Saturday's space shuttle disaster has stirred grassroots opposition to the Bush administration's recently announced plan to develop nuclear-powered space rockets.

"If there had been a nuclear reactor on board (the Columbia space shuttle), this debris field they're warning people not to come too close to would be a considerably bigger mess," said physicist Edward Lyman, head of the private Nuclear Control Institute in Washington, D.C.

But many space enthusiasts say nuclear-powered spaceships offer the only way to penetrate the deepest, darkest corners of the solar system. Out there, billions of miles from Earth, sunlight is too weak to energize existing forms of solar-electric cells.

Development of nuclear-powered spaceflight would also allow much faster travel across the solar system, advocates say.

In October, NASA announced a contract with Boeing Corp.'s Rocketdyne division in Canoga Park (Los Angees County) to develop nuclear power for space uses and fulfill the "nuclear systems initiative" advocated by NASA chief Sean O'Keefe. The initial Boeing project will cost about $7 million over 3 years, while the overall initiative is expected to consume about $2 billion in federal research funds over a decade.

Nuclear-powered spaceships would constitute a "quantum leap forward" in cosmic exploration, akin to "the difference between a powered ship versus a sailboat, or the difference between a powered airplane and a glider," says nuclear engineer Mike Jacox of Texas A&M University. "A nuclear reactor power system would allow us to go to the edges of the solar system and beyond."

NOT THE RIGHT STUFF

But after Saturday's space tragedy, an anti-nuclear activist group, the Florida-based Global Network Against Weapons and Nuclear Power in Space, urged an end to the development of nuclear space projects.

Had a nuclear reactor been aboard the Columbia, the result would have been "a Chernobyl in the sky," said veteran anti-nuclear activist Karl Grossman, the author of "The Wrong Stuff: The Space Program's Nuclear Threat to Our Planet."

Despite anti-nuclear activists' concerns, NASA and corporate officials stressed that safety will be a paramount concern as they develop space nuclear power.

"Safety is our No. 1 priority. Nothing proceeds without complete and utter commitment to safety," Dan Beck, a spokesperson for Boeing, one of the firms developing space nuclear power systems, said in a phone interview Monday. A NASA spokesperson, Don Savage, agreed, stressing that safety "is our biggest job in that (nuclear) program."

Jacox, one of numerous experts who are helping NASA develop nuclear power for space uses, rejects anti-nuclear activists' nightmare vision of a Columbia- type nuclear disaster, in which a spaceship burns up on re-entry to Earth's atmosphere.

"No one has ever proposed (deliberately) re-entering a nuclear reactor that has any significant radiological hazard," Jacox explained. "It's very different to have a nuclear reactor that operates in deep space versus an accident (in low Earth orbit) involving the shuttle."

Jacox and his colleagues dream of a space-based nuclear reactor that would heat gas to extremely high temperature, then expel it from a rocket nozzle.

In the past, NASA has launched several deep-space probes that are powered with plutonium. Space agency officials say their tests show that in the event of a space shuttle explosion, akin to the 1986 destruction of the shuttle Challenger, the plutonium wouldn't disperse enough to pose a significant health threat.

Anti-nuclear activists aren't reassured, though. "What most people don't know is (that the shuttle mission after Challenger) was scheduled to be carrying a satellite powered by 46.7 pounds of plutonium.

"About seven-thousandths of an ounce of plutonium is enough to constitute a lethal dose if someone inhaled it and it got stuck in their lungs," said Lloyd Dumas, a professor of political economy at the University of Texas at Dallas and author of "Lethal Arrogance: Human Fallibility and Dangerous Technologies."

EARLY ATTEMPT ABANDONED

Ever since the dawn of the atomic age in the 1940s, many space buffs have dreamed of crisscrossing the solar system -- perhaps even nearby star systems - - in nuclear-propelled rockets. In the 1960s, the United States tried to develop a nuclear rocket as part of Project Nerva and conducted experiments at the Nevada Test Site. The government eventually abandoned the project.

Dreams of nuclear-assisted spaceflight were shaken in the 1970s, when a Soviet satellite with an on-board atomic reactor fell on Canada. It left a radioactive debris trail that triggered scary headlines around the world.

Ever since, nuclear enthusiasts have struggled to revive interest in space nukes.

©2003 San Francisco Chronicle

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