Mark Drajem, ©2013 Bloomberg News

March 19 (Bloomberg) -- A catastrophic meteor strike that would trigger the kind of destruction blamed for wiping out dinosaurs millions of years ago is unlikely in the next several centuries, the U.S. space agency administrator said.

“We are making marked progress in assessing the risk to our planet from smaller objects that could produce regional disasters,” Charles Bolden, the NASA administrator, said today in testifying to the House Science Committee. Still, “smaller objects, such as the recent impact in Russia will always be difficult to detect and provide adequate warning.”

A meteor blast over Russia last month put fresh focus on efforts to launch a spacecraft into a distant asteroid in a bid to prove that incoming objects from space can be knocked off a collision course with Earth.

Defending the planet against asteroids, a focus of former astronauts, astronomers and amateur hobbyists, generated worldwide discussions this year as the largest meteor to explode near Earth in a century blew out windows and injured 1,200 people in the central Russian town of Chelyabinsk near the border with Kazakhstan.

The blast in the remote Chelyabinsk region was the largest recorded since 1908, when a meteroite flattened more than 800 square miles (2,100 square kilometers) of Siberian forest.

A space object, if it’s big enough and hits in the right spot, could destroy a city or worse. Scientists blame an asteroid more than 6 miles in diameter for wiping out the dinosaurs 66 million years ago.

Source: http://www.sfgate.com/business/bloomberg/article/NASA-Says-Catastrophic-Asteroid-Hit-Unlikely-for-4366757.php

To contact the reporter on this story: Mark Drajem in Washington at mdrajem@bloomberg.net