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'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.
"It won't just destroy a country, it would destroy a continent and have global implications for our climate," Opik, who is campaigning for a program to prevent giant asteroid strikes, said.
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.