WASHINGTON (TIP): Nasa has discovered the 10,000th near-Earth object (NEO) that could pass close to our planet in the future. The 10,000th near-Earth object, asteroid 2013 MZ5, was first detected on the night of June 18, 2013, using Pan-Starrs-1 telescope in Hawaii, located on the 3,000-meter summit of the Haleakala crater.

Ninety-eight per cent of all near- Earth objects discovered were first detected by Nasa-supported surveys, the US space agency claimed. “Finding 10,000 near-Earth objects is a significant milestone,” said Lindley Johnson, programme executive for Nasa’s near-Earth Object Observations Programme at Nasa Headquarters, Washington. “But there are at least 10 times that many more to be found before we can be assured we will have found any and all that could impact and do significant harm to the citizens of Earth,” Johnson said.

Near-Earth objects (NEOs) are asteroids and comets that can approach the Earth’s orbital distance to within about 45 million kilometres. They range in size from as small as a few feet to as large as 41 kilometres for the largest near-Earth asteroid, 1036 Ganymed. Asteroid 2013 MZ5 is approximately 300 meters across.

Its orbit is well understood and will not approach close enough to Earth to be considered potentially hazardous. “The first near-Earth object was discovered in 1898,” said Don Yeomans, long-time manager of Nasa’s near-Earth Object Program Office at the Jet Propulsion Laboratory in Pasadena. Of the 10,000 discoveries, roughly 10 per cent are larger than six-tenths of one kilometre in size – roughly the size that could produce global consequences should one impact the Earth. However, the Nasa’s NEOO programme has found that none of these larger NEOs currently pose an impact threat and probably only a few dozen more of these large NEOs remain undiscovered.

The vast majority of NEOs are smaller than one kilometre, with the number of objects of a particular size increasing as their sizes decrease, Nasa said. A NEO hitting Earth would need to be about 30 meters or larger to cause significant devastation in populated areas. Almost 30 per cent of the 460- foot-sized NEOs have been found, but less than one per cent of the 100-footsized NEOs have been detected