According to the National Aeronautics and Space Administration (NASA) administrator Jim Bridenstine the prospect of a killer asteroid crashing into earths is a distinct possibility in our lifetime. He told this at the 2019 Planetary Defense Conference in Washington.
A tabletop exercise held during the 2019 Planetary Defense Conference in College Park, Maryland. A fictional scenario was prepared by NASA's asteroid experts in which scientists identify an asteroid that seems poised to crash into Earth in 2027. They are also discussing that which region will be affected, how it will pose a risk and how to respond for it. If any such type of situation arises in real life scientists will be ready for it.
It’s a hypothetical that a telescope during the exercise in College Park (US) detects an asteroid between 100 and 300 meters in diameter racing through our Solar System at 14 kilometres per second, 57 million kilometres from Earth.
According to Astronomers a one percent risk is there that the space rock will collide with our planet on 27 April, 2027. It is also said that an asteroid Apophis will hit Earth on 13 April, 2029. What scientists will do then?
Do you know that the countries represented the sixth International Planetary Defense Conference at the University of Maryland's campus in College Park represented China, France, Germany, Israel, Italy, Russia and the United States.
What will happen if an Asteroid hits the Earth? Let us study further.
Any asteroid falling from the sky would have a tremendous amount of energy. For example, according to the scientists, in 2028, the asteroid 1997XF11 will come extremely closer to the Earth but will not hit the planet. If some kind of situation change and asteroid may hits the Earth with a speed of 30,000 mph. Then, it is said that an asteroid travelling at such speed has the energy equal to a 1 million megaton bomb. Is it not strange! It is understood that if an asteroid of this much energy hits the Earth than it will wipe out most of the life on the planet.
Lets us take an example for better understanding.
An asteroid having a size of a house crashed on Earth at 30,000 mph. Then it would have an amount of energy roughly equal to the bomb that fell on Hiroshima may be around 20 kilotons.
This type of an asteroid would flatten reinforced concrete buildings up to half a mile from ground zero and flatten wooden structures perhaps a mile and a half from ground zero. That is, it can do extensive damage to any city.
No doubt if an asteroid is as big as 25 story building then the amount of energy equal to the largest nuclear bombs i.e. 25 to 50 megatons. It would flatten reinforced concrete buildings more than five miles from ground zero. It would completely destroy major cities in the United States.
For more understanding we can say that if a mile wide asteroid were to directly hit New York City, the force of the impact probably flatten every single thing from Washington D.C. to Boston and would cause major damage perhaps 1,000 miles out that is far away as Chicago. Even the amount of dust and debris thrown up into the atmosphere would block out the sun and cause most living things on the planet to perish. If such an asteroid land in the ocean then it would cause massive tidal waves hundreds of feet high that would completely destroy the coastlines.
Do you know when did the last asteroid hit the Earth?
66 million years ago, the last such mass extinction led to the demise of the dinosaurs and coincided with a large meteorite impact; this is the Cretaceous–Paleogene extinction event.
So, we can say that if an asteroid hits the Earth then it will be really a huge loss and will be a very bad day no matter how big it will be. Depends upon the size of the planet, it can also wipe out the life in the planet.