Oh Crap, an Asteroid

If the sky is falling, chances are pretty good that Dr. Timothy Spahr will be among the first to know.
By Timothy J. Mcginn

If the sky is falling, chances are pretty good that Dr. Timothy Spahr will be among the first to know.

In a sparsely decorated office tucked deep inside the Harvard-Smithsonian Center for Astrophysics, Spahr sifts through global reports of significant debris in the heavens and attempts to pinpoint long-term threats to Earth’s viability.

“If I want a weekend off, that’s kind of crappy,” says the surprisingly laid-back Spahr, who has been an avid astronomer since spying a comet at the age of five. “Only two of us [in the world] are tasked specifically with dealing with near-Earth asteroids.”

After separating the false alarms from the potential catastrophes, Spahr forwards his calculations to NASA’s Jet Propulsion Laboratory (JPL) for final trajectory projections before heading home to sneak in an hour of bird watching before dusk. Planetary demise three decades away isn’t worth losing sleep over.

But the imminent strike of an asteroid 100 feet in diameter, slamming into the atmosphere with enough force to generate the effects of a nuclear weapon? Well, just maybe.

On Jan. 13, Spahr posted a few promising asteroid locations on the Minor Planet Center website, before heading to dinner with a friend. But while he enjoyed his “only-once-a-year” night on the town, the alarms began to sound worldwide. An amateur astronomer forecast that one of Spahr’s potentials was rapidly approaching the sky somewhere over the Northern Hemisphere. Based on the information available, a 25 percent chance of a collision within days was quickly confirmed.

“I’ve never seen anything that’s gone over a percent after talking to our JPL guy,” Spahr said. “When I get something that looks fun, I send it to him immediately and he comes back with a number. One in 32 million or something. Nobody cares then.”

In response, Spahr quickly approximated a window through which the asteroid would have to travel in order to remain a threat. However, the skies remained clear during that window, and Earth was safe for yet another day.

“We never really looked for the ones next week,” Spahr said, “because all the work that we had done had suggested it would be very rare for us to find one right before it hit.”

Just to ensure that the possibility could be ruled out completely, Spahr and his associates quickly developed a program to track short-range threats as well. However, he basically rules out the chance of any threatening body approaching Earth undetected.

Still, those efforts haven’t stopped Hollywood moguls from churning out asteroid-themed blockbusters. “I went and watched Deep Impact, but I didn’t watch Armageddon,” said Spahr. “For Armageddon, I helped them do a promo, and we tried to tell them that it was pretty dumb. A Texas-sized asteroid was going to hit in what, two weeks? That would be as bright as Jupiter in the sky. You would go outside and go, ‘Oh crap, an asteroid.’”

Four words that, thanks to Spahr, will probably never be uttered.

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