Washington: US scientists have calculated that an asteroid headed for Earth in 2880 could - if it collides - trigger massive "tsunami" waves that would drown many coastal areas.

Known as 1950DA, the asteroid was first discovered 53 years ago and is the only one - of the many thousands discovered so far - which astronomers have been unable to dismiss as a threat to Earth. According to recent calculations, it could collide with Earth on Saturday, 16 March 2880.

According to a report in 'News in Science', in an effort to conduct a realistic assessment of the impact hazard, Dr Steven Ward and Dr Erik Asphaug of the University of California at Santa Cruz conducted a detailed computer simulation of the impact of 1950DA.

Their results appear in the June issue of the 'Geophysical Journal International'. The 107-metre-wide asteroid is likely to strike the oceans, which represent 70 per cent of Earth's surface. A collision in the Atlantic would generate waves up to 122 metres high that would sweep the East coast of the USA and the Western coasts of Portugal, France, Britain and Ireland, says the report.

"From a geologic perspective, events like this have happened many times in the past," Ward said. "Asteroids the size of 1950DA have probably struck the Earth about 600 times since the age of the dinosaurs."

Based on the assumption that the asteroid would strike the Atlantic at 61,000 km/h, Ward and Asphaug predict that it will blow a hole all the way down to the seabed and 18 km across. As water rushes back into the hole, the impact would create tsunamis which would spread across the Atlantic and the Caribbean.

ANI