The bad news: A million other potentially dangerous — and unknown — city-killing space rocks are out there, and one of them could be on a collision course with Earth. Critics say NASA and other space agencies are not doing enough to scan for these threats.
“It’s like Mother Nature sending a warning shot across our bow,” said Don Yeomans, who tracks meteors for the Jet Propulsion Laboratory in Pasadena, Calif.
The Air Force, meanwhile, is leaving the tracking to NASA.
An astronomer in Spain discovered the meteor a year ago.
NASA-funded scientists then ran the numbers: The meteor was about 150 feet wide.
It cruises around the sun in an orbit almost identical to Earth’s. Our year is 365 days. Its year is a day longer. Like a drunk driver weaving across lanes, meteor 2012 DA14 crosses paths with Earth twice a year, at varying distances.
Despite these opportunities for disaster, scientists tracking the asteroid are confident 2012 DA14 won’t collide with us for at least the next century, which is as far as they’ve been able to project its path.
NASA began rigorously scanning the sky for cosmic hazards only in 1998, when Congress told it to. Agency scientists said Thursday they are confident their network of ground and space telescopes have found at least 95 percent of potentially planet-killing asteroids, those a half-mile wide or more. None of these monsters is headed toward Earth, Yeomans said.
But the agency has done much worse identifying smaller threats, said Ed Lu, a former NASA astronaut. Lu spearheads the B612 Foundation, which last year began raising private funds to build an asteroid-spotting space telescope.
“Saying we’re only going to find the civilization-killers is a [sub-par] threshold,” Lu said. “We can do better than that.”
Lu said that so far the human race has spotted only about 1 percent of the smaller, but still dangerous, asteroids near Earth.
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