Close encounter by asteroids makes case for scrutiny
Published : 2013-02-17 20:34
Updated : 2013-02-17 20:34
The twin punch of a meteor raining destruction on remote Russia and an asteroid hurtling past Earth prompted calls from scientists and political leaders for greater vigilance to combat risks from the heavens.
The meteor exploded Thursday over Russia’s Chelyabinsk region in the Ural Mountains, causing shock waves that shattered windows over 50 acres and injured 1,200 residents. The meteor struck 16 hours before an asteroid half the size of a U.S. football field flew within 17,200 miles of Earth, the closest such pass of a body that size in a century.
“It appears to be a cosmic coincidence,” Mark Hammergren, an astronomer at Chicago’s Adler Planetarium, said in an interview. “Both of these things are reminding us that we live on a dynamic Earth. There are a lot of things going on in the universe.”
For astronomers, space agencies and officials, that coincidence points to the need to increase vigilance of space objects. While NASA, the European Space Agency and other bodies track the largest asteroids ― and assess their risks ― smaller objects such as the Russian meteorite are largely undetected.
Meteors similar in size to the Russian object, which may have weighed 100 tons, reach Earth’s atmosphere on average every few decades. They usually fall in the ocean, deserts or far from population centers, said Jay Melosh, a professor in the atmospheric sciences department at Purdue University in West Lafayette, Indiana.
“The Russians got very unlucky,” he said.
The biggest risk may be that governments will deem their nation is being attacked by a bomb or a missile, and launch a strike against an imaginary aggressor.
“People need to realize that there are times when the sky will fall on you,” K.T. Ramesh, director of the Johns Hopkins University Extreme Materials Institute, said in an interview. Government retaliation may be “the biggest risk for us. We are able to destroy ourselves very comfortably.”
Asteroid 2012 DA14 at 2:25 p.m. Washington time was within 27,350 kilometers of Earth over Indonesia.
While DA14 didn’t hit the planet, astronauts and interplanetary evangelists say its fly-by ― and the meteor strike in Russia ― serve as evidence that an asteroid may hit Earth one day.
An asteroid the size of DA14 slammed into rural Russia in 1908 and leveled millions of trees over 820 square miles. The asteroid scientists say plowed into Earth about 66 million years ago, wiping out the dinosaurs, was about 6 miles in diameter.