(FORTUNE Magazine) – SOMETIMES THE U.S. underestimates its own strength. In this age of increasing global competition, American science still sets the pace. According to the National Science Foundation, Americans invest more in R&D than the Japanese, Germans, British, and French combined. And that's not counting military research. Of the estimated $108 billion the U.S. will spend this year on civilian R&D, industry will shell out roughly $74 billion to pay for everything from next year's products to pure cogitation at universities and corporate brainpower palaces like Bell Labs. As the work of the young scientists in the following pages attests, money thus invested pays spectacular dividends -- in knowledge today, and other ; forms of prosperity soon. FORTUNE chose these men and women from scores of candidates nominated by senior scientists at universities, corporations, and federal labs. All the young scientists have achieved important breakthroughs; several are likely candidates for Nobel Prizes by the year 2000. Already some of their work has found practical application. After the discovery of the electron, it took electronics nearly a century to emerge; but today, in fields from biotechnology to quantum mechanics, the time from lab bench to factory floor seems closer to nanoseconds. Gone is the standoffishness that used to isolate ''pure scientists'' from technicians; smart corporations are learning to encourage both types to speed the application of new knowledge. America continues to act as a magnet for brilliant intellects. Three of the 12 young scientists shown are natives of other lands. They come for the advanced labs and the stimulation of each other's company: The U.S. scientific and engineering community is nearly a million strong, more than twice the size of Germany's or Japan's. They come not least because America, unlike more hierarchical societies, offers an environment where scientists can make names for themselves at a tender age. R&D spending keeps rising year after year, and the competition for funds is intense among the battalions of smart baby- boomers hoping to forge the future in the crucible of their minds.

PETER G. SCHULTZ, 34 HOW TO CAPITALIZE ON BODY CHEMISTRY This Berkeley chemist has created a link between biology and commerce that may prove as important as yeast in baking. He showed that antibodies, proteins the immune system makes to flag invaders such as viruses and bacteria, can be harnessed as catalysts to help make chemicals and drugs. The computer- simulated time sequence at right illustrates a process he devised: A yellow molecule, concocted in the lab and injected into the bloodstream of a mouse, stimulates the production of antibodies -- the massive red, blue, and purple structures -- to be extracted for use as catalysts. Catalysts have long been a basic tool of the chemist. Nature's most sophisticated catalysts are enzymes, the biological substances crucial to digestion and other life processes. Industry, meanwhile, has relied mainly on catalysts that are chemically clumsier and less efficient, such as the metals used in making high-test gasoline. Five years ago Schultz conceived a way to enlist the immune systems of living creatures to generate potent catalysts. He begins by analyzing the structure of a chemical -- say, a protein that he wants to cut up. During this cleaving reaction, each molecule of the protein passes through unstable configurations, known as transition states. In a test tube, Schultz creates molecules that mimic these configurations (the yellow molecules shown). Then he injects them into mice, which produce antibodies to fend off the foreign matter. Extracted and purified, the antibodies are powerful catalysts for the cleaving process. Schultz almost set the house on fire experimenting with chemicals. He was near the top of his class at Caltech, but in his junior year he began to wonder if college was worth the trouble. After a year off, working in an Ohio aluminum foundry where temperatures hit 120 degrees, he decided to give school another try. He soon embarked on his first major project, an experiment involving enzymes. With other researchers, Schultz has already produced catalytic antibodies that can speed a millionfold the splitting of esters, basic compounds used in drugmaking. Pharmaceutical companies are racing to develop new drugs using his methods. A spectacular result that may be possible: medicine to dissolve cholesterol plaques in blood vessels. Schultz was designated America's outstanding young scientist in 1988 by the National Science Foundation and is an assistant professor at the University of California. He also works at Affymax, a privately owned Palo Alto, California, company he helped start, which is looking for ways to speed up the discovery of drugs.

RODNEY A.BROOKS, 35 HORDES OF TINY ROBOTS If modern electronics is so advanced, why have the robotic butlers and cooks that have been predicted for decades failed to materialize? Brooks, an Australian-born associate professor of computer science at MIT, thinks robotics engineers have been on the wrong track. They've been trying to build machines in the human image: robots with a computer for a brain, an electronic vision system for eyes, and arms and legs all centrally coordinated. Such machines have proved too costly and slow-witted to be applied beyond simple, repetitive tasks such as welding cars. Brooks created a huge stir in the robotics world by taking as his model not humans but the humble insect. Insects rely on their brains far less than higher species; they jump, crawl, and respond to environmental stimuli by using other parts of their nervous systems that work almost autonomously. The nerves typically run along the underside of the creature's body; to complement them, nature equips insects with widely distributed sensors, including ''ears'' in such bizarre places as the abdomen, as in grasshoppers and moths, and on the front legs, as in crickets. With help from students, Brooks has imitated this distributed intelligence in some of the smallest robots built. The six-legged, foot-long robot shown is named Genghis. In an MIT lab it creeps toward a human visitor after spotting him with infrared eyes. It detects obstacles in its path with antennalike whiskers, and clambers over them by ''feeling'' them with sensors in its legs. Brooks envisions building hordes of tiny, low-cost robots to tackle specialized tasks, such as scouring barnacles off the hulls of ships or fanning out across the plains of Mars as scientific scouts. Minute robots might be injected into the bloodstream to perform surgery from within. A wacky dream? Ross Perot, for one, doesn't think so. He set up Gnat Robot Corp. to help Brooks's wee automatons establish a beachhead in the market.

SHARON R. LONG, 39 WHY PLANTS TALK With each generation, more and more talented women move into the sciences; FORTUNE has chosen three for these pages. Sharon Long has shown an uncanny ability to use the tools of one discipline to solve mysteries in another. Like several of FORTUNE's top scientists, she switched fields early in her career, moving into molecular genetics after mastering chemistry and developmental biology at Caltech, Yale, and Harvard. Today she is an associate professor of biology at Stanford. Each year the world's farmers spread nearly 80 million tons of nitrogen fertilizer on their crops to jump-start growth. Long's research may make it possible to start weaning agriculture off the fertilizer habit by equipping major food crops with microscopic fertilizer factories. A few crops, such as soybeans and alfalfa, already make their own fertilizer by working symbiotically with a bacterium called rhizobium. The bacteria reside in nodules in the plants' roots. (The mass in the photo is a nodule; individual cells show up green and bacteria, orange.) The bacteria extract nitrogen from the air -- something the plant can't do -- and supply it to the plant as ammonia, the version of nitrogen plants use for growth. In exchange, the plants provide the bacteria a place to stay and nourish them with sugars - produced through photosynthesis. The process by which the plant locates rhizobium bacteria in the soil and forms nodules they can inhabit involves chemical communication between bacterium and plant. Charting the details of that conversation could be the first step in getting crops such as corn, wheat, and rice to develop the ability to nourish themselves. Using imaginative combinations of molecular biology and electrophysiology, Long is decoding the rhizobium-alfalfa conversation. Four years ago she and her colleagues found the signal from the plant that starts the dialogue. It turned out to be a molecule of flavonoid -- a bright yellow substance that ancient Romans used as a dye. The message it sends to the bacteria, in essence: ''Rhizobium, come to work!'' In response, Long recently proved, rhizobium near the alfalfa roots emit a chemical signal of their own. They tell the plant: ''We got your message and we're on our way. Start preparing nodules.'' Says Long: ''I like to think of it as a dialogue in a play. We've got the scenery. We've got the first sentence. We've got the second sentence. Now we want to know the reply. We'll see if the third sentence leads to a lot of furniture rearrangement.'' Eventually, genes that enable plants to hold such dialogues could be inserted into crops that don't make nodules for rhizobium now. That, in turn, could change the face of agriculture.

MICHAEL H. FREEDMAN, 38 MASTER OF DIMENSIONS This math wizard hated numbers in high school. ''I resented them as being artificial and getting in the way,'' Freedman says. His great gift, the ability to think geometrically rather than numerically, led to a historic breakthrough in topology that won him the National Medal of Science and a five-year ''genius grant'' from the MacArthur Foundation. Topology is sometimes called ''rubber sheet geometry.'' It is the branch of pure mathematics that deals with the qualities of objects rather than their sizes and shapes: Topologists study features that can't be lost if an object is stretched, twisted, or otherwise deformed. In this way of looking at the world, a doughnut and a coffee cup are the same because each has only one hole. A goal of topology is to classify multidimensional surfaces, which practitioners call manifolds. Everyday forms, such as spheres, can exist in any number of dimensions: To imagine what is meant by an eight-dimensional sphere, think of a golf ball, and add to its usual three dimensions measures for its age, color, temperature, weight, and bounciness. (At left is a computer rendition of a doughnut in 4-D space.) A century ago the great French mathematician Henri Poincare devised a clever way to classify manifolds. He would imagine a loop of string on the surface and determine how far the loop could be shrunk. On a sphere, for instance, any loop can shrink to a point; but on a doughnutlike torus, a loop that encircles the hole can't shrink smaller than the hole's circumference. Hence, the sphere and the torus are said to belong to different groups. Three-dimensional manifolds are a special headache for topologists. They can be stretched and folded so many ways that no one has been able to classify them. In 1904, Poincare outlined a set of simple tests and challenged colleagues to prove that any 3-D manifold, no matter how distorted, is a sphere if it satisfies the tests. This challenge is called the Poincare conjecture; paradoxically, mathematicians were able to prove it only for spheres of five dimensions or more. Freedman was the first to create a proof for four-dimensional spheres. Part of his reasoning: One should be able to shrink to a point not only loops but also two-dimensional spheres embedded in the 4-D manifold. The work consumed seven years; while his discovery has no concrete application as yet, Freedman, a professor at the University of California at San Diego, says: ''All mathematics has practical potential.'' Example: knot theory, a branch of topology devoted to classifying knots. Long thought arcane, it is now hugely important to biochemists. They use it to explain how strands of DNA that lie jumbled like garden hose in the nuclei of living cells can divide without getting hopelessly snarled.

SUSAN SOLOMON, 34, SOLVING THE RIDDLE OF THE OZONE HOLE As a 10-year-old growing up in a middle-class Chicago neighborhood, Solomon remembers being entranced by Jacques Cousteau's televised adventures: ''I decided right then that science was the most wonderful thing you could do in the world.'' Now her work in chemistry is bringing her to the question of life's survival on earth. In 1985, Solomon was a researcher at the National Oceanic and Atmospheric Administration in Boulder, Colorado, when scientists detected an ozone hole over the South Pole. This is a gap in the atmosphere's ozone layer, located between the altitudes of 32,000 and 74,000 feet, which normally shields the earth from the sun's ultraviolet radiation. Even in moderate doses, such radiation can cause skin cancer; unblocked by the atmosphere, it would wipe out life on earth. ''The discovery was a tremendous shock,'' Solomon remembers. ''We had been predicting a 5% to 10% ozone depletion in 50 to 100 years. All of a sudden we were observing a 50% depletion.'' (In the satellite image of Antarctica above, the ozone hole is the gray and dark-blue region near the crosshairs.) Scientists suspected the damage was caused by chlorofluorocarbons, man-made gases widely used in refrigerators, aerosol cans, and the making of semiconductors. But the process by which so much ozone disappeared was a mystery. Like many chemists around the world, Solomon spent months on the problem. The critical insight hit her at a lecture in San Francisco on polar stratospheric clouds. Until then, these airborne formations of ice crystals were little more than a scientific curiosity whose iridescent beauty gave them the nickname mother-of-pearl clouds. But as the lecturer flashed slides of the cloud layer, recalls Solomon, ''I suddenly started thinking, 'Those clouds are much more extensive in Antarctica than anywhere else; what if ozone depletion takes place when CFC derivatives react on the cloud surfaces?' '' She organized an expedition to Antarctica to gather data; the trip and other experiments brought confirmation for her theory within a year. Industrialized nations soon began regulating CFC use, and last year Solomon received the Department of Commerce's gold medal for ''impeccable science in the cause of humankind.'' Lately she has shifted her attention to the Arctic, where ozone depletion may threaten the Northern Hemisphere. Although the ozone layer is constantly replenished in the atmosphere, this happens at a rate far too slow to compensate for the damage done by humans. The only solution, Solomon believes, is virtual prohibition of the offending chemicals, and she praises recent efforts by chemical manufacturers to develop CFC substitutes.

BONNIE ANN WALLACE, 39 THE GATES OF THE CELL Killer maladies such as cystic fibrosis, cancer, and heart disease are thought to disrupt the pumping of nutrients and other substances through the walls of the body's cells. The apparently simple question of how this flow works baffled researchers for generations. In 1988, Wallace found the solution by analyzing in exquisite detail the structure of a molecule that works as a supply channel in a cell wall. She mapped each of its 520 atoms and 602 atomic bonds, and also discovered that the molecule opens and closes a passage through its center by changing shape. (Two such molecules appear behind Wallace in the computer-generated image at left.) Wallace likens the molecule to a Chinese finger puzzle. When it is letting in nourishment, it becomes short and squat, allowing electrically charged particles known as ions to pass through the hole in its center. At other times it becomes long and thin so the hole is too narrow for ions to pass. Even as a small girl in Greenwich, Connecticut, Wallace always wanted to know how things worked. She was so impressive as a high school chemist that a teacher allowed her to do experiments her own way. She graduated from Rensselaer Polytechnic Institute in Troy, New York, earned a Ph.D. at Yale, and eventually returned to Rensselaer as a professor. For her study of ion channels she chose gramicidin, an early antibiotic that has fallen into relative disuse because it produces serious side effects when taken internally. Applying a battery of techniques from X-ray diffraction to infrared spectroscopy, Wallace and her colleagues traced cesium ions passing through molecules of the drug. An immediate benefit of Wallace's research may be to rehabilitate gramicidin as an antibiotic for general use. The drug works by puncturing holes in bacteria, allowing ions to escape so the bacteria deflate like balloons; its side effects derive, apparently, from an unfortunate tendency to wreak similar havoc on human cells. Wallace and her associates are trying to make the drug more selective in what it kills. Hundreds of other channel molecules beckon to be investigated. Cystic fibrosis, a congenital disease that afflicts 17,000 Americans, recently has been found to result from a poorly regulated flow of chloride ions into the cells of the lungs. Understanding how the disease sabotages channel molecules may eventually lead researchers to a cure.

PAUL A. BOTTOMLEY, 37 A NEW WINDOW INTO THE BODY One afternoon in 1977, after months of preparation, Bottomley stuck his arm into an experimental nuclear magnetic resonance machine. The technology had been developed for chemical analysis, but the young physicist and his co- workers believed it could be used as a window into the human body. He proved that by producing a vivid cross section of his left wrist on the display of a computer hooked to the machine. + A native of Melbourne, Australia, who started out in chemistry and switched to physics, Bottomley did the experiment at England's Nottingham University. The following year he moved to the U.S. in search of a broader scientific community, better equipment, and a higher salary. After two years at Johns Hopkins University in Baltimore, he joined General Electric's research and development center in Schenectady, New York. By 1982 he and his colleagues had built a magnetic resonance machine powerful enough to produce high-resolution images of the human head. When the machine was switched on, it made images so much better than expected that the ordinarily laconic Bottomley couldn't contain his enthusiasm. He recalls: ''I got so excited that I grabbed a cleaning man by the shoulders in the hallway and dragged him in to look.'' Today massive machines for magnetic resonance imaging, or MRI, let doctors see into the body and diagnose disease without surgery, X-rays, or the injection of radioactive dye. (Shown in the photo: a cross section of the human chest.) Meanwhile, Bottomley has pioneered what is known as magnetic resonance spectroscopy. His goal is to reveal the body's living chemistry, extending MRI technique to record not only physical features within the body but also biochemical changes that accompany -- and sometimes precede -- the symptoms of disease. In 1985, Bottomley led a team that produced the first such analysis of the beating heart. The procedure revealed both the organ itself and details of its chemistry by tracing the distribution of chemical by-products of the heart's exertions. Such information may allow cardiologists to spot regions of the heart damaged by a heart attack and to monitor the effect of heart medications on the organ's metabolism -- action that can't easily be observed with other diagnostic techniques. Using the same method, oncologists may be able to monitor tumors to gauge the effectiveness of cancer drugs. Both imaging and spectroscopy are accomplished with the same MRI machine, which surrounds the patient with huge magnets. So powerful is the magnetic field that the nuclei of atoms in the patient's body line up parallel to it. A coil in the machine then jolts the nuclei with high-frequency radio waves, causing them to resonate like infinitesimal tuning forks. They produce a faint radio signal that is amplified, recorded, and translated into an image or a diagnostic chart. Medical spectroscopy is just beginning to find its way into ( clinical experiments, but when it is perfected and its findings better understood, it could usher in an age of nearly instantaneous diagnosis.

DONALD M. EIGLER, 37 THE MAN WHO MOVES ATOMS Around 400 B.C. the Greek philosopher Democritus postulated the existence of an ultimate ''uncuttable'' particle of matter he named the atom. It has taken 24 centuries for humans to actually seize one and move it. Physicist Eigler did, at IBM's Almaden Research Center in San Jose, California, last November. Not only has he succeeded at moving individual atoms but he has also begun to assemble them in primitive structures, such as the row shown. Eigler used a Nobel Prize-winning IBM invention, the scanning tunneling electron microscope. That remarkable instrument, perfected in the early 1980s, made atoms on surfaces clearly visible for the first time. It works by positioning a fine metal probe next to the material under observation. A weak voltage applied between the tip and the material causes electrons to flow between the two; tunneling refers to the quantum mechanical process by which the electrons cross the gap. As the tip is moved along the surface, it reveals the contours of the atoms below. Scientists suspected that the microscope could be used to rearrange atoms. In 1987 a team at AT&T's Bell Laboratories reported having moved a germanium atom inadvertently picked up by the microscope tip. But they were unable to control the phenomenon, in part because atoms at room temperature are too energetic for the microscope to grab -- they literally jump away. Eigler, meanwhile, modified a microscope to operate in a vacuum at temperatures near absolute zero, conditions under which atoms are tamer. The project took five years; he says his knack for building things derives from childhood training by his father, an aerospace engineer. The experiment involved a platinum sheet that had been exposed to the heavy gas xenon. The microscope revealed xenon atoms scattered on the platinum like soccer balls on a frozen playing field. Eigler found that he could reposition the atoms, one by one, by moving the microscope tip close and dragging them along. His first application of the technique was pure showmanship: He arranged 35 atoms to spell out the IBM logo in letters one-500,000th the size of those on this page. Next he created the first man-made atomic cluster, seven xenon atoms bound in a row by shared electrons (see photo). Ultimately, atoms may serve as building blocks for ultrasmall electronic circuits; Eigler is inching toward such a feat by teaching himself to assemble simple molecules, such as those of carbon dioxide, an atom at a time.

BJARNE STROUSTRUP, 39 MAKING COMPUTERS WORK THE WAY PEOPLE DO Growing up in a working-class family in Aarhus, Denmark, Stroustrup was more interested in soccer than schoolwork until a gifted teacher guided him into math. Computers became his passion in college. While he was earning a Ph.D. at Cambridge, his work on software for computer networks caught the eye of recruiters from Bell Labs. In 1979 they asked him to join their famous institution, explaining, in typical Bell Labs fashion, that his salary would be paid for a year and then he would be asked what area he'd like to pursue. A few years later Stroustrup startled the technical world with a programming language, C++, that is fast becoming computing's lingua franca. It is part of a software revolution, known as object-oriented programming, that is going on unbeknownst to ordinary users. Traditionally, programmers took pride in their ability to distill the world's complexities into linear, step-by-step instructions that computers can follow with their blindingly fast but simple brains. That approach has led to soaring costs and long delays in the creation of large programs, such as those that control the switching of phone calls. Object-oriented programming, in contrast, vastly simplifies human interaction with the machine by making computers work more the way people think. It gives the programmer sets of tools that he or she can readily manipulate. Say a programmer wants to create a new type of ''window'' for framing data on the screen. Doing so in a traditional language would mean writing complex and lengthy commands. In C++ a simple command, OPEN A WINDOW, causes the machine to call up other windows that have been defined previously; the new window automatically inherits their attributes, and the programmer customizes it by varying a few. The details remain hidden from the programmer's view, much as the intricacies of weaving and dyeing cloth are hidden from a tailor. Says Stroustrup: ''What I deal in is control of complexity.'' Little wonder that the use of C++ is doubling every eight months. It has been used to program a wide range of machines, from supercomputers to lowly PCs (a retail version of C++ costs less than $100). It helped make possible the versatile graphics of Apple's Macintosh line and has worked its way into products from Hewlett-Packard and Sun Microsystems. What delights Stroustrup most is the rapid spread of C++ in developing countries. He gets fan mail from Hunan and inquiries from South America, and his book on C++ is being translated into Serbo-Croatian. A key to its appeal, he explains, is that C++ runs much more efficiently than other sophisticated languages on ordinary personal computers: ''It's in essence low tech. You no longer need a superduper workstation to do superduper work.''

MARK A. REED, 35 CAGING AN ELECTRON With astonishing speed, humans are gaining mastery over the tiniest manifestations of matter. Physicist Reed has succeeded in trapping individual electrons and controlling their actions. His goal: to build computer memory and logic cells so tiny that more than a billion would fit in a period on this page. Three years ago, at Texas Instruments' central research laboratories in Dallas, he constructed the first so-called quantum dot, a box only ten times the diameter of an atom on a side. Beginning with a sandwichlike wafer of gallium arsenide and related materials, he used sophisticated chip-etching techniques to carve the thicker towerlike structures shown in the electron micrograph above. Each tower embodies a quantum dot. By applying a small voltage to the tower, Reed is able to imprison a single electron within it. At that infinitesimal scale, quantum effects reign. Acting less like a particle than like a wave, the electron keeps sloshing inside its quantum cage. Reed can also control the sides of the dot. By applying an electrical potential to one of the walls, he can make it ''transparent'' to the captured electron so that the electron can exit, or tunnel, into an adjoining quantum dot or be sent elsewhere via a gallium-arsenide structure called a quantum wire. The quantum dot can serve as the smallest memory cell ever devised: An electron's presence can stand for a binary 1 or YES; its absence can represent 0 or NO. Many scientists think chips incorporating the dots will make possible the next major leap in electronics. Conventional semiconductor chips, which work by channeling whole flows of electrons, are expected to reach the limits of miniaturization by the end of the decade. A shift to quantum chips could make possible a plethora of exotic devices -- from hand-held supercomputers to capacious memory units the size of a walnut. But while other companies and some universities already have built rudimentary quantum transistors, no one knows whether quantum chips can be economically mass-produced. For the time being, says Reed, now a professor at Yale, ''these structures are miniature laboratories for doing quantum mechanics -- they're just tremendous fun.''

MARC R. MONTMINY, 34 A CHEMICAL KEY TO MENTAL DISORDERS The brain is an electrochemical caldron where billions of neurons fire tiny electrical pulses. The chemicals that carry and modulate those pulses govern our health, our emotions, and our thoughts in ways science is only beginning to understand. In his lab at the Salk Institute in LaJolla, California, Montminy has analyzed the production of a key brain chemical, somatostatin. Too much somatostatin has been linked to dwarfism and anorexia nervosa, the compulsive refusal to eat; too little is associated with clinical depression and the devastating symptoms of Alzheimer's disease. By studying genes within brain cells, Montminy showed how stimuli -- such as the everyday act of drinking coffee -- can help activate a DNA segment that in turn initiates somatostatin production. The gene is turned on and off by a kind of molecular switch -- a molecule that straddles the DNA and blocks it from working, somewhat like the Denver boot police use to immobilize a scofflaw's car. Montminy has analyzed the switch (a map of the molecule appears behind him) and shown how it can be locked and unlocked chemically, knowledge that may speed the search for an Alzheimer's cure. Montminy's work could lead to other new medicines, even for the common cold. Switches like those he discovered occur in cold and other types of viruses. By developing drugs that replace those switches with defective ones -- locks that won't open -- science may be able to prevent cold viruses from reproducing. Growing up in Lewiston, Maine, Montminy wanted to be a doctor. He remembers borrowing a blood pressure cuff from his mother, a nurse, at age 8 and taking it to school to show his classmates. He studied medicine at Tufts but later switched to neurochemistry in the belief that he could help more people by doing research. That may prove spectacularly right.

ALAN DRESSLER, 42. ON THE TRAIL OF THE GREAT ATTRACTOR He became hooked on astronomy as a 5-year-old boy, the moment he saw the majestic rings of Saturn through a telescope in Cincinnati's Hyde Park. Now a staff astronomer at the Carnegie Observatories in Pasadena, California, Dressler is shaking up conventional astronomical wisdom. In the nearby Andromeda galaxy, he helped locate a black hole, a celestial abyss that sucks in light and matter like a cosmic vacuum cleaner. Then, in 1986, he and his team discovered an object that is like something straight out of science fiction. The Great Attractor is a mass of dark matter, unimaginably large, 200 million light-years from Earth. The Attractor is invisible -- it makes its presence known only through its immense gravitational tug on galaxies. Our home galaxy, the Milky Way, is one of thousands in its grip. This finding raises important questions about the Big Bang, the huge explosion believed to have started the universe. Cosmologists, who study its origin, have long assumed that the Big Bang spread matter smoothly across the heavens. Now Dressler has demonstrated the universe to be lumpy, like oatmeal. ''There must be an element of the Big Bang we don't understand,'' he says. ''It seems unlikely that the universe could have gone from smooth to its current state. For something as vast as the Great Attractor to have formed, either the primordial cosmos had larger structures than we previously thought, or the universe has taken longer to evolve.'' Dressler's discovery was based on years of work, with colleague Sandra Faber, at Carnegie's Las Campanas Observatory high in the Andes Mountains of Chile. The air at that remote site is so clear, says Dressler, that one can read a newspaper by the light of the Milky Way. Clearly visible overhead are the galaxy's millions of stars, deep dark rifts, and objects such as the Eta Carina nebula (see photo). Dressler says the sight can transfix an observer: ''It becomes an emotional experience.'' What moves him most profoundly, however, is not the spectacle of the heavens but the human mind: ''Most people are awed by the size of the universe and our being so small. My view is completely opposite. The mind is the most complex thing we know of -- complexity resides not out there but here, in our biology and our minds. The marvelous thing is that we can discover, understand, and contemplate the universe.''