If an unknown large meteor or asteroid were on a collision course with Earth, NASA chief Charles Bolden told a US House of Representatives Science Committee hearing Tuesday, then praying is all America or anyone else could do.
Events in Russia last month have reignited concern about the threat civilization on Earth faces from asteroids.
On February 15, a meteoroid estimated to be about 17 meters in diameter exploded over the city of Chelyabinsk in central Russia. The shock waves from the explosion shattered windows and damaged buildings. More than 1,500 people were injured by flying glass and other debris caused by the shockwave.
“We were fortunate that the events of last month were simply an interesting coincidence rather than a catastrophe,” Lamar Smith (R. Texas), the Science Committee chairman, said. Smith called the hearing to find out what is being done and how much money will be needed to better protest the earth in future, Reuters reported.
Later on the same day, a larger, unrelated asteroid, which was discovered last year, passed 27,681km from Earth; closer than the television and weather satellites that surround the planet.
Both events, “serve as evidence that we live in an active solar system with potentially hazardous objects passing through our neighborhood with surprising frequency,” said Eddie Bernice Johnson (D. Texas).
NASA is tracking about 95 per cent of the largest objects flying near Earth, those that are 17,200km (6.2 miles) or larger in diameter.
But only about 10 per cent of an estimated 10,000 asteroids with a diameter of 50 meters (165 feet) or more have been found.
“An asteroid that size, a kilometer or bigger, could plausibly end civilization,” John Holdren, a White House science advisor, told legislators at the hearing.