Nothing fills movie theaters like the end of the world, which may be why Hollywood keeps turning out apocalypses. Yet most big-screen disaster scenarios pale in comparison to the genuine cataclysm that befell Earth some 66 million years ago, when a 6-mile-wide asteroid slammed into our planet. It left behind a roughly 120-mile-wide crater in the Yucatan and wreaked global environmental havoc. Many scientists believe this was the event that wiped out the dinosaurs and about 80 percent of all animal species. Events of this magnitude are rare, but astronomers assure us something similar will happen again.
Nature provided a little reminder on Feb. 15, 2013. First, a 56-foot-diameter rock exploded without notice above the Siberian city of Chelyabinsk, releasing the energy of more than 30 Hiroshima-size atomic bombs. Later that day, a totally unrelated 150-foot-wide asteroid named 2012 DA14 made a close approach, coming within about 17,000 miles of hitting us — some 5,000 miles closer than many TV and weather satellites.
Astronomers believe millions more large, undiscovered and potentially deadly asteroids lurk out there and could catch us unawares. Testifying before Congress a month after Chelyabinsk and 2012 DA14’s flyby, NASA chief Charles Bolden said that if we had just a few weeks’ notice before an impending asteroid impact, he could offer only one word of advice: “Pray.”
John Remo, a 73-year-old physicist living in New Mexico, finds that remark troubling. For Remo, a scientist at the Harvard-Smithsonian Center for Astrophysics, Bolden’s statement serves as a painful reminder that we, as a country and a world community, have done little to prepare humankind to fend off asteroids bound for Earth, even though it’s within our means to do so. We have the rockets and technical know-how, but have not yet put the pieces together — or mustered the will to do so.
For the past two decades, Remo has devoted himself to rectifying that oversight. In particular, he’s focused on the option of “last resort,” which may, in extreme circumstances, be our first and only resort: using nuclear blasts in outer space to push a menacing asteroid out of harm’s way and onto a benign trajectory. His most recent research has helped quantify the amount of push a nuclear device could deliver in a dire emergency, when no other technology could save us.
