Around 66 million years ago, a giant asteroid reportedly hit the earth in its full fury and resulted in the extinction of dinosaurs. Even though such a global event has not happened since then, several space experts including Dr Iain McDonald and physicist Neil deGrasse Tyson believe that asteroid hits are not confined to the past, and it will happen in the future too.
As fears surrounding an asteroid hit looms up, NASA, the United States space agency is busy tracking near-earth objects (NEO) that could pose a threat to the existence of the earth in the future. On their website, NASA has also talked about the consequences of a possible space rock hit.
Earth prone to doomsday asteroid hit
NASA revealed that space rocks measuring more than 100 meters in diameter used to hit the earth at an average interval of about 10,000 years.
"With an average interval of about 10,000 years, rocky or iron asteroids larger than about 100 meters would be expected to reach the Earth's surface and cause local disasters or produce the tidal waves that can inundate low lying coastal areas. On an average of every several hundred thousand years or so, asteroids larger than a kilometre could cause global disasters," wrote NASA on its website.
The United States space agency also added that such an impact could pull the earth into a state of chaos. The impact debris could spread all over the earth's atmosphere and it will partially block the sun.
"In this case, the impact debris would spread throughout the Earth's atmosphere so that plant life would suffer from acid rain, partial blocking of sunlight, and from the firestorms resulting from heated impact debris raining back down upon the Earth's surface," added NASA.
Will planetary defence weapon protect the earth from doomsday?
In order to protect the earth from a possible catastrophe due to asteroid hit, NASA is busy developing a planetary defence weapon, aimed to nudge the asteroid from its original collision course trajectory.
However, this planetary defence weapon which is basically a giant spacecraft will not work well with giant asteroids. Space experts believe that nuking could be the only possible way to protect the earth from asteroid hits. But nuking an asteroid could result in radioactive rain which could drastically affect the living beings on earth.