It came without warning: a house-sized asteroid hit Chelyabinsk, Russia, more than a year ago. The asteroid was traveling at nearly 40,000 miles an hour with more explosive energy than the nuclear bomb that exploded over Hiroshima. Those on the ground suffered injuries, mostly cuts, but no one died.
Why? In a word: luck.
"Had it hit much lower, no one who observed the event would have been alive to talk about it," said Dr. Neil deGrasse Tyson, an astrophysicist and the host of "Cosmos" on FOX.
He called that a fortunate experiment, a wake-up call with minimal consequences.
"One of my favorite posters on the Internet says 'asteroids are nature's way of asking you how is that space program coming along?" he said.
Asteroids are rocks, sometimes containing metal, that orbit the sun. When they hit the ground, as the one in Russia did, they're called meteorites.
A meteorite that hit Greenland thousands of years ago weighs about 34 tons. By comparison, the meteorite that hit Russia last year weighed about 10,000 tons.
But hold on. What if there was a way to alter the tracks of asteroids and therefore eliminate the threat they pose to us here on earth?
NASA says there is. The agency calls it the asteroid redirect mission. The Obama administration has asked Congress for $133 million in the 2015 fiscal year to fund it. The goal is to find an asteroid near earth, lasso it, and eventually send humans to land on it and study it.
NASA also wants to prove that it can move an asteroid in case one is on a collision course with us.
"Rather than just run from it and buy water and toilet paper, you can say 'we can deflect this,'" Tyson said.
We asked Dr. Denton Ebel at the Museum of Natural History how that might be done.
"The gravity of our spacecraft would pull the object off its course to a different course," Ebel said. "In the long run, there's an asteroid with our name on it."
Those are ominous words that evoke the thriller "Armageddon."
But scientists say this isn't the stuff of science fiction. It's science fact.
"For the future of our wealth, our health, our security, our energy needs, if we ignore what space has to offer, we will doom ourselves to extinction here on earth," Tyson said.
While Tyson said that he wants NASA to pursue its asteroid ambitions, he acknowledged the technology may still be years away.
A cosmic event doomed the dinosaurs. It might take some big ideas, such as those NASA is studying, for us to avoid the same fate.