Earth Vulnerable to Major Asteroid Strike, White House Science Chief Says

DATE: 14/09/2016
SOURCE: SPACE


Strikes such as the Chelyabinsk impact are thought to happen once every hundred years, he added, while Tunguska is regarded as a once-in-1,000-years event.

But, Holdren said, "if we are going to be as capable a civilization as our technology allows, we need to be prepared for even those rare events, because they could do a lot of damage to the Earth."

"This is a hazard that, 65 million years ago, the dinosaurs succumbed to," he added. "We have to be smarter than the dinosaurs."

ARM can help educate us, Holdren said. In late 2021, NASA aims to launch a robotic probe toward a near-Earth asteroid; the current target is a 1,300-foot-wide (400 m) rock called 2008 EV5, but that’s not set in stone, agency officials said.

After it arrives at the asteroid, the spacecraft will pluck a boulder off its surface and then fly along with the space rock for a while, investigating the potential of a deflection strategy known as the "enhanced gravity tractor." (The standard gravity-tractor method calls for nudging a potentially hazardous asteroid off course over the course of years or decades, using the subtle gravitational tug of a tag-along robotic probe; this effect will be "enhanced" by the addition of the boulder's mass.

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