DECRYPTION – NASA has struck and deflected an asteroid for the first time. Measuring 160 meters in diameter, this object highlights the danger that these smaller projectiles can represent for the Earth.
On February 15, 2013, at 9:20 a.m., a bolide exploded in the sky above the city of Chelyabinsk, in the Russian Urals. The shock wave shatters windows for miles around, and thousands of people, drawn to their windows by the excess brightness in the sky that preceded the explosion, are injured. It is now estimated that the power of the explosion was equivalent to 500 kilotons of TNT, or about 30 times that of the bomb dropped on Hiroshima in 1945.
“The object that exploded over Chelyabinsk was small, it was 20 meters in diameter, and no one saw it coming, because it was coming from the direction of the Sun, an area of the sky where telescopes cannot observe”explains Jérémie Vaubaillon, astronomer at the Paris Observatory and specialist in the trajectories of small bodies in the solar system.
The probabilities of a large impact
The event surprises everyone, and reminds us that the danger of asteroids for our planet is not limited to giant objects, over 1 kilometer…