A report was released by The US National Science and Technology Council on Wednesday, on how Earth can be protected from approaching asteroids which impose severe threats for millions. As reported by AP on Wednesday, and as a result of the report, The National near Earth Object Preparedness Strategy and Action Plan, and other strategies are being worked on alongside at the National Aeronautics and Space Administration, with federal emergency agencies, the military, and the White House.
Lindley Johnson, Planetary Defence Officer with NASA, mentioned that scientists have already identified almost 95% of all near to Earth objects with a diameter more significant than a kilometer. The agency was voted down practically over 18,000 such objects of different sizes.
In case, any one of these meteors hits head on a densely populated zone, it could kill millions, as reported on the Wednesday report.
In any case, a stellar object needs not to be significant to cause massive destructions. In 2013, the asteroid which exploded over Chelyabinsk, in Russia was just 66 feet in diameter but produced explosive power similar to that of 500 kilotons of TNT, 26 to 33 times equivalent energy as the nuclear bombs which destroyed Hiroshima and Nagasaki in 1945. Similarly, in 1908, the Tunguska impactor, which leveled almost 770 square miles of the Siberian forest, was only between 220 to 660 feet in diameter and hit Earth with the power as equivalent as 10-15 megatons of TNT, as loud as a few of the most powerful hydrogen bombs built till date.
Longer the notice humans have in advance of any meteors approaching towards Earth, the better it is, said, Johnson. Attempts to deflect it or divert its course requires several years of build and launch of a spacecraft, and more time is needed to intercept its actual path. At least a notice of 10 years is required. The minor time frame can do if the approaching objects possible impact locations can be identified and evacuated in time.
A few of the proposed ways includes positioning a spacecraft nearby to it, to pull it away from its course using gravity, or attaching a spacecraft to it, that would remove it distantly from the impact course or blowing it with a nuclear bomb- The Bruce Willis way solution.
An all-new effort to find out ways to divert incoming asteroids – the DART (Double Asteroid Redirection Test) was announced by NASA last year.
DART is proposed to be NASA’s first mission in the lines of Kinetic Impactor Technique – hitting the asteroids to change its orbit and to defend against its potential future impacts.