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Teaching at the End of the World

The professor who tapped into a ­doomsday scenario to teach advanced space systems engineering

Paul Sandorff ’39 did not look like a harbinger of doom. A wiry Lockheed Martin employee with short-cropped hair and an affinity for meteoroids, he had been teaching at the Institute for nearly 15 years in February 1967, when he asked his students to prevent the world from being destroyed on June 14, 1968.

Paul Sandorff teaching
Paul Sandorff ‘39 asked his students how they’d stop a mile-wide asteroid if it really had been hurtling toward Earth.

Fourteen years earlier, University of California astronomer Samuel Herrick had projected that a mile-wide asteroid known as Icarus (named for the mythological figure who flew too close to the sun) would pass relatively close in the summer of 1968. Graphs plotting Icarus’s orbit showed the asteroid approaching at some 19 miles per second until it came within four million miles—nearly 17 times the moon’s distance, but still closer than all but three contemporary celestial bodies had advanced toward our planet. “A change of only a few degrees in the position of the descending node of Icarus’ orbit … would make it possible for Icarus and the earth to be at the same place at the same time,” Scientific American reported. Under those circumstances, Icarus could have been expected to crash into Earth with nearly 40 million times the force of the Hiroshima bomb.

Sandorff was teaching advanced space systems engineering the year before the asteroid’s near approach, and he capitalized on the sensation to create a project he called “Mission to Icarus.” For the purpose of the class, Sandorff told the students to assume that Icarus was in fact on course to strike. Destruction was imminent. The students had two class periods a week, February through May, to figure out how to save the world. The syllabus poured on the drama: “Clearly, Icarus must be stopped. No effort or funds will be spared in carrying out the detailed plan to be developed by the crack team of scientists and engineers assigned to the project … The problem solution may utilize a rocket to intercept the asteroid and nudge it from its course. Alternatively, it may be better to reduce it to rubble with a nuclear warhead.”

The challenge had been issued. Solutions had been suggested. It was up to the students to determine the strategy.

The class split into seven technical groups devoted to orbits, trajectories, celestial mechanics, and astronomy; boosters and propulsion; nuclear payloads; space vehicles; navigation, guidance, and control; communications; and planning and management. Sandorff assigned the Scientific American article and readings on such topics as meteor craters and the catastrophic effects of collisions in space. He supplemented these with reports from companies like General Dynamics, which sent its summaries of the test launches of the Atlas-Centaur, an expendable launch system designed to carry payloads into space.

A star roster of guests contributed. Herrick, known to the research community as “Mr. Icarus,” sent a reprint of his famous paper “Icarus and the Variation of Parameters” and flew from California to meet the class. John S. Kelly, director of the Division of Peaceful Nuclear Explosives at the U.S. Atomic Energy Commission, mailed a table indicating the explosive power of different sized bombs. And Fred Whipple, director of the Smithsonian Astrophysical Observatory, led an afternoon talk on the features and properties of the asteroid. In addition, 18 students traveled to Patrick Air Force Base in Florida to see the rockets they were considering. As Sandorff noted in a letter to a base official, “I know that the experience will make their studies much more realistic.”

Icarus didn’t stand a chance. At the end of the semester the class shared its recommendations in Kresge Little Theater with an audience of aerospace academics and a writer from MIT Technology Review. In a three-hour presentation, rehearsed twice before the final show, the students proposed six separate launch missions to blow apart the asteroid. Four of NASA’s Saturn V rockets would be launched to deflect the asteroid’s path, and two more would finish the job by exploding thermonuclear bombs. Icarus would be blown off course and smashed to bits. In dramatic fashion, they would save the world less than a day before the expected collision. They estimated that the mission would cost $7.5 billion and projected with 71 percent probability that it would prevent any part of the asteroid from reaching Earth.

“Mission to Icarus” remains little more than a memory, but the fascination with Earth-bound asteroids continues. In 2012, MIT graduate student Sung Wook Paek proposed that a future collision might be deflected by blasting the asteroid with paintballs—just in time for Icarus’s next close approach in June 2015.

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