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The Daily Beast

When 60 Minutes’ Hysteria Nearly Shot Down a NASA Mission to Saturn

NASA/JPL-Caltech/Space Science Institute via GettyFew impediments could have been more severe. For a spacecraft to reach the Jovian system with enough speed to eventually achieve orbit around Europa, it had to either launch from a powerful rocket (which NASA lacked, limiting spacecraft to a space shuttle deployment) or be absurdly light (which the required radiation armor rendered impossible). JPL engineers dashed out hastily written equations in chalk before driving fists against blackboards in fits of despair.Nothing for NASA was ever free… except for gravity assists. Ordinarily, the agency could compensate for the meager speeds of heavy spacecraft by taking indirect flight paths and using planets encountered along the way to yank and shove the robotic pilgrim outward, inward, or onward. The laws of physics being immutable, and the salient numbers known, NASA’s orbital dynamicists could do this all day, running the numbers to sling spacecraft precisely, one planet to the next: free propulsion from Isaac Newton. It was incomparably the best bargain in space exploration.But then television tabloid journalism got involved, and everything became complicated.In 1997, while waiting at Cape Canaveral for liftoff, the Cassini mission was beset suddenly by political protest. Cassini carried three radioisotope thermoelectric generators, which were powered by the decay of plutonium
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