You are the president of the United States, and you receive the phone call.
“Mr. President,” the person on the other end says, “there is a one-in-three chance that an asteroid more than 500 feet in diameter will strike somewhere in the northern hemisphere six days from now. We cannot be more precise, though we’ll have better information in the next few days.”
You are the president of the United States. What do you do?
Your science adviser tells you that if the rock hits the planet there is a better than even chance that it will come down in the ocean, but that this is not good news–it could create waves which might destroy coastal cities. It would, of course, be a hazard to ships at sea at the time. It would be a disaster the likes of which we have never experienced both in terms of property loss and, absent an unprecedented evacuation, loss of life as well. The long-term effects on the climate would not be easy to predict, but they would likely be greater than those from a major volcanic eruption.
“Can anything be done?” you ask.
“Other than evacuating coastal cities, no. We have no means of altering the course of the asteroid. We have no way of knowing where it will it or, at this point, if it will hit. By the time we know the extent of the threat, it will be too late even to conduct an orderly evacuation.”
The secretary of Homeland Security and the director of the Federal Emergency Management Agency have more bad news: There is no provision, none at all, for such an evacuation, orderly or otherwise. We’re talking moving everyone, from both coasts, far inland. This includes the entire state of Florida and the entire northeastern megalopolis, as well as Los Angeles, San Francisco, Seattle. It can be done in six days, if we begin right now.
“Don’t forget,” someone chimes in, “you might be ordering people to move from their perfectly safe homes into the area where the thing will hit. And it probably won’t hit at all.”
The implications begin to sink in. No matter what happens, the odds are that your political career has just ended. No matter what you do, you will be second-guessed pretty much forever. Maybe the realization is liberating: whatever decision you make will be easier if it is free from political considerations.
What do you do?
It turns out that something not very much unlike this almost happened two months ago. In January there was evidence that for several hours suggested that the Earth had a frighteningly good chance of being hit by a space rock 100 feet in diameter. (For comparison, the meteor that created Meteor Crater in Arizona was about 150-feet across and hit with a force equivalent to a 20-megaton bomb.) Scientists debated whether or not NASA and the White House should be called. As it turned out, astronomers determined within hours that the asteroid did not pose a threat to Earth. No one had to make hard decisions.
This time. But we did not escape; instead, what scientists agree is inevitable was merely postponed.
I had the opportunity to discuss the threat of an asteroid strike with Edward Teller, the atomic scientist, about 15 years ago. Teller was already championing development of a system to launch thermonuclear devices into space to explode near and change the course of space objects headed for Earth. Contrary to the assumption fostered by decades of science-fiction movies, we do not have silos full of rockets that could be pointed at such an object and lit off, solving the problem after a few minutes of tension. Rockets designed to deliver a warhead to another part of our planet are not capable of taking their bombs beyond Earth’s gravity. And their guidance systems are not up to the task, either: Moscow, it was assumed, would sit still. Asteroids don’t. They move around.
Teller thought an anti-asteroid defense was “essential; it would be irresponsible in the extreme for us not to act.” Technology being invented for the Strategic Defense Initiative, he said, could be adapted. We would need to build the appropriate rockets, decide how they would be deployed, and calculate their effect. It would be neither cheap nor easy, but possible, he said, and more than justified by the threat.
Teller’s concerns did receive some publicity. But the New York Times was dismissive, reporting that your likelihood of being killed by an asteroid is greater than your likelihood of your dying in a plane crash. (The statistic, while true, is a little bit misleading. The frequency of asteroid strikes over Earth’s history, combined with the devastation that results, leads to the conclusion that an asteroid hitting once every 50,000 years would kill more people than would have died in plane crashes in that 50,000-year period. Yet people die in plane crashes every year, while the same cannot be said of people getting squashed by asteroids.)
We do try to keep track of heavenly bodies that might make hell of Earth. The Minor Planet Center is to asteroids as the National Hurricane Center is to tropical storms: It looks for them but can’t do anything about them. The MPC issues regular circulars as well as special ones when events warrant.
All of which is very interesting to you, the president, as you try to figure out what course of action to take. Half of the population of the United States lives along the coasts. An attempt to relocate 140 million people in six days would be chaotic. Phrases like “an abundance of caution” ring hollow–the evacuation itself would have all the important characteristics of a huge disaster. The cost of a false alarm would be enormous.
There is only a one-in-three chance that the asteroid will hit Earth at all. The likelihood that it will hit in a place that would produce immediate destruction in the U.S. is even less–let’s say one in five. The choices are a certain disaster if you act, or a 20-percent chance of a far greater loss of life if you don’t. In a few hours, news of the asteroid will be all over television; tomorrow it will be leading every newspaper. You will be expected to say something, to do something. No matter what you do or say, you will instantly be criticized for it.
You are the president of the United States. What do you do? And if you are not the president of the United States, what would you want him to do?
–Dennis E. Powell writes on technopolitical subjects and is at work on the forthcoming Orbital Mechanics: The Space Shuttle and the People Who Made It Fly.