSPHERE. BIOSPHERE means living sphere. It includes all the living that goes on in the thin outermost layer of planet earth. The biosphere includes not only all living things, but also all the non living things involved in living, a few hundred feet down into the earth, and a few hundred feet out away from earth. The biosphere is the part of spaceship earth that interests us the most because it is the part that we are a part of. How does it work? How do the parts of the biosphere mesh? How do they cooperate? How do they compete? What makes them change, evolve or break down? As in a human-mahe spacecraft, every part has a connection to every other part. Unlike a human-made spacecraft, many of the details of the spaceship earth connections are unknown. High African plains with herds of wildebeest, zebra and prides of lion ... sea-level beaches with flocks of gulls, sandpipers, and sunburns ... mountain meadows with aspens, hawks and sunday hikers ... city plazas wfth fountalns, statues, and conventioneers. How do they all connect? Even though our spaceship did not come with a set of instructions, scientists of yesterday and today have figured out some of the connections and some of the operating rules. Here is a rough outline of what we have figured out so far. There are four main parts to the biosphere. Abiotic. Producers. Consumers. Decomposers. They are connected to one another in a continuous cycle. One part changing into another part, over and over again. Let's take them one at a time. The abiotic first. Abiotic means not-living. In the biosphere the abiotic includes rocks. Big rocks, little rocks, crushed rocks, minerals, sand, dirt. Included also in the abiotic is air, a mixture of non-living gases. Air is approximately four-fifths nitrogen, one fifth oxygen, with a scattering of small but important amounts of other gases like argon, carbon dioxide and water vapor. And finaily, the abiotic includes water. The atoms that make up the abiotic rocks, air and water do not stand still. These atoms are continually on the move, circulating around and around, on their way into and out of the other three parts of the biosphere-the producers, the consumers and the decomposers. We should put it more strongly. These atoms don't just go into and out of these other parts-they make up the other three parts. All life, in other words, is literally made of atoms from rocks, air and water. These rock, air and water atoms become the living part of the biosphere by way of what we call PRODUCERS. Producers are for the most part the green plants of the world. Corn, grass, trees ... seaweeds, pondweeds, algae. The atoms that now make up, that are the corn, the grass, the tree the seaweed, the pondweed, the algae, are the iame atoms that a few hours before made up the abiotic level of the biosphere. That were rocks, air and water. Think about that a minute. It's quite a trick you'll have to admit. The producer plants are able through their chemical magic to change rocks, air and water into leaves, fruits, and nuts. Into the smell of the rose, the taste of the apple, the strength of the two-by-four. Of all things in the world, it is only the green plants that have learned how to do this trick. Scientists have figured out some of the details of how they do it. They call the process of changing atoms of rock, air and water into molecules of living plant material, photo-synthesis. Photo means light. Synthesis means putting together. The energy provided by sunlight powers photosynthesis. Green producer plants can use this power to synthesize-put together-abiotic atoms from air, rocks and water. They rearrange these atoms and make them into roots, stems and leaves. Into fruits, vegetables and seeds. These roots, stems and leaves now become food for the next level of the biosphere, the consumers. Animals eat the grass turning it into animal life. Fish eat the pondweeds and turn it into fish life. We eat the fnrits, vegetables and seeds-the milk, beef and fish-and turn it into human life. Of course animals are not the only living things that need food. Plants themselves use some of the living material they have just made for their own life energy and growth. We don't say usually that plants "eat" but they do consume some of the chemical energy that they themselves captured in the process of photosynthesis. In a real sense, then, we are what we eat. The same atoms that once were a part of rocks, air and water became green producer plants and now make up a consumer organism like you. Your hair and your heart, your big toe and your brain. You are a biosphere consumer. That explains three of our four parts. The fourth part is the often neglected and still not well understood DECOMPOSER. Decomposers are living things that can convert living matter back into the abiotic rocks, air and water from which they came. From which we all came. A lot you don't see is happening on the quiet earth ... and in the wet marsh. Literally billions and billions of bacteria, worms, molds and tiny fungi are working day and night to break down the dead leaves, the animal wastes, the dead insects, the dead creatures of all kinds, taking them back into the abiotic. Yes, from dust thou art. To dust thou shalt return. And so the system works, this biosphere. Powered by sunlight, the four parts move steadily one into the other. From a long time ago to a long time hence. Unless we foul up the works too much. If a spaceship's oxygen system malfunctions, there are backup systems. But if they too fail, the astronauts must die. So, too, our earth spaceship has many backup systems. But if we overload and foul them up too much and too many times, we too must die. For we too are space people. Each and every one of us. Fortunately many people are becoming more aware of this nowadays and are thinking and working and fighting to keep our air pure. To keep our water clean and clear. To keep our earth sweet smelling and fertile. Abiotic to Producer ... Producer to Consumer ... Consumer to Decomposer ... Decomposer to Abiotic ... Again and again and again. End of lesson one. Almost the end. Like all good ends, a beginning too. People are pretty powerful. Especially now that there are so many of us, and we are tinkering more and more with the spaceship. Elecctrifying it, bulldozing it, paving it, computerizing it, making it more barren here, more productive there. We'd better make sure what we know what we are doing. Winter is cold, but not so cold as earth will be if we goof up the directions. Spring is life begun again as the rains rain down. Unless it should become a silent spring. Summer is Iush and green and lovely. Fall is golden and sad-happy. Will they both come again and again and again? Yes. If, as we sit and stare and wonder, we give a thought now and again to just where we are. Part 3: Living Things There is a beauty in stars and in the great spaces between stars. There is beauty in water, drops of it, oceans of it-and in air, blue as blue as far as the eye can see. And there is beauty in rock. Cold, hard rock. There is even more beauty in the eye that sees these things; the heart that feels them; the intelligence that understands them. Understands them enough to explore, to learn and to create new things. As an astronomer once said, "it is not the immensity of space that should command our wonder, but rather the man who measured it." What about the dog who loved the man who measured it. What about the tree that grew the wood that made the house to shelter the man and the dog? In other words, what about living things? All living things-pretty unusual things in this wide deep universe. Things that can create order out of chaos. Things whose business it is to create new meanings, new possibilities, new wonders. Perhaps there are other spots in the universe where you might find spring blossoms like these. We don't know about them yet. As far as we do know for sure, only spaceship earth has a rich combination of living things. Like these zebras and wildebeests migrating cross an African plain.... Like these tropical fish in a Caribbean coral reef.... Like these alligators in a slow-moving Florida river.... Like this hawk scaring over a rocky hilltop in Illlnois. Lions and leopards ... water buffalo and eagles ... deer and giraffe. Lowly moss and lichen that can Ilve on bare rock ... pondweeds and trout... lobsters and sharks ... apple trees in spring blossom ... maple tree in summer glory. And of course we haven't even begun to call the roll of this modern Noah's ark. What about the millions-correction -billions on billions of bacteria, molds and other microscopic living creatures that live in every handful of soil and every drop of pond water. In many ways these microscopic living things are the most important passengers of all on spaceship earth. Without them the plants and animials we see around us would never have evolved on earth in the past, and could not exist on earth today. Today all of us together do live on spaceship earth. All of us together are passengers on a large chunk of rock circling a medium sized star somewhere out near the edge of the Milky Way Galaxy. Nothing really very special about our address in space. In a universe that is mostly hydrogen,the simplest of all the elements. The very thin cloud of hydrogen that fills what we call space is dotted occasionally by a denser concentration of hydrogen and few other simple atoms. We call this denser concentration a star. There are billions on billions of these stars. Once in a very great while, we might find a lonely spaceship not unlike earth orbiting one of these stars. A planet like earth able to use the light of one of these stars to produce change a few simple chaotically careening, buzzing, booming atoms ... Into things like this ... And this ... And this ... And this ... Or this. Yes, living things have done these last things too, human living things. Let's take a closer look now. What does it mean to be a living thing? Or is 'thing' the right word? Perhaps we should say what does it mean to be a Iiving event? Buckminster Futler said of himself "I seem to be a verb." This makes sense. Life is not a thing. Life is the living. The process. the event. What is this living event all about? Here is one way of putting it. To be living means to create order out of chaos. To reverse entropy. What does 'entropy' mean? It means chaos. Disorder. The waY your room is after you haven't straightened it up for a week. Everything all mixed up. A random bumping and thumping of atoms. Living events move in the opposite direction. Cleaning up the mess. Making the random bumping and thumping of atoms turn into something neat and workable and lovely. Quite a trick you'll have to admit. Powered by the sun, given a couple of billion years, this small spaceship has been father and mother and cradle and home to many creations. Not the least of which is the human race. A race, which, despite its faults, despite its sometimes catastrophic mistakes, its ignorance and weakess and at times unspeakable cruelty. Despite all the worst things you can cay about humankind, in the short time as star time goes that we have been around, things have happened. New orders, new meanings, new beauties have blossomed in this corner of the universe. And what about tomorrow? The space visionary, Constantine Tsiolakovsky wrote a hundred years ago, "earth is the cradle of the mind, but one cannot live in the cradle forever." Who knows what new meanings will be created tomorrow as we, for the first time, venture a short distance away from our mother ship into the near reaches of outer space. Or, who knows, perhaps the biggest surprises outer space, but rather in the near reaches of inner space. That special space where poems are written, where experiments are thought of, where wonders are wondered, where new worlds are imagined and where events are understood. How do they do it? Living things, that is. How do they manage these tricks? In all this empty space, how do living things manage to create order, to reverse entropy? There are many mysteries here, as well as some partial answers. Looking at the big picture, let's just say that in the here and now, as far as we can tell, there is air, and there is water, and there is rock. Using the atoms that make up air and water and rock, green plants with the aid of the sun's energy can make food. Green plants can reverse entropy and make life itself. Their own Life. They do this in a process called photosynthesis. Animals then come into the picture. Animals eat the plants and in a process called respiration use that sun-captured energy to make their own order. Other animals eat animals and we have still more new events. And some living things, especially human ones, can not only make their own living seIves, they can make extensions of themselves. Extensions of many kinds. Extensions of great power. Extensions of great delight. Now for each of these living events to do this, they have to have some interesting insides and well as outsides. These insides can be very intricare and complex. In different creatures they can be very similar and very different. You may want to study later the details ofjust how certain of these insides circulatory systems, digestion systems, nervous systems-how they actually do their work. How, for instance, does an apple tree convert air and water and soil into new buds, new leaves, new flowers, new apples? How, specifically, does a Lion convert his zebra prey into lion eyes, lion claws, lion ears and lion mane? How, specifically, does a human convert his bacon and eggs and daily experiences into growth and talk, into spaceship and experiments, into poems and adventure. And into babies. Yes, babies. No matter how good living things are at creating new events, whether these events are apples, lions, spaceships or poems, living things die. Luckily,they have found a way to get around this too or else the adventure of life on this spaceship earth would long ago have come to and end. They get around death by having babies. More living things just like themselves. Correction. Not just like themselves. A little different. Just a little different. And from that Little difference comes in time big differences. From amoebas to whales, from insects to humans; the amazing variety of life on this small spaceship has all come out of these small differences of parent to child, multiplied over many millions of years. Scientists call this process of change over long periods of earth time, evolution. Who knows what differences are yet to come. A small step for man, a giant step for mankind. What new meanings will we create for ourselves, for our spaceship and for all its passengers in the years and in the millennia to come? More important, what new meanings will you create for yourself, for your spaceship, and for your fellow passengers in the hours, the days, the years to come? A good beginning might be the place the great scientist Albert Einstein pointed to when he wrote, "The mysterious is the source of all the art and science .. that mysterious harmony of nature into which we are born." Part 4: The Cell "Oh, Venus was born out of seafoam
Goddesses today may be assembled upon assembly lines, but people aren't. How are people assembled? What makes each one of us people individually human? What makes each one of us so alike and so different from every other human being who has ever lived? One kind of answer to this question would be to 80 back and see how a person gets his start in the adventure we call life. If we do this, we find that you get your start pretty much the same way a fish or a frog or an elephant gets its start. From a single cell. A fertilized egg cell. These happen to be salmon '88s. Each one, each orange globe there, has been formed from the combination of a single celled sperm from the male salmon, and single celled egg from the female salmon. Given time and the right environment, each egg will grow and turn into a small fish. Here are some fertilited eggs of an insect, enclosed in a kind of shell and laid on the underside of a leaf. You, too, started your life as a fertilzlled egg. You had better protection and less company. Here is what you would have looked like at age one minute. One minute after you were conceived from a combination of your father's sperm cell and your mother's egg cell, Under a microscope this is it! (you could hardiy be seen at all with the naked eye.) One cell. You. How is that tiny little blob of a microscopic speck going to find its way into becoming a full fledged human being? Here's how. It starts to divide in a few hours. Now you are two cells. Two cells that stick together mind you. Then the two divide again, and you are four. Four that stick together. The four become eight; the eight, sixteen; the sixteen,thirty-two; sixty four; a hundred-twenty-eight; two-hundred fifty-six .. at this very early age notice the hundreds of cells are allpretty much looking alike. Alive, but at this state, impossible to tell whether they will turn into a human being or a fish being. Before a month goes by, however, look how you would look. As the number of cells coming from that first fertilized egg gets into the thousands and millions and billions, a fantastically remarkable thing happens. Cells begin to specialize. In order to try out different jobs, different kinds of cells form. And these different kinds of cells group themselves together indifferent. kinds of ways. Now you have the beginnings of eyes and ears, or brains and hearts, of skin and hair. And not just any eyes and ears and brains and hearts and skin and hair. But very unique eyes and ears and brains and hearts and skin and hair. Your eyes. Your ears. Your brain and heart and skin and hair. And finally, wonder of wonders! All of these cells end up as a unique human being. Built not out of plaster and paint and glue, built out of billions on billions of individual cell building blocks. All working together to make a person the likes of which the world has never before seen, and will never see again. The next time you walk in a large crowd think of that we are all, each one of us, so alike as human beings, and yet so very different as individuals. But then so is each horse a unique individual horse. Each cow, a unique individual cow. Each dinosaur was a unique individual dinosaur. Each tree, each flower, each humble weed, a unique tree, flower and weed. And in every case, they get their individual start from a fertilized egg cell. Let's look a little more closely now at individual cells and cell parts. For yes, cells are themselves complicated thfngs that have many parts. Suppose, for instance, you looked at some of the cells making up a tree tunk under a microscope, The rings are made of many cells organized together like little bricks. If You were to take some of the special xylem cells that conduct water up from the roots to the leaves and examine them still closer under a high power microscope and with special staining dye, you might see this. An actual photograph of a strange new world. Structures within structures. And the more you magnify the more wonders you find. Take one of your bones. Take a microscopic slice and you would see cells again. Bone cells with calcium mineral deposits around them. Laid down wer so carefully and precisely by the bone cells themselves. Scrape a little tissue from the inside of your mouth. You would see cells like this. Lining cells that look like they are floating here in a starry ocean. Suppose we do take some cells from the real ocean. In a drop of ocean water we might find cells that look Like this. A diatom. In this case a single cell that is complete in itself. A whole living thing in just one cell. A Iittle glass house that holds within its walls an incredible amount of complexity, order and power. Consider. This one-celled diatom can, in that small space, eat and digest and burn food, can direct its own movement and get rid of wastes and respond to the sun ... and can reproduce. Here is a large sampiing of many different kinds of one-celled cratures. How in the world can they do so much with so little! What goes on inside those microscopic membranes? One way to think of it would be to liken it to a city. Think, for instance, of all the kinds of things that go on in a city day by day. The making of electricity; the construction of buildings; the transporting of people and materials; the disposal of wastes; the maintaining of order; the manufacturing of goods; the education of children; the transmission of messages; the whole works, the city works. Inside each cell there is a kind of city. A minature city with structures built up by itself to do all the things a big city does and more. Here is an artist's diagram of just a few of the parts that all cells have to do their work. They all, for instance, have to separate themselves off from their surroundings with some kind of cell membrane. They have to become a walled city, with an inside and an outside. Inside, almost all cells have a nucleus, a dark-looking spot. Inside the cell nucleus, when we focus on it, and magnify, we find structures called chromosomes. The yellow-colored strands you see here. We might liken the chromosomes to the mayor and the city hall and the police chief and the jail and the school board all roIled into one. And when we magnify the chromosome still more, using special x-ray techniques, we find that the most essential part of the chromosomes are large molecules that might look like this. Biologists call these spiralling molecules DNA, deoxyribonucleic acid. DNA, we know today, is the master life molecule. The molecule that has in its spiralling atoms, the information that is needed to make a tree a tree, and to make you you. When a cell divides, something must tell it how to do it. And do it with no mistakes, please. That something seems to be in the spaghetti-like chromosomes here, with their powerful DNA strands. Besides reproducing, the cell must stay alive. No easy job. This means for one thing that certain materials must constantly be brought through that cell membrane and other materials must be sent out. It means that these incoming materials must be disassembled and then rearranged into life molecules. It means that some of these molecules must be burned to provide energy to stay alive. It means that ceaseless organized activity must go on every moment of every day of every life. To appreciate this better, try this. Imagine a city you know. Reduce it to cell size and fit it inside a wall. Now imagine all the activities that go on in the city, going on inside the cell. Let's add one more idea now. Perhaps it's not an accident that we all seem to have a certain fascination with water, especially with ocean water. We seem to be intimately related to ocean water down at that basic cell building block level. Inside each cell in our bodies we have not only a miniature city, we have a very wet city. A city under ocean water. It was only a very short time ago as the universe counts time (a few billion years to be exact) that one of its small spaceships, planet earth, somehow got caught up in an interesting new idea called life. Spaceship earth had been circling a medium sized star out near the edge of the Milky Way Galaxy for a long time before that new life idea was to come along and take hold and eventually to dramatically transform the small spaceship itself. Out of the most common things-air, water and rocks-life began. And from these most common beginnings life in cells seemed to be the way to go. Get together the right ingredients, surround them with a wall or membrane, bring inside the salty ocean water, and start living. It wasn't that simple of course, but it did happen and today, a few billion years later, every last cell of every last living thing that has ever lived, is now living, or will ever live in the future, gives testimony, to the power of that architecture. For in a very real sense, every last cell of every last living thing has descended into a direct line of succession from these first cells in the ancient ocean. And our cells, too, like those ancient ocean cells, are able to stay alive today by keeping an ocean inside. By bottling up, so to speak and building our own unique watery cities inside. Watery cities whose ancient salty ocean water you are able to taste every time you cut your finger or shed a tear. So when you see a bird soaring into the air give a thought to the billions of watery cities inside that bird that are its ocean-bathed cells. And when you have that thought save a little of the wonder for yourself. For the ocean inside you-an ocean that is special only to you. A dancer, Martha Graham, put it this way. "There is a vitality, a life force, an energy, a quickening, that is translated thfough you into action. And because there is only one of you in all time, this expression is unique. And if you block it, it will never exist in any other medium and be lost. The world will not have it." Part 5: Atoms and Molecules Have a drink. Do you know what the water you just drank is made of? Atoms. Hydrogen atoms and oxygen atoms to be exact. Put together in a water molecule. Billions of them in one swallow. Here is an artist's picture of what a single H20 molecule might look like if we could see it, which, of course, wecan't. Even with the most powerful microscopes today we can't see atoms. They are just too small. Let's try an imaginary experiment to see just how small atoms and molecules are. Take a glass of water and somehow mark each water molecule so that you could recognize it if you ever cameacross it again. Now you pour all of the marked molecules down the sink. Let's follow them. If you live in a city or town, the water molecules will mostly all go through the sewer pipes where they will mix with other waterand waste molecules from hundreds, thousands, maybe millions of other sinks in your city. After the purification processes are finished, your water molecules will go out into a river and eventualiy down to the sea. Some of them may be taken up into the air by evaporation and carried far off by the wind. Some will be taken up living insects, plants, fish, people and become a part of insects, plants, fish and people. For the sake of our imaginary experiment thoughlet's assume in this case that all the water molecules you poured down the sink eventually get distributed evenly into all the oceans, lakes, rivers and ponds of this world. Comes the surprise! Down to an African marsh lumbers a giant elephant. He puts his trunk into the water and gives himself ashower bath. He is washing himself with over 200 of the water molecules you poured down that sink! He isn't that special. In a chilly northern Wisconsin lake your dog dives off a pier to fetch a stick. She swims through a fewhundred of the water molecules you poured down that sink. And on spring vacation your brother jogs along a beach in Florida, his feet washed by the Atlantic Ocean. His feet would pick up a few hundred of the water molecules you poured down that sink. In other words no matter where you go on Spaceship Earth you could not escape. You would always, everywhere find some of your marked molecules. Almost unbelievable but true. Atoms and molecules, a new world of small size and large numbers. A world where many of our common sense notions about stuff no longer apply. We can smell pine trees, we can kick rocks, we can swim in water, but when we magnify far enough, when we look inside deep enough to see just what pine trees and rocks and water and our own looking apparatus are made of-mystery. Are they really made of these super tiny, super plentiful mysterious little miniature solar systems? Solar systems that are themselves mostly empty space? Yes. Apparently they really are. I need to make one correction here. Scientists used to think the atom inside was constructed somewhat like a miniature solar system. New evidence has shown this picture to be false. Today the inside of the atom is pictured instead as a very tiny nucleus surrounded by clouds of electrons. Whatever it does look like inside (and perhaps it doesn't even make sense to ask what something we can never see, looks like) still we do know that everything in the world is made of atoms. Everything.
Simple things like air and water. Complicated things like spring wild flowers and the camera that takes these pictures, the eye that sees them, and the brain that understands them. The idea of atoms is not new. The very first real scientific thinkers in ancient Greece made up the word "atom" and the idea it stood for. They said that the world was made of four basic kinds of atoms-air atoms, earth atoms, water atoms and fire atoms. They called air, earth, fire and water the four elements. A tree, for instance, was made of some kind of subtle combination of these four kinds of elemental atoms. Each element itself is a particular kind of atom, always the same in itself, but rearranged over and over again into new combinations. When a tree decays, they said that the earth, air, water and fire atoms were not destroyed, just recycled. Around and around and around. Birth, growth, death, decay. Leaves budding, leaves falling, generations come and generations go. The atoms live on. And they were right. Atoms do make up everything that exists. Atoms do cycle around and around and around, into and out of air, earth and water without themselves being destroyed or created. (They were wrong about fire being an atom. Fire, it turns out, is not a thing, but a happening, a way that atoms behave.) And they were right that the things made of atoms include you. It is hard to believe isn't it? When you look at and feel your finger, you are looking at and feeling a buzzing swarm of atoms and molecules. Even more astounding, the things doing the looking and the feeling, your eyes and your brain, are themselves made of atoms and molecules. The other mistake the Greeks made was in saying there were only four elements. Today we know there are over one hundred elements, each element itself made of a particular kind of atom. Here you see all the kinds of atoms listed in order in what is called a periodic table of the elements. You could call this chart a kind of master list of basic parts. All things are made of some combination of the kinds of atoms listed on this chart. Water, for instance, instead of being a basic element as the Greeks thought, is a molecule made of two kinds of basic atoms-hydrogen atoms and oxygen atoms. These atoms are put together in a water molecule, two to one. Two atoms of hydrogen to one atom of oxygen. H2O. Air is not an element either. Air is a mixture of gases. Four-fifths nitrogen, one-fifth oxygen with traces of other gases. Earth has all the rest of the elements, except a few that humans have made in the laboratory. Earth has metal atoms like iron, aluminum, copper, tin, uranium and gold. Earth has essential life-building elements like nitrogen, sulfur, phosphorus, sodium, chlorine and carbon. Here again is the complete list. Some kind of atoms are rare, some kinds are plentiful. The plentiful ones are Ihe ones most involved in making living things. These 30 to 40 life-important elements, basic kinds of atoms, circulate around constantly into and out of the air, earth and water, making for a very active richly furnished spaceship. In the universe as a whole over ninety percent of the atoms are the simplest possible one-hydrogen. Though it is a better vacuum than any we have ever created on earth, space is not empty. In a cubic foot of 'space" you would find a few hundred hydrogen atoms. And therr is a lot of space out there. In that plentiful space you do find concentrations of atoms that we call stars. Stars, too, are mostly hydrogen. But the hydrogen in stars is in violent motion releasing energy and creating larger atoms in the process. Once in a long while a star wili explode and spread some of its atoms, small and large, far and wide into the space around itself. And once in a very long while this star dust will find itsell clumped together into chunks we call planets. Not too close, not too far away from a parent star. Chunks like our own spaceship earth. On these well-placed planets star dust eventually finds itself made into hands and brains of creatures called human who in turn learn how to put other remnants of those starry explosions to work. How to take nitrogen atoms out of the air, for instance, and make them combine with hydrogen and other atoms to make fertilizer for corn fields. Or make them combine in other ways to make fireworks for Fourth of July celebrations. How to get iron atoms from rocks, make them fuse together to form steel beams or railroad tracks. How to get aluminum atoms from clay, make them fuse together to form airplane wings and motors, or strong thin power lines. How to get tungsten atoms and make light bulb filaments. How to get silicon, oxygen and a few other rare atoms to blend together to make plaster and cement ... and glass fibers and computers. How to And and take out uranium atoms from rocks and make bombs or electric power plants. The Greeks were indeed right. Everything is made of atoms. The whole trick of modern chemistry is understanding the atoms listed on this chart. Understanding them well enough to make them do the tricks we want, and to bring us some surprises along the way. Example. In our laboratories we are learning how to rearrange atoms into ways that will be useful in carrying messages, solving problems, curing disease, enhancing beauty, building wealth and prolonging life. We can hook up carbon and hydrogen atoms in a line as in this molecular diagram. Here we would have one kind of useful material that you could burn in your automobile as fuel. Add a few oxygen atoms and hook it up in a slightly different way and you get a very different material-synthetic rubber. Hook in a still different way and you get a useful fiber, nylon. In a much more complex way nature has formed giant molecules like this-DNA-deoxyribonucleic acid. DNA is the basic life molecule. The molecule that caries the directions necessary to make a tree a tree and to make you, you. Very recently chemists have learned that carbon can hook to itself in a whole new way, in the shape of a soccer ball. They call this new molecule a "buckyball." In the next few years there will no doubt be thousands of new molecules based on this way of hooking together. Who knows what new kinds of materials, new kinds of drugs, new kinds of fabrics, lubricants, paints, and machines may come from this new knowledge. Whether the materials are made by nature or by the natural creatures called human beings, the result is the same-atomic materials. Everything is made of atoms. Atoms are not created or destroyed. They are continually rearranged. The eye that sees this, the brain that understands it are made of the same atoms as the things seen and the things understood. Yes, there are some mysteries here. The kind that Albert Einstein was thinking of when he talked of the "mysterious harmony of nature into which we are born." To help touch these mysteries Iet's trace the travels of one atom from long ago until now. Let's start with a carbon atom, tied up in a carbon dioxide molecule in the ocean of long ago. A living green plant floating in this ancient ocean takes in this carbon dioxie molecule and pulls out the carbon atom, using the carbon atom 's a building block for its own living factory. The plant cell dies and sink to the bottom of the ocean. It is covered by layer on layer of sand and silt. A few million years later it is taken out of the ground-the carbon atom is now a part of fuel oil-and is sold to a power plant where the fuel oil is burned to make electricity. Now the carbon atom we are following is sent out inlo the air as a part of a carbon dioxide molecule again. Floating with the trade winds it ends up in Africa. Taken in by a leaf of an acacia tree it becomes now a part of the leaf. Which is eaten by a giraffe. The giraffe is eaten by a lion and now the carbon atom goes to the lion's muscles where it is burned during a romp with his brother across an open field. It leaves the lion's lungs as a part of a carbon dioxide molecule again. Crossing the ocean it enters an aspen leaf and becomes part of the aspen trunk, which is cut and made into paper which is used in a classroom. Thrown in a wastebasket, the paper is later buried in a landfill. Now what happens? The carbon does not die. It is taken up by decay bacteria which change it into carbon dioxide and send it back into the air or water or soil ... maybe back to a single celled floating plant in the ocean. Do you see what we mean by atoms not being created or destroyed? From the beginning of this planet they are merely rearranged into one thing or another. And if you remember how tiny and how plentiful the atoms were in that first glass of water, perhaps now you can appreciate another striking mystery. You undoubtedly have within your brain at this moment some of the very same atoms that were in the brain of Julius Caesar or Abraham Lincoln or Marie Curie or Martin Luther King. Pick anyone you want. We share this world in all kinds of ways. Try an experiment. Watch the final pictures and make up your own story of the adventures of a travelling atom. Part 6: A Little While Aware This is my house. An old fashioned house on a side street in a small city in Wisconsin. The city that the house is a part of, is itself a part of the biosphere of planet earth. A small planet that orbits a medium sized star we call the sun. One sun out of many billions of suns in the Milky Way Galaxy. Which galaxy is one galaxy out of many billions in the known universe. As to the unknown universe-that is a different story. In all that wild lost space out there may be other houses like mine and yours. Or there may not be. That we don't know. What we do know is that we know. That we are aware of that wild lost space and of this spaceship we live on. Friends, what are you doing? I know what I'm doing right now. I'm talking to you. We are both people with brains and eyes and hearts and we both play a pretty important part in this universe. We make it aware of itself. For a little while. We live on this splendid spaceship and we make it cry love. For, in a way ... We are the air, the rocks, the water. We are the earth we walk upon One way I play is by waking up in the morning, and looking out my window to see what the world is like. I'm never disappointed. It's always different. One morning it has snowed. A special snow as always. Some winters the snow never stopped piling up. But then there was always spring. That, too, was different. And the same too. Things are like that, the same, only different. But what I want to know is ... How do they do it? An Indian poet, Rabindranath Tagore, put it "That I exist is a perpetual surprise, which is life." He also said, "roots are the branches down in the earth. Branches are the roots in the air." And over a thousand years before Tagore and me and you, a poet named Praxilla knew what we are talking about. She said, "the most beautiful of things I leave is sunlight. After is the glazing stars and the moon's face., then ripe cucumbers and apples and pears." Nearer to us Huck Finn and Jim, when they were floating down the Mississippi on their raft knew what it was to be a little while aware of the wide universe and the human part. As Huck said ... "It's lovely to live on a raft. Sometimes at night we'd have the whole river to ourselves for the longest time. We had the sky up there all speckled with stars, and we used to lay on our backs and look up at them and wonder whether they was made or just happened. Jim, he allowed they was made. I allowed they just happened. I judged it would of took too long to make so many. Jim said the moon could of laid them. Well, that sounded kind of reasonable, so I didn't say nothing against it, because I've seen a frog lay most as many, so of course it could be done. We used to watch the stars that fell too and see them streak down. Jim allowed they'd got spoiled and was hove out of the nest." Are Jim and Huck much different from one of the great scientists of all time, Isaac Newton who said "I must confess to a feeling of profound humility in the presence of a universe which transcends us at almost every point. I seem to have been like a boy playing on the seashore, who has found a few bright colored shells and a few pebbles, while the great ocean of truth stretches out almost untouched and unruffled before my eager fingers." Or of the poet, William Blake, who wanted us ... To see the world in a grain of sand I guess what I'm talking about is standing and staring and fishing maybe. Fishing in the wide starry universe or in the nearest smallest stream. Paying some mind to our home. Our earth home. Spaceship earth home. Perhaps we could go away some day. And then come back. Like the space heroes in science fiction. Or be reincarnated like the Hindu people believe happens. Then we could come back a little more aware than when we left. When I return will the fish still swim |