We can do nothing except Evacuating that place if a large Astroid around 140 mtr size detected today and if it's going to it hit a Earth city after next three month.
We have to make some good underground bunkers in many places around the world for our safety.
According To NASA scientist if we detect a Astroid 10 years before then only we can shift the orbit of that Astroid or we can destroy it with nuclear bomb. We have to do this task before three years of its collision date with Earth.
This chart shows that size of Astroid and its cause of impact on Earth.
Magnitude of Destruction in Earth by Astroid depends upon size and velocities of that Astroid.
According To Scientist a 150 mtr Astroid have energy of 288 megaton which is six times higher than largest nuclear bomb energy in the eath.
According To research there were 16000 Astroid present near Earth orbit nearly at a distance of 28 Million miles away.
Around two million Astroid present between Mars and Jupiter.
Nasa only detects 1600 Astroid orbital data those near the Earth. Nasa predict that there is no chance of great Astroid collision next 100 Years.
But nasa observe 2000 Astroid which are 4647790 miles away from the Earth by its tracking system.
Near Earth Objects Wide Field Infrared Survey Explorer is the main telescope that Nasa used to detect an Astroid.
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Source: https://www.vox.com/a/asteroid-day