Washington, Oct 11 (IANS): A small asteroid will safely pass by Earth on Thursday at a distance of approximately 42,000 kilometres, just above the orbital altitude of communications satellites, NASA has said.

The fly-by of the asteroid designated 2012 TC4 will give asteroid trackers around the world an opportunity to test their ability to operate as a coordinated international asteroid warning network.

"Asteroid trackers are using this flyby to test the worldwide asteroid detection and tracking network, assessing our capability to work together in response to finding a potential real asteroid-impact threat," said Michael Kelley, Program Scientist and NASA Planetary Defense Coordination Office (PDCO) lead for the TC4 observation campaign.

The asteroid is estimated to be 15 to 30 metres in size, and according to orbit prediction experts, it poses no risk of impact with Earth.

This asteroid was discovered by the Panoramic Survey Telescope and Rapid Response System (Pan-STARRS) on Hawaii back in 2012.

However, 2012 TC4 travelled out of the range of asteroid-tracking telescopes shortly after it was discovered.

Based on the observations they were able to make in 2012, asteroid trackers predicted that it should come back into view in 2017.

Observers with the European Space Agency and the European Southern Observatory were the first to recapture 2012 TC4, in late July 2017, using one of their large 8-meter aperture telescopes.

Since then, observers around the world have been tracking the object as it approaches Earth and reporting their observations to the Minor Planet Center.

No asteroid currently known is predicted to impact Earth for the next 100 years, NASA said.