The collision-course space rock is believed to be bigger than the Chebylinsk meteor which exploded above Russia, damaging thousands of buildings and injuring 1,500 people.
NASA earth defence specialists are closely monitoring the close approach of the asteroid known as 2012 TC4.
They are convinced it will not impact, but say it will skim earth at a distance of around 4,200 miles, which is a mere cat’s whisker as astronomical terms.
Asteroid 2012 TC4 is estimated to be between ten and 30 metres (30 and 100 feet) and will pass by earth on October 12.
The 20-metre Chelyabinsk meteor exploded in the atmosphere above the Russian city unexpectedly on February 15 2013.
No space agency had any idea it was approaching before the explosion ripped through the air.
Around 26 to 33 times as much energy as that released from the atomic bomb detonated at Hiroshima was released.
Most injuries sustained were from flying broken glass from buildings damaged by the strength of the explosion.
However, Nasa scientists are aware of the pass of the larger 2012 TC4 and said they were excited about what could be learned from it.
A Nasa spokesman said: “They plan to use its upcoming October close approach to earth as an opportunity not only for science, but to test Nasa’s network of observatories and scientists who work with planetary defence.
“Even though scientists cannot yet predict exactly how close it will approach, they are certain it will come no closer than 4,200 miles (6,800 kilometers) from the surface of earth.”
Michael Kelley, program scientist and NASA Headquarters lead for the TC4 observation campaign, said: “Scientists have always appreciated knowing when an asteroid will make a close approach to and safely pass the earth because they can make preparations to collect data to characterise and learn as much as possible about it.
“This time we are adding in another layer of effort, using this asteroid flyby to test the worldwide asteroid detection and tracking network, assessing our capability to work together in response to finding a potential real asteroid threat.”
Professor Vishnu Reddy of the University of Arizona’s Lunar and Planetary Laboratory in Tucson leads the campaign to reacquire 2012 TC4 and sees it as an opportunity for the collaborative observation campaign to utilize the international aspect of the network.
She said: “This is a team effort that involves more than a dozen observatories, universities and labs across the globe so we can collectively…