The asteroid that is going to zip past the Earth at nearly 6 million kilometers away tonight is not travelling alone. Nasa scientists tracking the asteroid with the giant Deep Space Network antenna in California have discovered that the asteroid has a small satellite or moon.
The asteroid is about 2.7 kilometers in diameter. The newly found moon that orbits it is just 600 meters wide. Such a ‘binary’ or double system is rare but not unknown to space watchers. About 16 per cent of asteroids with diameters 200 meters or more are binary or even triple systems, a Nasa statement said.