Wednesday, March 11, 2009
Prepare for destruction from space
From the RoundTable blog
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Rob Montz
Montz is a writer based in Washington, D.C.
On Feb. 2, an asteroid the size of a 10-story building zoomed past Earth at an unusually close distance. Moving at 12 miles a second, asteroid 2009 DD45 came within 49,000 miles of our planet, or about double the distance of the farthest orbiting satellites. "Celestially speaking," said NASA's Don Yeoman, "the rock was quite close."
Most people are inclined to see this news as nothing more than a fun fact to bring up at a party. The possibility of an actual cosmic collision is so remote that it's not worth serious attention, right? And even if it's not so remote, there's nothing we can do about asteroids anyway, so why sweat it?
Wrong on both counts. As the Jet Propulsion Laboratory's Steven Ostro puts it, "Suppose that there was a button you could push and you could light up all the Earth-crossing asteroids larger than about 10 meters; there would be over 100 million of these objects in the sky ... all of which are capable of colliding with Earth."
Worries about near-earth objects, NEOs as they're officially known, aren't confined to kooks who have watched one too many disaster movies. Interstellar material does occasionally hit the Earth, and the effects are as devastating as you'd expect.
In 1908, an asteroid about the size of the one that just missed us entered that Earth's atmosphere and exploded over Siberia. The force was 1,000 times more powerful than the nuclear bombs used during World War II and cleared more than 800 square miles of forest area.
Of course, our planet has seen worse. Sixty five million years ago, a six-mile-wide asteroid crashed into the southeastern coast of Mexico. It was traveling 200 times the speed of sound, burning hotter than the surface of the sun, and caused an explosion more powerful than 300 million nuclear bombs. The resulting debris blotted out the sun, choking off plant life and causing the extinction of more than 70 percent of Earth's species, including dinosaurs.
There are concrete steps we could take right now to avoid, or at least contain the damage from, a NEO impact in the future. These steps require a relatively small investment, have the potential for a massive payoff, and double as safeguards against other events that threaten humanity.
Yet the U.S. government is mostly apathetic about the issue.
"The fact that we haven't even formulated what our reaction would be to a potential threat from space is disturbing, considering the magnitude of the risk involved. You'd think there would be a plan ready, but there isn't," Rep. Dana Rohrbacher said. He has been been pushing to increase NASA resources for NEO research.
Four years ago, NASA was instructed by Congress to catalog 90 percent of potentially threatening NEOs, and develop measures to divert them. The agency has barely spent a dime on the project.
The National Science Foundation plans to totally defund the Arecibo radio telescope, one of the world's best detectors of NEOs, by 2010. The total number of Americans actively searching for NEOs probably couldn't staff a Starbucks.
NASA should finish its NEO catalog and fully investigate deflection techniques, such as running manned missions to dangerous NEOs. There also needs to be serious research into the feasibility of establishing human colonies on other planets. And NASA should have at the ready spacecraft capable of getting to the moon -- currently it doesn't have any and the blueprints for the last rocket that could get that far have been destroyed.
Could these efforts be in anticipation of an event that might not occur for another million years? Possibly.
But the enormity of the cost of being unprepared -- the partial or total annihilation of the human race -- justifies the expense.
What's more, most measures against a cosmic collision are equally useful against the other serious threats to our long-term survival on this planet.
Nuclear wars, super viruses, global warming -- humanity keeps inventing ways to obliterate itself. Who knows what we'll add to that list a decade from now. Shouldn't we have a Plan B or, for that matter, a Planet B?
No less of an authority than Stephen Hawking has said as much. At a NASA conference last April, he called for a concerted effort to establish colonies on Mars and the Moon. "If the human race is to continue for another million years, we will have to boldly go where no one has gone before," he said.
Preparing to go where we haven't gone before is going to take awhile. We should start now.
