Numerous recent blogs and web postings are erroneously claiming that an asteroid will impact Earth sometime between September 15 and 28, NASA said.

On one of those dates, as rumours go, there will be an impact - "evidently" near Puerto Rico - causing wanton destruction to the Atlantic and Gulf coasts of the US and Mexico, as well as Central and South America, it said.

"There is no scientific basis - not one shred of evidence - that an asteroid or any other celestial object will impact Earth on those dates," said Paul Chodas, manager of NASA's Near-Earth Object office at the Jet Propulsion Laboratory in Pasadena, California.

In fact, according to NASA's Near-Earth Object Observations Programme, there have been no asteroids or comets observed that would impact Earth anytime in the foreseeable future.

All known Potentially Hazardous Asteroids have less than a 0.01 per cent chance of impacting Earth in the next 100 years, NASA said.

The Near-Earth Object office at JPL is a key group involved with the international collaboration of astronomers and scientists who keep watch on the sky with their telescopes, looking for asteroids that could do harm to our planet and predicting their paths through space for the foreseeable future.

If there were any observations on anything headed our way, the group would know about it, the US space agency said. "If there were any object large enough to do that type of destruction in September, we would have seen something of it by now," Chodas said.

"This isn't the first time a wild, unsubstantiated claim of a celestial object about to impact Earth has been made, and unfortunately, it probably won't be the last. It seems to be a perennial favourite of the World Wide Web," the US space agency said. In 2011 there were rumours about the so-called "doomsday" comet Elenin, which never posed any danger of harming Earth and broke up into a stream of small debris out in space.

Then there were Internet assertions surrounding the end of the Mayan calendar on December 21, 2012, insisting the world would end with a large asteroid impact.

And just this year, asteroids 2004 BL86 and 2014 YB35 were said to be on dangerous near-Earth trajectories, but their flybys of our planet in January and March went without incident. "Again, there is no existing evidence that an asteroid or any other celestial object is on a trajectory that will impact Earth," said Chodas. "In fact, not a single one of the known objects has any credible chance of hitting our planet over the next century," he added.

- PTI