In October 1997, NASA is scheduled to launch the Cassini space probe and with it the largest amount of plutonium ever used in a space device. The Cassini probe with 72.3 pounds of plutonium-238 fuel aboard, will ride on top of a Lockheed Martin-built Titan IV rocketÄa number of which have exploded in the atmosphere.

Plutonium is the most toxic substance known. "One pound, if uniformly distributed, could hypothetically induce lung cancer in every person on Earth;" notes Dr. Helen Caldicott, founder of Phisicians for Social Responsibility.

The Global Network Against Weapons and Nuclear Power in Space is holding a national meeting in FloridaÄincluding a protest demonstration at Cape CanaveralÄnext Saturday to "stop this sheer and utter madness," said Bruce Gagnon, the Network's co-coordinator.

NASA plans to send Cassini hurtling back to Earth for a "swingby," to give it the velocity to get to Saturn. It is supposed to buzz the Earth in 1999 at 42,300 mph and at a height of 312 miles. But if Cassini comes in too close during this "slingshot maneuver" and there is an "inadvertent re-entry," the space probe could break up in the Earth's atmosphere, raining plutonium back down on the Earth's surface.

If that happens, NASA's "Final Environmental Impact Statement for the Cassini Mission" acknowledges: "Approximated 5 billion of the estimated 7 billion to 8 billion population ... could receive 99 percent or more of the radiation exposure."

The United States has sent 24 nuclear devices into space with a failure rate of 15 percent. Accidents happen all too often. A plutonium-fueled power system-was aboard the ill-fated Apollo 13 mission that crash-landed in the Pacific. The next mission of the ill-fated Challenger was supposed to carry up a space probe with 25 pounds of plutonium.

There's no reason to risk sending plutonium on spacecraft. The European Space Agency in 1994 announced a breakthrough in the development of "new, high-performance silicon solar cells for use in future demanding deep-space missions" to replace plutonium-fueled generating systems. With support and a little time, the European Space Agency could have solar cells ready for a Saturn mission.

But NASA; the U.S. Department of Energy, the national nuclear laboratories, and the corporations that produce nuclear hardware for space missions, insist on staying with nuclear.

There are other nuclear-fueled space projects on the drawing boards. The Sandia Laboratories plan to develop nuclear-powered satellites to beam TV signals down to Earth; Topaz II Russian-made reactors, purchased by the United States for use on orbiting battle platforms of "Star Wars," are being ground-tested by the Air Force; an Air Force program proposes to use nuclear reactors for power and propulsion for military satellites, and NASA plans for a nuclear-powered colony on the moon.

We must stop the government's reckless and costly plans to use nuclear technology in space. If one pound of plutonium could give everyone on Earth cancer, how much damage could inflicted if something goes terribly wrong with the Cassini space probe, and its 72 pounds of plutonium scatters all over the world?

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