WASHINGTON - Agence France-Presse
The nearest approach of asteroid 2012 DA14 to Earth is shown in this NASA handout still frame from an animated video. REUTERS photo
NASA, universities and private groups in the U.S. are working on asteroid warning systems that can detect objects from space like the one that struck Russia
last week with a blinding flash and a mighty boom. But the U.S. space agency reiterated that events like the one in the Urals, which shattered windows and injured nearly 1,000 people, are rare.
“We would expect an event of this magnitude to occur once every 100 years on average,” said Paul Chodas of NASA’s Near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena, California.
NASA estimates that before entering the Earth’s atmosphere above Russia, the asteroid measured 17 meters in diameter and weighed 10 tons. Fragments of the asteroid caused an explosion equivalent to 500,000 tons of TNT when they hit.
The same day, a 45-meter in diameter asteroid known as 2012 14 whizzed harmlessly past the Earth, its passage overshadowed by the bright arc drawn across the Russian
sky that same day. But had it hit ground, 2012 DA14 could have obliterated a large city.
Ten years ago, NASA
would not have been able to detect 2012 DA14, said Lindsey Johnson, near earth object (NEO) project manager at NASA
said recently. But he said NASA
has made progress on learning how to detect small asteroids.
Johnson said there are many of these objects flying around near the Earth say half a million, and they are hard to track because of their small size.