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Prepare Earth for more asteroid strikes, say scientists

A new study suggests we should expect an asteroid strike every decade or two. And one scientist warns that the last asteroid to pass by us wasn't even noticed until it had gone.

2 min read
How one Russian driver saw the new arrival at Chelyabinsk. Screenshot by Eric Mack/CNET

We've become so used to change that stability seems like a quaint novelty.

So we'll no doubt find it quaint to discover that things might be falling on us from the sky with additional regularity over the next 100 years.

You might have only just got over the news that an asteroid might -- just might -- hit us in 2032.

But now, as The New York Times reports, scientists believe we should get used to the idea that asteroids might hit us every decade or two.

It points to two research papers published in Nature, in which a group of scientists wonder about the future.

Both papers were stimulated by the asteroid that struck Chelyabinsk in Russia earlier this year.

It seems that current warning systems focus on asteroids that are at least 1 kilometer wide.

However, Edward Lu, a former NASA space shuttle astronaut who now is launching a private endeavor called B612 to spot the slightly smaller asteroids, believes radical plans and better telescopes are needed.

He told the Times: "One kilometer is end-of-human-civilization kind of dangerous."

The last asteroid to come near us (and the one that may come by again in 2032), TV 135, was significant because of a small detail.

As Professor Peter Garnavich of the University of Notre Dame told me in an e-mail: "The asteroid 2013 TV135 did not come very close to the Earth in September. Its closest approach was more than 4,000,000 miles away. What is interesting about this asteroid is that it was not discovered until after it passed by, meaning this would have been a big surprise had it been on a slightly different orbit."

We've had enough big surprises lately, so this shows the need for better scientific vigilance.

There are those prepared to step up and do their part to defend us. Neil DeGrasse Tyson, for example.

B612 contends that this isn't going to be easy. A statement on its Web site might cause a chill or two: "There are about a million near-Earth asteroids that are large enough to substantially damage or destroy a major city."

The thing is that nations need to work together to help defend us. Some will fear there's a million-to-one chance of that.