Posted on 07/24/2002 6:37:46 AM PDT by 6ppc
LONDON (Reuters) - A massive asteroid could hit Earth in just 17 years' time, destroying life as we know it, a British space expert said Wednesday.
The asteroid -- the most threatening object ever detected in space -- is 1.2 miles 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 told Reuters.
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 cataloged, but the scale in terms of the threat keeps changing," said Peter Bond, spokesman 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 program.
Since then, Peiser said scientists at the U.S. National Aeronautics and Space Administration's (NASA ( news - web sites)) 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.
LONDON (AP) - Astronomers are carefully monitoring a newly discovered 1.2-mile-wide asteroid to determine whether it is on a collision course with Earth.
Initial calculations indicate there is a chance the asteroid — known as 2002 NT7 — will hit the Earth on Feb. 1, 2019. But scientists said Wednesday that the calculations are preliminary and the risk to the planet is low.
"The threat is very minimal," Donald Yeomans, of NASA ( news - web sites)'s Jet Propulsion Laboratory in Pasadena, Calif., told British Broadcasting Corp. radio. "An object of this size would be expected to hit the Earth every few million years, and as we get additional data I think this threat will go away."
The object was detected on July 9 by the Lincoln Near Earth Asteroid Research Project in New Mexico. It orbits the sun every 837 days, and NASA scientists predict its path could intersect Earth's orbit. But they say more observations over the coming months will help them plot its course more accurately.
NASA's Near Earth Object program gives the asteroid a rating of "1" on the Torino impact hazard scale — within a range of "events meriting careful monitoring," but not concern.
However, the discovery has provided more ammunition for those who say humans should take the risk posed by space objects more seriously.
"There's a good chance this particular object won't hit us, but we know that a large object will hit us sooner or later," said British lawmaker Lembit Opik, who has long warned of the danger posed by asteroids.
NASA estimates that asteroids big enough to cause catastrophic destruction could theoretically hit Earth every million years, or at longer intervals.
Last month an asteroid the size of a soccer field missed the Earth by 75,000 miles — less than one-third of the distance to the moon in one of the closest known approaches by objects of its size. Scientists said if it had hit a populated area, it would have released as much energy as a large nuclear weapon.
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On the Net:
NASA's 2002 NT7 impact risk: http://neo.jpl.nasa.gov/risk/2002nt7.html
I'm sure the dems would blame it as a right wing conspiracy
LOL. I picture Kennedy and Leahy right off the bat because they qualify under both headings: dinosaurs and Democrats.
I think that only one months time is very quick to come to such a conclusion.... But then so does he...
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.
Yet he could not restrain himself from publishing this titillating observation, for in a month or so there would be no news at all and no one would have ever hear the name of Dr. Benny Peiser.
Could an asteroid be deflected?
By Ivan Noble
BBC News Online science staff
It will take weeks or even months before astronomers will be able to confirm their suspicion that asteroid 2002 NT7 will pass very close to but not hit the Earth early in 2019.
We'll probably find that what is currently a possible hit will become a near miss
Mark Bailey
Armagh Observatory
"As further observations accrue, we'll probably find that what is currently a possible hit will become a near miss," Professor Mark Bailey, director of the Armagh Observatory in Northern Ireland, told BBC News Online.
In the very unlikely event that 2002 NT7 did turn out to be on a direct collision course, astronomers would have plenty of time to make accurate predictions about the time and location of the impact, and, with luck, to come up with a plan to deflect it.
"It's not like dealing with space debris, where the object may be irregularly shaped and tumbling and where even hours before impact you don't know exactly when and where it's going to come down," said Professor Bailey.
"With an asteroid impact, it's more like when Shoemaker-Levy 9 hit Jupiter.
"There we were able to calculate the exact time of impact almost to the second," he said.
Asteroid rendezvous
In the most unlikely event that it were on collision course, there would be no more important project than to try to deflect it, he added.
"It orbits roughly every 2.2 years, so there would be several opportunities to rendezvous with it.
"There'd be opportunity to assess what it's made of, find out whether it's made of rock and ice, or iron, whether it's a rubble pile or a solid body.
"It would make sense to put a beacon on it so that you'd then have a very precise knowledge of its orbit," Professor Bailey said.
No-one has yet seriously tried to come up with a plan to deflect an incoming asteroid, but given years of warning and an asteroid which orbits relatively frequently, giving it a small nudge early on might do the trick.
"Relatively benign deviations imparted years ahead are magnified each time the asteroid goes around the Sun and would hopefully be enough to turn a projected impact into a near miss.
Solar option
"One could even imagine landing on it and firing a rocket engine.
"People have talked about some kind of a mass driver, where pieces of rock would somehow be broken off the asteroid and cast off into space.
"Even a solar sail might be a possibility," Professor Bailey told BBC News Online.
Such a device might catch the solar wind - a constant stream of particles emanating from the Sun - and use the small but significant energy they carry to cause a tiny deflection in the asteroid's path.
And the last one hit, what, one or two million years ago?
"Hello! McFly! [knock-knock-knock]"
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