For an anxious world suddenly attuned to the risks from asteroids, a reassuring message is coming from Vienna: Don't worry, earthlings, the United Nations is on the job.
On the same day an asteroid half the size of a U.S. football field passed within an astronomical hair's breadth of Earth, a working group at the UN is wrapping up its 12-year effort on an emergency plan against such threats from space.
"If this asteroid were to hit London, the entire metropolitan area would be gone," Sergio Camacho, head of the effort at the Vienna-based UN Office for Outer Space Affairs, said in an interview.
Camacho's "Action Team on Near-Earth Objects" is set to propose a global asteroid warning network, which would discover, monitor and characterize the risks of those orbiting objects. The group also suggests a team to oversee a space mission to deflect or blow up an asteroid headed for Earth.
Today at 2:25 p.m. New York time, asteroid 2012 DA14 flew within 17,200 miles (27,350 kilometers) of Earth, over Indonesia, the closest recorded approach of an object its size.
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 strike Earth one day. An asteroid of a similar size 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.
Other space objects, such as the meteor that slammed into Russia's Urals region today and caused hundreds of injuries, couldn't be detected with existing telescopes, said Detlef Koschny, a scientist at the European Space Agency who is also part of the UN working group.
"The goal is that we can see objects this size about two days before they hit the Earth," he said today in a telephone interview. Information on those smaller objects should also eventually be part of a UN global database, he said.
In 1998, the U.S. space agency NASA began working on finding and tracking the largest asteroids, typically more than one kilometer in diameter and capable of destroying much of humanity. That's left a big gap in finding smaller objects that would demolish a city while sparing the rest of civilization.
NASA says it has found and mapped 1,310 of the largest, most dangerous "near-Earth objects." The total may account for less than 10 percent of all space threats, it says.
"The whole field needs more resources and funding," Bruce Betts, director of projects at the Pasadena, California-based Planetary Society, founded in 1980 by Carl Sagan to promote space exploration, said in an interview.
In 2008, a group of former astronauts submitted a report to the UN working group, urging a global response to asteroid threats. "Questions arise regarding the authorization and responsibility to act, liability, and financial implications," the Association of Space Explorers wrote in the paper.
In its final report, the UN group proposes an international asteroid warning network to be a clearing house for all observations of near-Earth objects, the technical term for asteroids in close vicinity to the planet.
DA14 was discovered in February 2012 by a group of amateur astronomers at La Sagra Observatory in southern Spain. Jaime Nomen, a dental surgeon who dabbled in astronomy, said his group bought a high-powered telescopic camera and software with the help of a $7,695 grant in 2010 from the Planetary Society.
The probability of an asteroid hitting Earth is fairly low.
"If we're lucky, none of us will see an asteroid coming toward the Earth in our lifetime," Camacho said. "But if we're not lucky and we didn't do anything, the only thing we might be able to do is evacuate."
"This alone could be a disastrous event."
An asteroid on course to hit Earth can be deflected with a spacecraft, redirected with a "gravity tractor" hovering nearby or, as a last resort, targeted with a nuclear explosion.
In the meantime, bureaucracy needs to work at its pace. The UN group's recommendations must be endorsed by the General Assembly, which Camacho expects will consider it when it meets in New York in October.
For some asteroids, there could be 20 to 30 years until the threat becomes imminent, Camacho said. "But we could find one that would give us three months."
Koschny said the asteroid and meteor encounters should help the UN group's cause: "This shows that we are doing something that should be taken seriously. It's not only something a crazy scientist came up with."