Expert warns of asteroid hit
2002-07-24 15:28
London - A massive asteroid could hit Earth in just 17 years' time, destroying life as we know it, a British space expert said on Wednesday.
The asteroid - the most threatening object ever detected in space - is 2km wide and apparently on a direct collision course with Earth.
"Objects of this size only hit the Earth every one or two million years," said Dr Benny Peiser, an asteroid expert at Liverpool John Moore's University in northern England.
"In the worst case scenario, a disaster of this size would be global in its extent, would create a meltdown of our economic and social life, and would reduce us to dark age conditions," he said.
But Peiser and other space experts say they are pretty confident this nightmare scenario will not come about.
"This thing is the highest threat that has been catalogued, but the scale in terms of the threat keeps changing," said Peter Bond, spokesperson for the Royal Astronomical Society.
"If it did hit the Earth it would cause a continental-size explosion... but it is a fairly remote possibility."
The asteroid - named 2002 NT7 - was first detected earlier this month by the United States Linear sky survey programme.
Since then, Peiser said scientists at the US National Aeronautics and Space Administration's (Nasa) near-Earth objects team and at Pisa University in Italy have carried out orbit calculations to work out the probability and potential date of impact to define the risk it poses.
Their calculations show it could hit the earth on February 1, 2019.
"The impact probability is below one in a million, but because the first impact date is so early - only 17 years from now - and the object is very large, it's been rated on the impact risk Palermo Scale as a positive," Peiser said. "It is the first object which has ever hit a positive rating."
Scientists warn, however, that the risk rating has not been reviewed by the International Astronomical Union, which is the main international body responsible for announcing such risks.
Peiser said 2002 NT7 would continue to be monitored by space experts across the world, and that over time, these observations would probably erase the threat posed by it.
"In all likelihood, in a couple of months additional observations will eliminate this object from the list of potential impacts," he said. "I am very confident that additional observations over time will... show that it is actually not on a collision course with Earth."
But he warned that the world should take this as wake-up call and set about preparing for the reality of an asteroid hit in the future.
"Sooner or later - and no one can really tell us which it will be - we will find an object that is on a collision course. That is as certain as Amen in church. And eventually we will have to deflect an object from its collision course," he said.
At the moment, he added, scientists fear it could take at least 30 years for the world to be able to devise and set up a mission to deal with such a threat - a timescale which would be woefully inadequate if the 2019 strike were to happen.