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Designing An Atom-Bomb Powered Spaceship

by peter rowe
SAN DIEGO, Calif. — With the space shuttle on its final mission, Americans have been reliving our adventures in space: John Glenn orbiting the earth in 1962; Neil Armstrong walking on the moon in ‘69; even Mike Fincke and Greg Chamitoff floating outside the International Space Station last week.

All very historic, thrilling, inspiring.

And, for at least one local observer, deeply disappointing.

“It’s a shame we didn’t do far more in the last 30 years,” said Kedar “Bud” Pyatt.

	Kedar “Bud” Pyatt, in his La Jolla home – Image credit: Nelvin C. Cepeda. Enlarge

Fifty years ago, Pyatt was a central character in a largely forgotten chapter in America’s space saga, one that unfolded on the La Jolla campus of General Atomic. In America’s space saga, Project Orion is the most jaw-dropping road not taken to the stars.

Orion was massive: designers envisioned a spacecraft of up to 8 million tons, a city in flight.

Orion was bold: powered by nuclear detonations, the ship could voyage to Jupiter and back.

Orion was serious: at General Atomic, Einstein-level geniuses pursued this unlikely enterprise for five years, annually winning $1 million to $2 million — the equivalent of $7.5 million to $15 million today — in federal grants.

Decades later, Orion can still enthrall: “Absolutely,” said Pyatt, 78, now living in semiretirement in La Jolla. “I think it makes a lot of sense.”

Even some who dismissed this scheme as senseless found it irresistible.

While we can’t see Orion — it was never built — it would have been quite a sight. Compare dimensions from the proposed “Super Orion” with those of the space shuttle:

• Mass, Super Orion: 8 million tons
• Mass, Space shuttle: 2,030 tons

• Diameter, Super Orion: 400 meters
• Diameter, Space shuttle: 8.7 meters

• Fuel, Super Orion: nuclear bombs
• Fuel, Space shuttle: chemicals, including liquid hydrogen

Sources: “Project Orion,” George Dyson (Henry Holt and Co., 2002); NASA

“It is in many ways the ultimate Fanboy fantasy — it is just too cool, a really big spacecraft detonating nuclear weapons to go really fast,” said Dwayne A. Day, a Washington-based space historian with the National Research Council.

Orion, though, was doomed. The project never quite escaped its early connections to the Air Force, and a new civilian agency — NASA — took control of the space program and set its own course. Orion faced too much competition — and too many qualms.

“It was,” Day maintained, “bordering on … insane.”

starter’s pistol

Most trace Orion back to 1945 and Stanislaw Ulam, one of the brilliant figures behind the United States’ Manhattan Project. “It was typical of Ulam to be thinking about using bombs to deliver missiles,” wrote George Dyson in his 2002 history, “Project Orion,” “while everyone else was using missiles to deliver bombs.”

This idea, later refined by a General Atomic team led by Theodore Taylor, one of Ulam’s colleagues, and Dyson’s father, Freeman Dyson, was prompted by the fact that standard rockets are limited by their fuel. Sending a one ton payload to the moon, for instance, requires many more tons of rocket fuel.

Nuclear fission, though, converts matter into energy in a vastly more efficient way. By harnessing that power, a rocket could travel much further — even to the ends of the solar system.

In theory. Few seemed interested in testing that theory until 1957, when the Soviet Union launched the world’s first artificial satellite. Sputnik acted as the starter’s pistol for the space race. With Washington determined to catch up, the Pentagon went shopping for scientists.

“When I was in graduate school,” said Pyatt, who earned a Ph.D in nuclear physics from Yale, “I had to beat down the offers of money. The Department of Defense opened the floodgates with money.”

A faculty adviser steered Pyatt to Southern California, where some of the money was flowing into a new research center, General Atomic (then a division of General Dynamics; it was later renamed General Atomics). Coming to La Jolla in September 1959, the young physicist spent the next four years working on Orion’s radical propulsion system.

Elements of Orion were tested all around San Diego — a small model was launched in Point Loma, using 60 grams of C-4, a plastic explosive, rather than nuclear devices. But in the fall of 1963, Pyatt packed for Kwajalein, a remote Pacific atoll where he was to supervise a nuclear blast that would test the theories behind Orion.

His journey was indefinitely postponed. While General Atomic planned Pyatt’s trip, President Kennedy signed a treaty banning atomic detonations in the air, underwater or in space, effectively ending Project Orion.

“As much faith as I had in my own calculations,” Pyatt said, “nobody else would have had my faith in this unless we had gone out and shown that it works. And I don’t blame them.”

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Today, without a robust manned space program ready to replace the shuttle, Orion’s galaxy’s-the-limit spirit seems long ago, far away and far, far out.

“In retrospect,” said Burt Freeman, 86, a Tierrasanta resident who worked on both the Manhattan and the Orion projects, “it was a really crazy idea.”

The obstacles were as large as Orion’s solar-system-spanning mission. The spaceship was to be hurled aloft by expelling and then detonating small nuclear devices; the blast would slam into plates shielding the ship’s stern. But what would shield the earth from the fallout?

Taylor argued that the radiation, like the bombs, would be small. Besides, Orion could be launched from the dark side of the moon, using bases which he believed would be built by 1980.

Headlines in The San Diego Union and Evening Tribune, both ardent supporters, charted Orion’s trajectory.

Oct. 28, 1959: “Atomic Rocket Engine Called ‘Promising’”

May 28, 1961: “Nuclear Rocket Project Speeded”

March 23, 1964: “S.D. Expert Asks More Orion Funds”

Jan. 8, 1965: ”Orion Project Unwanted Child of Space Program”

Initially an Air Force program, Orion had been inherited by a new federal agency with other priorities.

“Orion was turned over to NASA,” Pyatt said, “and NASA gave it the back of its hand.”

Moreover, other proposed nuclear-powered rockets such as Project Rover were competing for funds and headlines. Still, General Atomic’s ill-fated venture stood out for its intellectual rigor and daring.

“A great deal of force of personality and intellect drove this project,” Burt Freeman said.

Taylor and many other Orion veterans have died; some of the living have reconsidered. Freeman Dyson, for instance, now advocates spacecraft powered by solar winds. In May, though, Pyatt co-authored a paper for NASA’s Jet Propulsion Lab about reviewing and possibly updating the research conducted a half century ago in La Jolla.

The physicist hasn’t heard back from NASA. He’s not optimistic about the future of American space exploration.

“I despair, actually,” he said.

Orion, crazy? In Pyatt’s view, the real insanity would be to turn our backs on an infinitely vast, and almost entirely unexplored, frontier.

This article first appeared in the San Diego Union-Tribune. © Copyright 2011 The San Diego Union-Tribune, LLC All Rights Reserved. Reprinted by Permission.

Tags: General Atomic, JPL, NASA, Project Orion, Space, spacecraft, spaceflight