Scientific American Presents Article Index

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Building the Elite Athlete
Introduction: Game Theory Science increasingly informs athletic training
How Much Higher? How Much Faster? Limits to human performance are not yet in sight
A Matter of Size Professional players keep getting bigger, and records continue to topple
The Chemical Games Biotechnical advances and administrative loopholes enable devious athletes to take performance-enhancing drugs without much risk of being caught or sanctioned
Toward Molecular Talent Scouting Scientists are engaged in a frustrating search for genes to identify future Olympians
The Female Hurt Women are more vulnerable than men to certain injuries and may not be getting proper treatment for them
Psyched Up, Psyched Out Some athletes swear by it. Others laugh at it. Can science determine if sports psychology works?
Blowing the Whistle on Concussions Raps to the head can debilitate or even kill athletes. Yet concussions are often misdiagnosed and mistreated
Watching Your Steps A new appreciation of the diversity of running styles may eventually yeild shoes custome-fit to their wearers
No Way Up Practitioners of the world?s most technologically sophisticated extreme sport, cave divers risk death on each journey through a maze of watery passageways
Going through the Motions The field of biomechanics demonstrates how the scientific study of sport and the training of athletes are often at odds
Asphalt Acrobats To pull off spectacular tricks, crafty skateboarders bend the laws of physics
The Athletic Arms Race Does better equipment heighten competition or ruin the game
The Unblinking Eye Technologies that can see better than humans encounter a mixed reception on the playing field
Out of This World Forget Sydney. The wildest Olympic sports could be played on the moon, Mars or the asteroid nearest you
Deconstructing the Taboo The intertwining of genetic, environmental and cultural influences makes it impossible to fathom why blacks dominate certain sports
Unlikely Domin-ation Dominican baseball players. Chinese Ping-Pongers. Why do certain countries, even poor, tiny ones, dominate certain sports?
A Sphere and Present Danger Investigating the possibility that bat days are an excuse to whack that loudmouth in the next row
The Quest to Beat Aging
Introduction: When Life Knows No Bounds Postponing death changes the meaning of life
Getting Ever Older/How Long Have You Got? The first 150-year-old person might be alive right now
Getting Ever Older/Design for Living What centenarians can teach us about how to grow old
Getting Ever Older/From Baby Boom to Geezer Glut By 2030, one in five Americans will be a senior citizen
Getting Ever Older/Social Insecurity You'd better save like crazy if you want to fund a 30-year retirement
The Battle Against Aging/Living Longer: What Really Works? The elixirs du jour - antioxidants, gene therapy and aerobic conditioning - have yet to prove that they do much better than the potions and patent medicines of yesteryear
The Battle Against Aging/Radical Proposal There may be a way to prevent ourselves from rusting from the inside
The Battle Against Aging/The Famine of Youth Severely restricting diet may increase life span, but few will be able to follow such a harsh regimen
The Battle Against Aging/Counting the Lives of a Cell Studies of clocklike elements in the nucleus of cells could lead to a range of therapies that might bolster the immune system, reverse heart disease, even combat cancer
The Battle Against Aging/Mother Nature's Menders Stem cells might routinely repair our worn-out tissue, if society accepts this approach
The Battle Against Aging/Spare Parts for Vital Organs Engineers are creating artificial replacements for failing hearts, kidneys, pancreases and livers
The Battle Against Aging/Of Hyperaging and Methuselah Genes Children with diseases of the elderly and studies of genes that extend life span in animals are opening a window on how we age
Thwarting Major Killers/Preventing Good Brains from Going Bad The fight against two life-robbing diseases, Alzheimer's and Parkinson's, has just begun
Thwarting Major Killers/Stopping Cancer Before it Starts Early intervention may prevent cancer from becoming inevitable with age
Thwarting Major Killers/Saving Hearts That Grow Old Better understanding of atherosclerosis - the inflammation and buildup of fatty deposits in blood vessels - has triggered new approaches to treating the nation's leading cause of death
Meditations on Quality of Life/Promised Land or Purgatory Whether old age is worth living depends largely on mental health
Meditations on Quality of Life/Cults of the Undying The prospect of living forever, or at least a millennium, has served as a theme for storytellers throughout history
Introduction/Our National Passion Preoccupation with weather reflects both our hunger for constant change and our need to recover a lost sense of awe toward the natural world
The Perils of Prediction/Forecasting is No Picnic By the time you hear the five-day forecast on the evening news, meteorologists have already been making and revising those predictions for a week or more
The Perils of Prediction/Decoding the Forecast A glossary of common weather terms
The Perils of Prediction/The Butterfly that Roared To improve weather forecasting, meteorologists have learned to pay attention to the effects of chaotic airflows in the atmosphere
The Perils of Prediction/Do We Need the National Weather Service? Private forecasters are taking over more and more of the responsibilities that were traditionally fulfilled by government meteorologists
Unsettled Skies/Billion-Dollar Twister Oklahoma, America's most frequent victim of tornadoes, suffered more twister-related destruction on May 3, 1999, than ever before. What are we learning from this epic event - and could it happen somewhere else?
Unsettled Skies/Extreme Weather A tour of the most dramatic weather on the planet
Unsettled Skies/Fleeing Floyd Thousands who tried to race to safety before Hurricane Floyd hit last year ended up going nowhere fast, stuck in traffic. Were such problems a fluke or a glimpse of the future?
Unsettled Skies/Big Sky, Hot Nights, Red Sprites A maverick meteorologist's backyard has become a mecca for devotees of a new kind of lightning
Unsettled Skies/It's Raining Eels: A Compendium of Weird Weather A Compendium of Weird Weather
Unsettled Skies/Tempests From the Sun A gale of particles rushing from the sun streams continuously around Earth. Solar storms can release gusts that spell trouble for satellites and for electrical systems on the ground
Doing Something About It/Cloud Dancers Will efforts to change the weather ever attain scientific legitimacy?
Doing Something About It/Weatherproofing Air Travel Nervous fliers can take solace from new technologies that alert pilots to imminent hazards, from turbulence to wing icing
Climate in Flux/Beyond El Niño El Niño is not the only oceanic and atmospheric event that profoundly affects climate. Several other seesawing conditions have also been uncovered
Climate in Flux/Warming to Climate Change Global warming is upon us, scientists say - and some communities are ready to react. Together researchers and local leaders are planning for hot, wet - or just plain bizarre - weather to come
Climate in Flux/Under the Weather Weather and climate can affect health in ways that are far from obvious
Atmosphere As Spectacle/Channeling the Weather Being a weatherman ain't easy
Atmosphere as Spectacle/Lights, Camera, Weather Movies may show people singing in the rain or charging after twisters, but the weather you see is rarely authentic
Your Bionic Future
Introduction: Your Bionic Future As life and technology merge, they will both become more interesting
Your New Body/Couture Cures: This Drug's For You Doctors may one day sneak a peek at your genes to determine which drugs will cure you and which might kill you.
Your New Body/Growing New Organs Researchers have taken the first steps toward creating semisynthetic, living organs that can be used as human replacement parts
Your New Body/Embryonic Stem Cells For Medicine Cells able to generate virtually all other cell types have recently been isolated. One day they could help repair a wide variety of damaged tissues.
Your New Body/Head Transplants Equipping old minds with new bodies - whether you call it head transplantation or body transplantation - is not outside science?s ken. How would it work?
Your New Body/Muscular Again Within a decade or two, scientists will create a genetic vaccine that increases muscle mass - without exercise.
Your New Body/Making Methuselah Immortality may not be in the cards, but worms, flies and pigeons may be able to teach us a thing or two about living better longer.
Your New Senses/Are Your Ready For a New Sensation? As biology meets engineering, scientists are designing the sensory experiences of a new tomorrow.
Your New Senses/Feeling the Future Our sense of touch will not be replaceable, it will be enhanceable.
Your New Senses/Getting Real In Cyberspace Virtual reality is not in suspended animation. Lately researchers have made impressive advances in conveying the senses of smell and touch.
Your New Senses/Nosing Out a Mate All other mammals rely on chemical attractants to find that special someone. Will human suitors of the future be able to pack the power of pheromomes?
Your New Mind/The Coming Merging of Mind and Machine The accelerating pace of technological progress means that our intelligent creations will soon eclipse us - and that their creations will eventually eclipse them.
Your New Mind/Tweaking the Genetics of Behavior How might new advances in behavioral genetics affect you and your children? A fictional couple plays design-a-baby
Your New Look/When Off-The-Rack Becomes Off-The-Net Virtual-reality technology, the Internet and computer-aided manufacturing may soon combine to bring custom clothing to your closet.
Your New Look/Smart Stuff The jewelry box of the future could include rings that remember your predilection for vanilla-flavored café au lait.
Your New Look/What The Well-Dressed Warrior Will Wear Power-generating, chameleonic clothes, food made from bugs and leaves, and tiny robotic scouts may assist the soldier of the next century.
Your New Society/Will We Be One Nation, Indivisible? Racial tensions will ease and disparities will narrow, but experts disagree on whether racism will disappear even in 100 years.
Your New Society/I, Clone Sometime, somewhere, someone will generate a cloned human being. What will happen then
Your New Lifestyle/Living in Technology Powerful microprocessors and the Internet may finally deliver whole-house control. But are you ready for the "therapists of the new millennium"?
Your New Lifestyle/Future Feast Even the meat and potatoes are being reinvented: the meat could come from a test tube, and the potatoes could ward off cholera.
Your New Lifestyle/The New Metropolis Can "new urbanism" be applied to urban America?
Your New Lifestyle/The Ultimate Baby Bottle Are artificial wombs our future? Was Aldous Huxley right?
Men: The Scientific Truth
Measures of Man Hormones and bluster produce the hero, the cad and the shorter-lived of the sexes. Insights into both male psychology and biology may temper untoward behavior and enhance longevity
Darwinism and the Roots of Machismo Men's evolutionary heritage probably has made them risk takers. But some of the harmful consequences can be moderated
Men, Honor and Murder Maleness and aggression do not have to go together. A "culture of honor" underlies some high murder rates
The Key to Masculinity The Y chromosome causes an embryo to become male by directing the development of the testes. But new research indicates that the Y does much more
Sex Differences in the Brain Men and women display patterns of behavioral and cognitive differences that reflect varying hormonal influences on brain development
Lessons Learned from Living Life history studies begun more than 60 years ago have started to reveal the components of successful maturation and aging
Balancing Work and Family Fathers who live with their families are spending more time with their children. At the same time, more fathers are not living with their families
Can Work Kill? Recent studies suggest that stress on the job can be deadly
The Most Dangerous Occupations Aircraft pilots, truckers and construction laborers make the top 10. Women would prefer to work at Microsoft
The Mystery of Muscle Lately researchers have made some intriguing discoveries in their attempt to unravel one of the long-standing puzzles of human physiology - how exercise builds muscle
Extreme Sports, Sensation Seeking and the Brain "Type T" personalities push themselves to the brink of death for the neuronal rush or to relieve the ennui of modern life
Spokes Man for a Hard Problem The scientific evidence suggests that too much time in a bike saddle may leave your sex life in ruins
Impotence in the Age of Viagra A new understanding of the mechanism that causes erections has led to a wide range of options for treating impotence
The Circumcision Dilemma Physicians in the U.S. are at odds over neonatal circumcision. Is it preventive medicine, cosmetic surgery or inhumane mutilation?
Of Babies and the Barren Man Male infertility can now be treated with advanced surgical and reproductive techniques. Most infertile men can become fathers
Beyond the Condom: The Future of Male Contraception The physiology of sperm production complicates development of new forms of men's birth control, but contraceptive researchers continue to explore new leads
Teenage American Males: Growing Up with Risks Compared with adolescent girls, boys face more danger from alcohol and drugs, auto accidents, HIV, homicide and suicide
Grappling with ADHD Ritalin seems to help affected children in more ways than one, but doubts still persist about long-term effects
Treating Men Who Batter Women Treatment programs for men who abuse their partners are proliferating, but their effectiveness remains unclear. A growing body of research about the types of men who batter may help experts tailor treatment more precisely
Combating Prostate Cancer Recent advances in diagnosis and treatment promise to extend survival time and improve the quality of life for many patients
Longevity: The Ultimate Gender Gap An American man's average life span is nearly six years shorter than a woman's. Differing hormone levels and lifestyle choices may help explain the disparity
The Future of Space Exploration
The Flagships of the Space Fleet By exploring planets, moons, asteroids and comets, these spacecraft are extending the frontiers of human knowledge
Key Space Explorations of the Next Decade Key Space Explorations of the Next Decade
The International Space Station: A Work in Progress The U.S. and its international partners are finally building a space station, even as they continue to argue about the blueprints
Robots vs Humans - Who Should Explore Space? Unmanned spacecraft are exploring the solar system more cheaply and effectively than astronauts are - Astronaut explorers can perform science in space that robots cannot
The Mars Pathfinder Mission The first rover to explore Mars found in situ evidence that the Red Planet may once have been hospitable to life
What's Next for Mars In the coming decade the planet named for the god of war will be the target of a scientific armada from Earth. Researchers hope to settle many questions about Mars, including whether life ever flourished there
Sending Humans to Mars A leading advocate of manned misions to Mars outlines a plan t land astronauts on the Red Planet in the next decade.
Bringing Life to Mars Climate models suggest that human beings could transform the Red Planet into a more Earth-like world using current technologies
The Way to Go in Space To go farther into space, humans will first have to figure out how to get there cheaply and more efficiently. Ideas are not in short supply
Air-Breathing Engines For years, engineers have dreamed of building an aircraft that could reach hypersonic speeds, greater than Mach 5, or five times the speed of sound.
Space Tethers When humans begin to inhabit the moon and planets other than Earth, they may not use the modern technology of rockets.
Highways of Light Today's spacecraft carry their source of power.
Light Sails Science-fiction dreams of worlds beyond our own solar system have taken on a more realistic aspect since astromomers discovered that the universe contains planets in unexpectedly large numbers.
Compact Nuclear Rockets Someday, in exploring the outer planets of our solar system, humankind will want to do more than send diminutive probes that merely fly rapidly by them.
Reaching for the Stars The notion of traveling to the stars is a concept compelling enough to recur in counteless cultural artifacts, from Roman poetry to 20th-century popular music.
The Best Targets for Future Exploration So much to see, so little money.
Interstellar Spaceflight: Can We Travel to Other Stars? Small self-replicating probes could be launched on interstellar journeys. Creating a galactic Internet may yield even greater benefits
Making Money in Space Exploring the solar system turns out to be the easy part. The next great challenge will be creating profitable space enterprises.
New Satellites for Personal Communications Fleets of satellites will soon make it possible to reach someone anywhere on Earth, using nothing more than a small handset
Tapping the Waters of Space Space travel could be considerably cheaper if astronauts could produce their own food and propellants from the resources already out there
Exploring Space on the Internet Thanks to the World Wide Web, anyone with an Internet connection can explore space vicariously, browsing through dozens of Web sites for the latest news about space missions and projects.
Extreme Engineering
Engineering at the Edge of the Possible For millennia, engineers have pushed the limits of human ingenuity. Here are some of their all-time greatest achievements.
The Big, The Small/Mighty Monolith The largest dam in history is being constructed at China's Three Gorges. The controversial $27-billion project won't be completed until 2009
The Big, The Small/Some Assembly Required Scientists can now grab an individual atom and place it exactly where they want. Welcome to the new and exciting world of atomic engineering
The Big, The Small/Building Gargantuan Software Everything about Windows 2000 is huge, starting with its 29 million lines of code. To tame this monster, Microsoft had to develop a new set of strategies, all while getting more than 4,000 computer geeks to work as a team
The Big, The Small/Life in Space The International Space Station, the only extraterrestrial construction project, will be ready for inhabitants by March 2000
The Big, The Small/A Small World Miniature diagnostic labs, PCR-on-a-chip, handheld biotoxin sensors and other reports from the world of microscopic biological and medical devices
The Big, The Small/Bringing Back the Barrier Louisiana is working to protect its rapidly disappearing wetlands, including restoring an entire island
The Powerful, The Strong, The Fast/Seven Wonders of Modern Astronomy The most amazing telescopes and how they work
The Powerful, The Strong, The Fast/A Bridge to a Composite Future Can a bridge made of glass and carbon support four lanes of traffic?
The Powerful, The Strong, The Fast/Subterranean Speed Record The massive installment currently under construction near Geneva will be the fastest particle accelerator ever built. When it opens in 2005, it will also be the largest science experiment in the world
The Powerful, The Strong, The Fast /Blitzing Bits Supercomputers aim for petaflops - a quadrillion floating-point operations per second.
The Powerful, The Strong, The Fast /Harder Than Rocket Science If launching a rocket to the moon sounds tough, try flying an aircraft into space at speeds topping Mach 20
The Tall, The Deep, The Long/The Sky's the Limit Future skyscrapers will lift high-rise technology to new heights. But the economic challenges are daunting
The Tall, The Deep, The Long/To the Bottom of the Sea Offshore structures have been built in more than 3,000 feet of water. How much deeper can the technology be pushed?
The Tall, The Deep, The Long/Designer Genomes As efforts accelerate to catalogue the lengthy stretches of DNA responsible for life, scientists are getting closer to being able to build living cells from scratch
The Tall, The Deep, The Long /Bridging Borders in Scandinavia The Øresund Bridge and Tunnel will join Denmark and Sweden on July 1, 2000. Prefabrication of the project's complex components facilitated construction
The Greatest Projects Never Built Many well-laid engineering plans went astray - and in some cases, it was lucky they did
The Hubris of Extreme Engineering "Engineers can come to believe in themselves and their creations beyond reasonable limits. When failures do occur, they naturally cause setbacks but usually do not force the abandonment of dreams for ever grander and more ambitious projects."
The Oceans
Celebrating the Sea When the United Nations declared 1998 as the International Year of the Ocean, we thought it would be the ideal time to take our readers, at least vicariously, on the ultimate ocean cruise.
Atlantic Ocean The Atlantic Ocean is named for Atlas, who according to Homeric myth held heaven up with great pillars that rose from the sea somewhere beyond the western horizon.
Pacific Ocean Named by Portuguese explorer Ferdinand Magellan, who believed it to be free of violent storms, the Pacific Ocean is not, in fact, so pacific.
Indian Ocean Unlike the Atlantic or Pacific, the Indian Ocean is completely enclosed on the northern side, a configuration that gives rise to drastic seasonal changes in the winds and currents.
Polar Oceans The ice-covered Arctic was first recognized to be a deep basin only a century ago, and it remains today the most enigmatic ocean on the earth.
The Origins of Water on Earth Evidence is mounting that other planets hosted oceans at one time, but only Earth has maintained its watery endowment
Pacific Ocean: Bikini's Nuclear Ghosts The atoll survived some of the worst destruction that humankind has ever dished out to become a lush paradise once again
The Rising Seas Although some voice concern that global warming will lead to a meltdown of polar ice, flooding coastlines everywhere, the true threat remains difficult to gauge
Arctic Ocean: Forty Days in the Belly of the Beast Or, a marine geologist's account of life on board a U.S. Navy nuclear attack submarine under the Arctic ice
The Oceans and Weather The sea is as important as the atmosphere in controlling the planet's weather
Atlantic Ocean: Ten Days under the Sea Living underwater in the world's only habitat devoted to science, six aquanauts studied juvenile corals and fought off "the funk"
Enriching the Sea to Death An excess of nutrients flowing from the land into the sea has created serious environmental problems in many coastal waters. Only recently have measures been taken to forestall the worst effects
Pacific Ocean: Why Are Reef Fish So Colorful? Bright patterns on reef fish are key to astoundingly complex strategies to attract mates, repel rivals and hide from predators
The World's Imperiled Fish Wild fish often cannot withstand the onslaught of modern industrial fishing. The collapse of fisheries in many regions shows the danger plainly
The Promise and Perils of Aquaculture Whether fish farming helps or hurts wild populations remains an open question
Indian Ocean: Fishing the "Zone" in Sri Lanka Sri Lanka depends on data to protect its rich coastal fisheries, but something stronger is needed to keep the poachers at bay
Indian Ocean: Sharks Mean Business Throughout the tropics, the future of reef sharks hangs in the balance as the interests of tourism and those of commercial fishing meet head-on
Life in the Ocean The richest realm on the earth remains largely mysterious
Atlantic Ocean: The Atlantic's Wandering Turtles Newborn loggerhead turtles embark on a transoceanic crossing of thousands of kilometers. Researchers are trying to determine where they go and how they survive in the featureless blue expanse
The Mineral Wealth of the Bismarck Sea Discoveries of valuable minerals on the floor of the southwestern Pacific have renewed interest in deep-sea mining. But can metallic ores be recovered there without endangering marine ecosystems?
Pacific Ocean: An Island is Born Loihi, an undersea volcano south of the big island of Hawaii, offers geologists a fascinating glimpse of an "island in the womb"
The Evolution of Ocean Law In fits and starts, the international law of the sea has evolved to keep pace with the world's changing political, economic and environmental concerns
Exploring the Ocean Planet In this Year of the Ocean, the options range from visiting a maritime museum or aquarium to swimming with sharks, sleeping in an underwater hotel and visiting the Titanic
Women's Health
The Importance of Women's Health Securing the right to vote, controlling fertility, earning (almost) equal pay for equal work - to this list of milestones for women, add one more: being included in all federally financed health studies.
Teens and 20s Teens and 20s
Fact Sheet What women in their teens and 20s need to know
Dying to Be Thin Eating disorders cripple - literally - millions of young women, in large part because treatments are not always effective or accessible
Migraine Headaches Some 20 million women in the U.S. - nearly one in seven - suffer from migraines, making this ailment one of the most common to strike women.
Help for Victims of Rape Confronting painful memories of rape can help victims cope with the trauma
What Women Need to Know about Sexually Transmitted Diseases Left undiagnosed, STDs can be deadly. Fortunately, many people can be helped
Single-Sex Classrooms: Are They Best for Girls? Girls-only classes are gaining in popularity, but whether they help girls to learn is still an open question
Why Are So Many Women Depressed? Women may be more sensitive - physiologically, at least - to certain changes in the environment. And this responsiveness might help explain the high rates of depression in their ranks
The Female Orgasm Women can reach orgasm through a wide variety of stimuli - including fantasy alone. So why do some women seldom or never experience the thrill?
30s and 40s 30s and 40s
Fact Sheet What women in their 30s and 40s need to know
When the Body Attacks Itself Autoimmune diseases afflict women much more frequently than men
Infertility Since 1978, when the first test-tube baby was born, infertility treatments have become widespread.
The Ethics of Assisted Reproduction Medicine can do a lot to help people become parents. Sometimes, maybe too much
Get Moving Researchers debate how much exercise is enough
Searching for Preeclampsia's Cause Researchers zero in on one of the most dangerous disorders of pregnancy
What Determines the Timing of Birth? Why newborns arrive on their own schedule - not yours.
Just Say No - to Pain Today there are better choices for pain releif during labor and delivery
The Genetics of Breast and Ovarian Cancer What if you could gaze into a crystal ball and learn that breast or ovarian cancer lies in your future?
The Consequences of Violence against Women Violence is a vicious cycle that harms women and their families
Women and Alcohol Women tend to drink less than men do, but alcohol can affect them more strongly - and not just because of differences in body size.
Bad Day at the Office? Research shows that stress on the job affects women and men differently
50s and 60s 50s and 60s
Fact Sheet What women in their 50s and 60s should know
Menopause and the Brain New studies suggest that the brain may be an important player in the timing of menopause
Hormone Replacement Therapy As women of the baby boom generation are all too aware these days, bodies start to change after 50.
Smoking and Breast Cancer Cigarettes may cause more cases than the two so-called breast cancer genes combined
Heart Disease and Stroke Each year since 1984, cardiovascular diseases have killed more women than men in the U.S.
Fat Chances Given the limited success of dieting - and the risks - is it better just to stay plump?
70s and Up 70s and Up
Fact Sheet What women in their 70s and up need to know
Why Women Live Longer than Men Women around the world have a survival advantage over men - sometimes by as much as 10 years. What gives them the upper hand?
Osteoporosis It's hard to envision a thin, athletic woman as a hip fracture victim waiting to happen.
At More Risk for Alzheimer's? Scientists are studying how genes and gender interact in Alzheimer's disease
Urinary Incontinence Millions of women suffer in silence from incontinence - yet experts say the vast majority of them can be helped with proper treatment.
Having a Ball Older women share tips on enjoying a long and healthy life
Magnificent Cosmos
Giant Planets Orbiting Faraway Stars Awed by the majesty of a star-studded night, human beings often grapple with the ancient question: Are we alone?
Searching for Life in Our Solar System If life evolved independently on our neighboring planets or moons,then where are the most likely places to look for evidence of extraterrestrial organisms?
Searching for Life in Other Solar Systems Life remains a phenomenon we know only on Earth. But an innovative telescope in space could change that by detecting signs of life on planets orbiting other stars
Planetary Tour Some four and a half billion years ago, and for reasons that scientists have yet to agree upon, a flat, round cloud of gas and dust began to contract in the interstellar space of our Milky Way galaxy, itself already at least five billion years old.
Mercury The innermost planet in the solar system, Mercury has the most extreme characteristics of the terrestrial bodies.
Venus Though named for the goddess of love, Venus is more like Earth's ugly sister.
Earth That it teems with life makes Earth a precious oddity among plants- although just how odd, scientists cannot say.
Mars Mar's relative nearness, mythological connotations and even its hue have made it the favored planet of popular culture.
Jupiter Jupiter represents a departure from the four relatively tiny rock planets that precede it as we travel away from the sun.
Saturn Saturn's rings make it one of the most familiar, and spectacular, images of astronomy, not to mention science fiction.
Uranus The placid blue face of Uranus, because of the presence of methane, is quite dull compared with the hectic and variable view
Neptune Astronomers searched for an eighth planet when Uranus's observed orbit disagreed with its calculated one, leading to suspicions of a large body exerting gravitational forces.
Pluto Is Pluto really a planet? Until about six years ago, the question would have seemed silly.
Asteroids Concentrated between the orbits of Mars and Jupiter float thousand of what astronomers often call minor planets, or asteroids
Comets The word "comet," from the Greek, means "long-haired," an apt description for what may appear to be a blur or smudge in the heavens .
Fire and Light Fire and Light
SOHO Reveals the Secrets of the Sun A powerful new spacecraft - the Solar and Heliospheric Observatory, or SOHO - is now monitoring the sun around the clock, providing new clues about our nearest star
V1974 Cygni 1992: Most Important Nova of the Century This nova answered many questions during its life and raised more in death
Cosmic Rays at the Energy Frontier These particles carry more energy than any others in the universe. Their origin is unknown but may be relatively nearby
Gamma-Ray Bursts New observations illuminate the most powerful explosions in the universe
Colossal Galactic Explosions Enormous outpourings of gas from the centers of nearby galaxies may ultimately help explain both star formation and the intergalactic medium
The Ghostliest Galaxies Astronomers have found more than 1,000 low-surface-brightness galaxies over the past decade, significantly altering our views of how galaxies evolve and how mass is distributed in the universe
A Universal View A Universal View
The Evolution of the Universe Some 12 billion years ago the universe emerged from a hot, dense sea of matter and energy. As the cosmos expanded and cooled, it spawned galaxies, stars, planets and life.
The Expansion Rate and the Size of the Universe The age, evolution and fate of the universe depend on just how fast it is expanding. By measuring the size of the universe using a variety of new techniques, astronomers have recently improved estimates of the expansion rate.
The Self-Reproducing Inflationary Universe Recent versions of the inflationary scenario describe the universe as a self-generating fractal that sprouts other inflationary universes
Dark Matter in the Universe As much as 90 percent of the matter in the universe is invisible. Detecting this dark matter will help astronomers better comprehend the universe's destiny
Exploring Intelligence
Intelligence Considered What does it mean to have brainpower? A search for a definition of intelligence
How Intelligent Is Intelligence Testing Conventional measures, such as SATs and IQ tests, miss critical abilities essential to academic and professional success
A Multiplicity of Intelligences Rather than having just an intelligence defined by IQ, humans are better thought of as having eight, maybe nine, kinds of intelligences, including musical, spatial and kinesthetic
The General Intelligence Factor Despite some popular assertions, a single factor for intelligence, called g, can be measured with IQ tests and does predict success in life
For Whom Did the Bell Curve Toll? The most controversial social science book in decades shook up readers. Researchers are less easily impressed
Uncommon Talents: Gifted Children, Prodigies and Savants Possessing abilities well beyond their years, gifted children inspire admiration, but they also suffer ridicule, neglect and misunderstanding
Seeking "Smart" Drugs New treatments for Alzheimer's disease and other neural disorders are pointing to drugs that could boost memory in young, healthy individuals
The Emergence of Intelligence Language, foresight, musical skills and other hallmarks of intelligence may all be linked to the human ability to create rapid movements such as throwing
Reasoning in Animals A mounting body of evidence suggests that a number of species can infer concepts, formulate plans and employ simple logic in solving problems
Talking with Alex: Logic and Speech in Parrots Parrots were once thought to be no more than excellent mimics, but research is showing that they understand what they say. Intellectually, they rival great apes and marine mammals
Can Animals Empathize? Yes Yes: Animals that pass the mirror test are self-aware and thus can infer the states of mind of another individual; Maybe not: Even though chimpanzees pass the mirror test, they do not seem to conceive of others' - or even their own - mental states
On Computational Wings: Rethinking the Goals of Artificial Intelligence The greatest value of artificial intelligence may lie not in imitating human thinking but in extending it into new realms
Computers, Games and the Real World More than just competing with people, game-playing machines complement human thinking by offering alternative methods to solving problems
Wearable Intelligence Miniature computers built into clothes, shoes and eyeglasses may become the "smartest" new fashion accessories
Is There Intelligent Life Out There? Making first contact is equivalent to finding a needle in a haystack 35 times the size of Earth. Actively sending announcements to introduce ourselves may be the best way
The Solid-State Century
Fifty Years of Heroes and Epiphanies Human beings crave legends, heroes and epiphanies.
Part 1: Introduction The Transistor
Birth of an Era In December 1947 three researchers demonstrated a device that would change the way humankind works and plays
The Transistor This article, which appeared in the September 1948 issue of Scientific American, offered one of the earliest surveys of transistor technology. It is reprinted here in its original form.
Computers from Transistors What's Inside a Computer; How a Chip Is Made; How a CMOS Transistor Works
Diminishing Dimensions The Dimensionality of a material can be reduced by sandwiching it between two layers of another material that has higher-energy electrons.
How the Super-Transistor Works The insulated gate bipolar transistor is transforming the field of power electronics
Where Tubes Rule In a solid-state world, vacuum tubes are still secure within some very interesting strongholds
The Future of the Transistor As the transistor has grown smaller and cheaper, engineers have scoffed at theoretical barriers to its progress - so far
Integration:The Transistor Meets Mass Production Integration: The Transistor Meets Mass Production
From Sand to Silicon: Manufacturing an Integrated Circuit Tiny silicon chips make modern digital technology possible. Here's how the chips themselves are made
Profile: The Law of More Gordon E. Moore co-founded two high-tech titans but is best known for an eponymous law that may finally be nearing its limit
Technology and Economics in the Semiconductor Industry Although the days of runaway growth may be numbered, their passing may force chipmakers to offer more variety
Toward Point One Gigabit chips are now in the laboratory. But the critical technology needed for manufacturing smaller circuits confronts diminishing returns.
Mysteries of the Mind
The Mind-Body Interaction in Disease The brain and immune system continuously signal each other, often along the same pathways, which may explain how state of mind influences health
The Problem of Consciousness It can now be approached by scientific investigation of the visual system. The solution will require a close collaboration among psychologists, neuroscientists and theorists
The Puzzle of Conscious Experience Neuroscientists and others are at last plumbing one of the most profound mysteries of existence. But knowledge of the brain alone may not get them to the bottom of it
The Pursuit of Happiness New research uncovers some anti-intuitive insights into how many people are happy - and why
Manic-Depressive Illness and Creativity Does some fine madness plague great artists? Several studies now show that creativity and mood disorders are linked
Depression's Double Standard Studies from 10 nations reveal that the rates of depression among women are twice as high as they are among men. Do women have a biological bent for depression, or are social double standards the major cause?
The Meaning of Dreams Dreams may reflect a fundamental aspect of mammalian memory processing. Crucial information acquired during the waking state may be reprocessed during sleep
Emotion, Memory and the Brain The neural routes underlying the formation of memories about primitive emotional experiences, such as fear, have been traced
The Neurobiology of Fear Researchers are teasing apart the neurochemical processes that give rise to different fears in monkeys.The results may lead to new ways to treat anxiety in humans.
Phantom Limbs People who have lost an arm or a leg often perceive the limb as though it were still there. Treating the pain of these ghostly appendages remains difficult
Autism Autistic people suffer from a biological defect. Although they cannot be cured, much can be done to improve their lives
Seeking the Criminal Element Scientists are homing in on social and biological risk factors that they believe predispose individuals to criminal behavior. The knowledge could be ripe with promise - or rife with danger

Compiled by Dave Lo, article summaries © Scientific American