Game Over

No matter how you work out the endgame in your head, humans are destined for extinction: Apocalypse is built in to the human condition. Science, which defines and quantifies the heft of that apocalypse, is all about control — in naming the beast, it suggests, we gain power over it. So how do we prevent it? And what does apocalypse actuallymean in a real-world context?

In Los Angeles, partly, it means earthquakes. It means the fear of The Big One that will shake the land until the entire West Coast breaks off like a ?cracker into the ocean. Luckily, in California we have not just one but two motherly, reassuring “Earthquake Lady” scientists to chase the nightmare scenario away. “Southern California will certainly experience more earthquakes similar to the 1857 Fort Tejon and 1906 San Francisco earthquakes,” says Caltech seismologist Kate Hutton. “Those quakes both had magnitudes in the upper 7s, probably 7.8 or 7.9.” If the big quake happens during a Santa Ana wind season, she says, fires are inevitable, and the response will not be as fast as it normally is. If it happens during the rainy season, mudslides will complicate matters. But the biggest problems may come from disruption of the infrastructure: roads, water mains, power lines.

In her office at Caltech, Lucy Jones of the U.S. Geological Survey talks about the possibility of an earthquake causing damage of the magnitude that occurred in New Orleans from Hurricane Katrina. “Oh, yeah,” she says, “we can be a lot worse than that. Our worst-case scenario doesn’t happen very often, but if we put a magnitude 7.5 under downtown L.A., which will happen at some point geologically speaking, you can imagine the damage.” There are 300 faults running through Southern California capable of a magnitude 6. Of those, a hundred run through the Los Angeles metropolitan area. The longest single fault we have, the San Andreas, is capable of producing a magnitude 8. (Northridge was a 6.7.) Earthquakes can even start on one fault and jump to another. The largest quake ever recorded was a 9.5, in Chile.

Jones, whose messy desk looks as if an earthquake has just hit, has run chains of seismometers up and down the Los Angeles River and set off explosions to see the geological structures below. Deaths result from the magnitude of the quake, the proximity of people to it, and the age of the buildings in the area. In Los Angeles, we model what will happen only to the biggest buildings in an earthquake. And we definitely don’t do full-size “shake tables” in L.A., in which an entire building is put on a table that shakes. It costs too much. The Japanese spent $600 million on theirs. “Will the perfect storm happen in my lifetime?” Jones says. “It’s hard to say. I’m getting older, so chances are it won’t. By definition the perfect storm is something that doesn’t happen very often. I’m over 50. I could live another 50 years, but that’s not that long in geologic years.” Given that at some point a big earthquake has to happen, and she’s studied it her whole life, Jones says she’d like to live to see it.

Death comes from above as well as from below. The ancient Mayans, who knew what they were doing sky-wise, kept a long-form calendar based on the movement of the planets. The calendar stops abruptly at the date December 21, 2012, the winter solstice, as if they couldn’t be bothered to track out the remaining days because there would be none. With that in mind, I visit NASA’s Jet Propulsion Laboratory in Pasadena to seek wisdom from Don Yeomans, director of the Near-Earth Object Program, which monitors the comets and asteroids that enter Earth’s neighborhood. It is a sunny September morning — September 11, by coincidence, the anniversary of that day when the end of the world seemed a grave possibility. Yeomans is a tall, smiling, professorial fellow, and I ask him what the probability is that a large asteroid will hit Earth and kill us all.

“Slim to none,” says Yeomans, who has been studying comets and asteroids for more than 40 years. “When you say ‘large’ asteroid, you’re talking about something that’s a mile wide in diameter. Those events don’t occur but every several million years. We get hit by basketball-size asteroids daily. Volkswagen-size asteroids come in twice a year. None of those make it through Earth’s atmosphere. They would have to be half the size of a football field before they can make it through, and you don’t expect those objects but about every 600 to 700 years or so.” Nevertheless, he is keeping an eye on a short list of objects for which he can’t rule out an impact, but only because he hasn’t observed them enough to be able to refine their orbit.

For instance, there’s a big chance (“About 3 percent,” says Yeomans, “which is huge!”) we’ll get hit by the asteroid Apophis, named after the Egyptian god of doom, who lives in the eternally dark underground and tries, nightly, to destroy the sun. Apophis will more likely make a very close approach to Earth — lower than some geosynchronous communications satellites — on April 13, 2029. If it sneaks through a region of space 600 miles across, a “keyhole,” then it will return in seven years to hit Earth. But the chances of that happening are only one in 45,000, and as they refine the asteroid’s orbit, the chances will be even lower. Apophis will simply be visible to the naked eye as a graceful point of light moving across the night sky.