London, March 16 (IANS) Preparing itself to deal with a potential asteroid impact, NASA has drawn up plans to build a huge nuclear spacecraft that is capable of shunting or blowing up dangerous space rocks and safeguarding life on Earth.

The spacecraft named Hammer (Hypervelocity Asteroid Mitigation Mission for Emergency Response) is an eight tonne spaceship which could deflect a giant space rock, if it happens to hit Earth, The Telegraph reported late Thursday.

The 1,600-foot-wide asteroid Bennu is circling the sun at 63,000 mph. It is now at a comfortable 54 million miles from Earth.

While NASA's Osiris-Rex mission is en route to Bennu to take samples, in a new paper detailed in the journal Acta Astronautica, experts calculated the time and payload it would take to move or destroy asteroid Bennu, that is been monitored since its discovery in 1999.

Although there is little risk it could hit the Earth, it is still considered as an NEO, or Near Earth Object, which would hit the planet with 1,450 megatons of TNT, the report said.

Bennu's impact would release "three times more energy than all nuclear weapons detonated throughout history", said Dante Lauretta, professor at the University of Arizona.

"The impact would release energy equivalent to 1,450 megatons of TNT," Lauretta said.

However the study showed that Earth would need years of warning to be able to put a deterrent plan in action.

The experts calculate that 7.4 years would be needed from building Hammer, to the craft hitting the asteroid.

Earth is hit by asteroids with surprising regularity but most are too small to do much damage or fall in unpopulated areas.

NASA's Centre for Near-Earth Object Studies now lists 73 asteroids which have a one in 1,600 chance of hitting the Earth, the Telegraph said.

--IANS

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