WASHINGTON (CN) - What would the United States do if astronomers identified a "city destroyer" asteroid on a collision course with New York City? "Pray," NASA official Charles Bolden told the House Committee on Science, Space and Technology.
Dr. John Holdren, President Obama's director of the Office of Science and Technology Policy, testified that the prospect of a massive space rock bashing into Earth is a "once in a thousand years event." But the recent explosion of a 20-meter asteroid over Russia and the close flyby - just over 17,000 miles above the Earth's surface - of an asteroid the size of the White House prompted Congress to address the detection and mitigation of Near Earth Objects at the Tuesday hearing.
"A good segment of the population thinks we can just call Bruce Willis," said Rep. Bill Posey, R-Fla.
But Bolden, Holdren and U.S. Air Force Space Commander Gen. William Shelton outlined a more likely scenario if astronomers can detect large asteroids on a collision course with Earth.
"What you can do in principle, if you have a very powerful laser, is to cause jets of material heated by the laser to fly off of the asteroid, and that is essentially the equivalent of a jet engine pushing the asteroid off course," Holdren said.
Holdren described other approaches to deflecting asteroids, including hitting them with heavy blows and approaching them with robotic probes.
Simply blowing them up could simply change the catastrophe, with fragments of the rock peppering the Earth like buckshot.
Bolden noted the president's plan to send astronauts to land on asteroids by 2025.
Holdren and Gen. Shelton testified that astronomers can detect most large asteroids near Earth through the Air Force's large network of space-born infrared sensors.
But Committee Chairman Lamar Smith, R-Texas, doubted it.
"Until it entered our atmosphere, the Russian meteor went completely undetected," Smith said. "On the same day a larger asteroid discovered by amateur astronomers and tracked closely by NASA passed safely by the Earth, but within the orbital belt of weather satellites."
Holdren said the Earth gets smacked frequently by meteorites, taking hits from basketball-sized rocks daily and car-sized rocks weekly.
Asteroids are rocky objects in space. When burn in the Earth's atmosphere, they are called meteors, or shooting stars. Space rocks that hit the Earth are called meteorites.
"Who monitors this screening for all these objects?" asked Rep. Randy Weber, R-Texas. "Does it ding your iPhone when it's coming?"
Utah Republican Chris Stewart asked Holdren how the government would notify the public if a large asteroid were headed toward the country.
Holdren said the White House would call the necessary officials to the Situation Room and a course of action would be determined. He said he believed the government would tell the public.
He said the Earth is only 30 percent land and just 2 or 3 percent of the land is urban, so it's unlikely that a large meteor - which he called a city destroyer - would strike an American city.
With the effects of sequestration cuts looming, representatives on both sides of the aisle were concerned about the costs of increased efforts to detect and deflect asteroids.
"This is a global problem," Bolden said. "Cooperating with China is the elephant in the room. This Congress doesn't want us to cooperate with China."
Holdren said U.N. representatives met in February to discuss a global effort to deal with asteroids, but most members of the committee expressed skepticism about other countries bearing any costs of asteroid mitigation.
Sequestration cuts could pose a problem, said Rep. Eric Swalwell, D-Calif. Two nuclear labs in his district are set to furlough employees on Fridays.
"Is there a way that we can guarantee that one of these Near Earth Objects does not hit on a Friday?" Swalwell asked.
Gen. Shelton, whose system of space surveillance sensors tracks 23,000 objects in space, some as small as a softball, said the money he has to cut from his department will affect the country's ability not only to track asteroids orbiting the sun, but also missiles.
He said the government should be spending $200 million to $300 million a year detecting and tracking space objects.
Bolden said the president's plan to send astronauts to a meteor will cost billions.
The two-hour hearing was delayed by 10 days due to inclement weather. It will be followed by another hearing on asteroids in April.
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