Giant asteroid 'heading close to Earth'
A giant asteroid, weighing 55 million tonnes, is heading close to Earth, say NASA experts.
Robin Scagell of the Society for Popular Astronomy said: "It's rare that we get the chance to see an asteroid up close."If it were to hit the earth, the asteroid, named YU55, would have an impact equivalent to 65,000 atom bombs and would leave a crater more than six miles wide and 2,000ft deep, say the experts.
Passing by at a distance of just 201,000 miles, the asteroid will be the largest object ever to approach the Earth so close.
The US space agency has officially labelled it a Potentially Hazardous Object, but has stressed there is no danger of impact while on its current course.
YU55 orbits the sun every 14 years and astronomers first noticed the asteroid in April 2010 when it was about 1.5 million miles (2.3 million km) from Earth.
There are currently 874 near earth asteroids which are considered to be potentially dangerous. All are monitored and the list is being constantly added to as astronomers discover new objects in near space.Scientists estimate that there is usually one large collision with Earth every few hundred thousand years.