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Death by Asteroid: A Graphic Look at Rocky Threats from Space

What we don't know could hurt us


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Graphic and research by Paul Chodas, NASA Jet Propulsion Laboratory

Researchers have identified more than 2,300 asteroids and comets that are big enough to cause considerable damage on Earth and could possibly hit us. These “potentially hazardous objects” look ominous on the flat plot here, but because they travel in three-dimensional orbits, the perfect timing needed to intersect Earth makes the likelihood of collision remote. The symbol sizes shown also deceive; each object is many thousands of times as small as Earth.

NASA is concerned none­theless. Scientists estimate that they have found fewer than 1 percent of the projectiles. “We are discovering them at a rapid clip, but the population is very large,” says Donald K. Yeomans, manager of the Near Earth Object Program Office at NASA’s Jet Propulsion Laboratory. A NASA advisory group says that for $250 million to $300 million annually over 10 years, the space agency could inventory the objects and develop and test technologies that could alter a worrisome asteroid’s trajectory. One option: ram it with a massive space­craft to knock it off course. —Mark Fischetti

Mark Fischetti was a senior editor at Scientific American for nearly 20 years and covered sustainability issues, including climate, environment, energy, and more. He assigned and edited feature articles and news by journalists and scientists and also wrote in those formats. He was founding managing editor of two spin-off magazines: Scientific American Mind and Scientific American Earth 3.0. His 2001 article “Drowning New Orleans” predicted the widespread disaster that a storm like Hurricane Katrina would impose on the city. Fischetti has written as a freelancer for the New York Times, Sports Illustrated, Smithsonian and many other outlets. He co-authored the book Weaving the Web with Tim Berners-Lee, inventor of the World Wide Web, which tells the real story of how the Web was created. He also co-authored The New Killer Diseases with microbiologist Elinor Levy. Fischetti has a physics degree and has twice served as Attaway Fellow in Civic Culture at Centenary College of Louisiana, which awarded him an honorary doctorate. In 2021 he received the American Geophysical Union’s Robert C. Cowen Award for Sustained Achievement in Science Journalism. He has appeared on NBC’s Meet the Press, CNN, the History Channel, NPR News and many radio stations.

More by Mark Fischetti
Scientific American Magazine Vol 304 Issue 3This article was published with the title “Death by Asteroid: A Graphic Look at Rocky Threats from Space” in Scientific American Magazine Vol. 304 No. 3 ()
doi:10.1038/scientificamerican032011-omc872Q5vwTxAisF3WJrp

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