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The Golly Gee-Whiz Atomic Spaceship

The forgotten quest to build a rocket propelled by thousands of hydrogen bombs

By Tim Folger

Project Orion: The True Story of the Atomic Spaceship By George Dyson Henry Holt and Company, $26

The race into space was on, and the United States was losing. The Soviet Union launched the 184-pound satellite Sputnik in October 1957 and just one month later sent a dog into orbit on Sputnik II. The United States followed in January 1958 with the 31-pound satellite Explorer I. Even as the nascent U.S. space program focused on pint-size payloads, however, a research team at an obscure division of the General Dynamics Corporation was secretly drawing up plans for a monstrous 4,000-ton spaceship that would be powered by the sequential explosions of thousands of hydrogen bombs and would ferry hundreds of astronauts at a time across the solar system. Indeed, the physicists who worked on the project were so confident their design would be a success that they adopted an ambitious motto: "Saturn by 1970."

The gargantuan Orion spaceship never made it past the blueprint stage, much less to Saturn. Nonetheless, until the project was shut down in 1965, some of the nation's best scientists chased what now seems a patently ridiculous dream. Among them was physicist Freeman Dyson, whose son George recounts the rise and fall of the effort to build a bomb-powered spaceship in his new book, Project Orion. While Dyson's language is at times awkward and his chronology confusing, the sheer outlandishness of the forgotten space endeavor is nothing less than fascinating.


The basic Orion design: Helix-shaped containers house hydrogen bombs, to be ejected through a hole in its "pusher plate," at bottom.Photograph courtesy of Henry Holt and Company

Nearly all the Orion scientists Dyson interviewed fondly recall the excitement that surrounded the project. The late 1950s and early 1960s was an era when the United States and the Soviet Union, unrestricted by any treaty, exploded huge hydrogen bombs in the atmosphere. Both nations were building nuclear-powered ships and submarines. Why not an enormous bomb-driven spaceship? With only conventional rockets humans might travel as far as Mars but no farther. For Dyson's father and his fellow physicists, the lure of building a spacecraft that could travel to the moons of Saturn and back within four years was irresistible.

The favored design called for a heavily shielded, bullet-shaped spacecraft as tall as a 10-story building, mounted on four 20-foot-long shock-absorbing columns. Attached to the base of the shock absorbers was a thousand-ton disk-shaped "pusher plate." Hydrogen bombs were to be ejected from the ship—at a rate of about one every second—through a hole in the center of the pusher plate. The bombs would detonate about 100 yards from the ship. The blasts from successive explosions would smash against the plate and accelerate the ship.

A three-foot-tall prototype powered by conventional explosives was flown to a height of 185 feet, demonstrating, to the project's supporters at least, the plausibility of the idea. But before the Orion team could build a prototype with nuclear bombs, the atmospheric test ban treaty of 1963 killed the project.

Much about Orion remains classified even today. The research led to advances in the design of compact nuclear weapons and in funneling the energy of their explosions, secrets the military jealously guards to this day. Some physicists still won't dismiss the idea of a bomb-powered ship, arguing that it could be stationed in orbit, eliminating the dangers of atmospheric contamination that plagued the original Orion. Such a ship would open up the solar system, and perhaps the stars, to human exploration. It might even be used to destroy an asteroid on a collision course with our planet. Four decades after working on Orion, physicist Bud Pyatt insists that the project was simply ahead of its time. "It would have worked," he says now. "Even in my dotage, I'm a true believer."

From Project Orion, p. 79:

' . . . the whole thing looks feasible except for the very serious objection that during the initial liftoff from the earth and while in the dense atmosphere the entire vehicle is immersed within the weapon fireball . . .'


Can Whiplash Climate Changes Explain the Ape-to-Man Jump?New evidence points to radical shifts in the weather as the surprising catalyst for human evolution

By Corey S. Powell

A Brain for All Seasons: Human Evolution & Abrupt Climate Change

By William H. CalvinUniversity of Chicago Press, $25

We frequently get letters at Discover from skeptics who question the notion that humans have descended from apes. And we have to admit that even dedicated Darwinians are baffled by a conundrum of evolution: How did humans diverge so sharply and rapidly from other primates and emerge as large-brained, chatty, and sociable? William Calvin, a behavioral scientist at the University of Washington, offers a surprising answer in A Brain for All Seasons: Blame the weather.

The basic theory of natural selection suggests that evolutionary change grows out of the random variations found in any population. Depending on local conditions, some organisms will be more successful than others: They might have slightly thinner fur, smaller teeth, or some other traits that prove beneficial. The average form and features of the next generation will be slightly different because of unequal survival rates, and the cycle repeats. Scientists traditionally pictured this process happening in a leisurely manner, nudged along in part by gradual environmental shifts. Beginning in the mid-1980s, however, a number of researchers recognized that Earth's climate sometimes changes drastically in just a few years. Those crazy times, Calvin argues, are the key to understanding human origins.

During whiplash climate changes, temperatures plunge and horrible droughts set in. Calvin envisions groups of hominids migrating to shriveled lakes and watering holes, drawn by the concentration of game animals. In such relatively compact social settings, altruism might have been a useful strategy for those protohumans able to recall which individuals had shared fairly and which had not. The herds of prey loitering around the watering hole might also have encouraged cooperative, semiskilled hunting by using what Calvin describes as Killer Frisbees—the enigmatic triangular stones with sharpened edges found at many hominid fossil sites. Ecological crises occurred repeatedly over the past two and a half million years, especially during the ice ages of the last 117,000 years. Each swing of the climate weeded out large parts of the population, favoring the large-brained hominid generalists who could survive when water was scarce and then thrive in the lush savanna once the rains returned.

All of this is necessarily speculative. Many behaviors do not leave any traces, and fossils are much more effective at recording what happened rather than why. Calvin addresses these uncertainties and invites readers to examine his evidence by structuring the book as a travelogue. You join him as he watches the animals around a Masai watering hole, observes sea ice floating off Greenland, and accompanies a fossil excavation in the Sterkfontein Grotto of South Africa. The flood of information is persuasive, if a little overwhelming.

Why don't we see great leaps in primate evolution now? One part of the answer is that major changes generally take a long time for slow-reproducing creatures like ourselves. But radical climate changes could quickly do a number on us, Calvin warns: "The result would be a population crash that would take much of civilization with it, all within a decade."

From A Brain for All Seasons, p. 8:

We could go back to ice-age temperatures within a decade—and judging from recent discoveries, an abrupt cooling could be triggered by our current global-warming trend. Europe's climate could become more like Siberia's.


Kilimanjaro: To the Roof of AfricaIMAX MovieDirected by David Breashears

For days the intrepid climber has struggled up the slopes of Mount Kilimanjaro. His journey, begun in the moss-draped rain forests at the foot of the mountain, has led him upward through heaths, moorlands, and alpine deserts into the embrace of clouds. The peak, capped in snow and glacial ice, lies above and still ahead. Our protagonist yearns to rest. He yearns to reach the top. He yearns for soap. "I'm kind of smelly," he says. "And I think also the others haven't bathed."

That's Hansi Mmari, age 13, one of several amateur adventurers who enliven Kilimanjaro: To the Roof of Africa, the latest IMAX feature from filmmaker David Breashears. Standing 19,340 feet tall, Kilimanjaro is only two-thirds as tall as Everest. But what it lacks in stature, Kilimanjaro more than makes up for with its rich natural history. It rose 360,000 years ago from the Great Rift Valley, a vast tectonic divide that runs through East Africa, and grew to become the largest volcano (now a dormant one) on any continent.

Kilimanjaro's slopes span the climatic range, from tropical to arctic; climbing from base to peak "is like walking from the equator to the North Pole in only a week," as one trekker in the film says. Average temperature and rainfall drop steadily as the elevation rises: Lush forests give way to exposed heaths bright with wild irises and gladioli, which turn to boggy moors. These moorlands at the upper reaches of the mountain are a battle zone for plants; lobelias and groundsels have developed ingenious tactics to preserve moisture in an environment where the soil freezes at night and the sun's rays scorch them by day. Above 15,000 feet there is virtually no life at all, only statuesque glaciers that never melt but simply evaporate directly into thin air under the tropical sun. And there are signs of lowland visitors: leopards, eland, elephants whose bones suggest they wandered up for the view and stayed for eternity.

These natural wonders are revealed gracefully through a human adventure, the story of five amateur mountaineers who, like 11,000 other people a year, attempt to reach Kilimanjaro's summit. The film isn't a true documentary; the trek team was handpicked by Breashears to represent a diversity of perspectives. There's the Tanzanian boy, Hansi, and a 12-year-old girl from Massachusetts who has longed to climb Kilimanjaro since, oh, forever. Also in tow are a 55-year-old British geophysicist, a 64-year-old writer of mountaineering books, and a 23-year-old Danish model and painter whose "extroverted nature inspired her comrades," or so say the filmmakers. Their guide, Jacob Kyungai, who grew up in a village at the base of Kilimanjaro and has climbed the mountain more than 250 times, provides the film's sonorous narration.

Their story does seem, at times, overly contrived. The trekkers are revealed largely through voice-overs, and much of that material is obviously scripted. Surely not even the most articulate geophysicist tosses off a remark like, "Scorching rivers of lava poured down these slopes, and eruptions lit up the night sky." Nor is it likely that a Danish model with otherwise fractured English would say, in casual conversation, "In such thin, dry air, this ice is completely exposed to the intense rays of the tropical sun. That, along with the sculpting force of the wind, creates phenomenal shapes." And the musical score could have done with a few less trumpets. Why does every new IMAX film score sound like the theme to Bonanza?

On the other hand, the film is a splendid mix of cinema vérité and big-screen grandeur. The trekkers are given enough impromptu lines (on the subject of body odor, for instance) to reveal some real personality. And the hard work of hiking uphill is all theirs, not some camera trick. Anyway, the point of an IMAX film is to be larger than life. When the view is as stunning as what Kilimanjaro offers, mere plot devices pale in comparison. — Alan Burdick

This is an extended version, exclusive to the Discover Web site, of the article that appears in Discover Magazine.



The TopsBeyblade, $6.99; Blizzard, $15; Bearing King, $15.99; Brass Quark, $49.95; Tungsten Quark, $149.95

The simple gyroscopic motion of toy tops has been a source of hypnotic appeal since time immemorial. But the latest tops are a far cry from the small clay cylinders that mesmerized children in ancient Rome and Greece. Take the combat-ready Beyblade ($6.99,, which inspired a Japanese cartoon featuring gladiator-style battles with spin tops, and which should be hitting North American TV line-ups this year. Powered by a plastic rip-cord launcher, the saucer-shaped Beyblade measures about an inch and a half across. It comes equipped with mix-and-match components, including attack rings with various spikes and flanges designed to knock other tops out of a plastic arena that comes in three sizes, ranging in width from 16 to 213/4 inches. Interchangeable bases with different-shaped points affect the spin motion; a duller point, for instance, increases the friction so that the top skitters in a helter-skelter fashion.

Old-fashioned string-wound peg tops tricked out with independently rotating tips are the rage with the skateboard-and-dirt-bike crowd. Duncan Toys representative Steve Brown, a competitive spinner, can release a top, snare its tip back on the string, twirl the top over his head, slide it in a spiral down his arm, and then continue spinning it in his hand. Tricks in the hand are better done with a ball bearing-equipped top, where the tip stays put while the top spins. "That reduces friction and adds a ton of spin time in your hand," says Brown. Aspiring stunt spinners can experiment with the Spintastics Blizzard ($15, or the Duncan Bearing King ($15.99,, shown at left. YoYoJam has the Double Tip Bulldog ($15, and TopDog ($28), specially shaped to have ball bearing points at both ends to really let you flip the top around.


Photograph courtesy of Duncan Toys

Egged on by the super tricks in Duncan's "How to be a Player" video ($17), and Spintastics' "Spinology" instruction video ($15), I talked Brown into giving me a personal lesson at New York's Toy Fair. He showed me how to hold one end of a 60-inch-long string at the wide part of the top, then hook it around the tip and wind it tightly around the body of the top. A plastic "button" on this end of the string slips between two fingers. He explained that I had to keep the tip pointing straight up as I threw it, as the action of the string popping off the tip flips the top over 180 degrees. But the button came out of my hand and the whole thing landed in a tangled heap on the floor. Brown put his hands on his hips and looked at it, then peered at me in mock disgust. He scooped up the top, wound it again, and handed it back to me. This time I managed to hold the string and get the top spinning, but it wobbled uncontrollably. Brown was encouraging -- he told me I just had to follow through on my throw more.

Brown says his unofficial record for keeping a top spinning is three hours, but that's done by using the string to regenerate the spin on the top. "Actually the peg top is poorly designed to spin well because all the weight is up high," says Don Olney, founder of The Toycrafter, a toy store that specializes in tops, and owner of about 7000 tops. Olney has come up with some alternate top games. Swirlarounds ($5.55) and Magnetops ($5.00) from The Toycrafter ( have a magnetic tip, so they can be suspended upside-down from a metal object, such as a bent paperclip, and spun gently. Tilt the paperclip slightly and the tops will follow its labyrinthine twists without running off the end. The A Maze 'N' Tops ($7.50) have a small plastic top that has to be guided through the cut-out path of a maze on a wooden board before it runs out of spin.

For spinners in quest of a top that just keeps on going, Jim Lewis of Micro Logic Corporation developed the Quark Top ( The name is a play on the top quark subatomic particle, which has both mass and spin. "I'm interested in machining, so I did one just for fun," says Lewis. "And then I started thinking, I wonder how you can engineer this to really get the longest spin time." His models have a light plastic core and a heavy rim made of brass ($49.99, shown at far left), heavier tungsten ($149.99), or gold (custom-made for $2,495). Added weight in the rim increases the top's angular momentum, allowing it to spin longer. To perfect the top's balance, the Quark Top comes with a laser pointer that bounces a laser beam off the spinning rim: If the reflected laser beam shows up as a dot on the ceiling, the top is perfectly balanced; if it appears as a small circle, the top is wobbling, and the weight distribution must be adjusted by adding small washers to slots in the top's underside. "I can probably balance the top in about two minutes," says Lewis, "but for a new person it could take 20 minutes." Perfectly calibrated, the brass top will spin for 15 minutes, the tungsten for 22 minutes. Lewis isn't sure how long the gold top will spin: He's waiting for someone to order one so he can find out. — Fenella Saunders


Phineas Gage: A Gruesome but True Story About Brain Science

By John FleischmanHoughton Mifflin Company, $16

A freakish accident turned Phineas Gage, a railroad construction foreman, into an unwitting pioneer of modern brain science. On September 13, 1848, in Cavendish, Vermont, Gage was preparing black gunpowder for blasting when his tamping rod—a 3-foot-7-inch, 131/2-pound iron bar—unexpectedly slipped from his hands and struck a spark. The resulting explosion shot the iron like a missile straight through his head. Remarkably, Gage never lost consciousness and survived another 11 years. But he underwent a startling personality transformation, turning strangely profane and unpredictable. His case astonished doctors and offered some of the first insights into the relationship between personality and the workings of the brain's frontal cortex.

In Phineas Gage: A Gruesome but True Story About Brain Science, an illustrated volume intended primarily for young readers (ages 10 and up), author John Fleischman weaves fascinating science into a stylish narrative that is likely to pique the curiosity of adults too. Fleischman provides a fascinating glimpse of 19th-century medical practices. But he also explores contemporary research related to the Gage case.

Antonio and Hanna Damasio, husband-and-wife brain researchers, study changes in the brains of patients who, as the result of drastic surgeries to remove tumors deep in the cortex, sustain neurological damage that makes them emotionally unstable. In 1994 the Damasios constructed a postmortem brain scan of Gage to see if they could precisely map the damage to his cortex. After taking measurements of his skull, which resides at Harvard Medical School, they devised a computer model of his brain and generated 16 possible paths that the tamping iron could have taken. Their final model suggests that the rod caused extensive damage in the ventromedial region, which regulates moods and many cognitive functions, but bypassed the area of the frontal cortex that controls speech, as well as several other regions that integrate sensory input and muscle activity.

Exactly 150 years after the tamping rod bored a hole in Gage's head, neurologists from around the world gathered near the site of the accident to discuss frontal cortex injuries. At the end of his life, Gage was shunned by his neighbors. But at the conclusion of the conference, Cavendish town fathers unveiled a plaque commemorating his contribution to medical science. Gage's battered skull was driven up from Harvard just for the occasion, cradled in the back seat of a limousine. — Deborah Hudson

Science Best-sellers



The Universe in a NutshellBy Stephen Hawking, Bantam


The Future of LifeBy E. O. Wilson, Knopf


The Structure of Evolutionary TheoryBy Stephen Jay Gould, Harvard University Press


How to Build a Time MachineBy Paul Davies,Viking


Uncle TungstenBy Oliver Sacks, Knopf


The Skeptical EnvironmentalistBy Bjørn Lomborg, Cambridge University Press


Synaptic Self: How Our Brains Become Who We AreBy Joseph Ledoux, Viking


Genes, Girls and Gamow: After the Double HelixBy James D. Watson,Knopf


Six Easy pieces & Six Not So Easy PiecesBy Richard Feynman, Perseus


The Birds of Heaven, Travels with CranesBy Peter Matthiessen, North Point Press

* Source: Barnes & Noble Booksellers

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Learn about new propulsion systems NASA is cooking up: y2000/ast11apr_1m.htm.

For top tricks and tips, see and

The International Top Spinner's Association is

The 2002 World Yo-Yo Contest is held in August in Florida and has a top spinning division:

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