The 5th mass extinction, where 75% of life on Earth, including dinosaurs, disappeared at the end of the Cretaceous Period of the Mesozoic Period 66 million years ago is also known to have been caused by an asteroid collision. The Chicxulub crater is 180 km wide and 20 km deep on the Yucatan Peninsula in Mexico. This crater is believed to have been formed when an asteroid collided with the Earth. An element called iridium, which is contained in many asteroid fragments, is a rare element in the earth’s strata, but it was found in extremely large quantities in strata formed at the end of the Cretaceous period. It is strong evidence that there was a collision between an asteroid and the Earth at that time.
The largest asteroid impact in history was the Tunguska explosion of 1908. More recently, in March 2013, a huge meteorite exploded 30 km above Russia, destroying 7,000 buildings and injuring 1,400 people. The impact of the explosion at that time is said to have reached dozens of times when the power of the atomic bomb was unleashed on Hiroshima.
On September 27th, a groundbreaking step was taken to save mankind from the fear of an asteroid impact that could happen again. The National Aeronautics and Space Administration (NASA) conducted an experiment to change the orbit of an asteroid by crashing a spacecraft into an asteroid. It was an ‘earth protection’ experiment in case there was a risk of an asteroid colliding with the earth.
The DART spacecraft, developed by NASA, flew towards the asteroid Dimorphos near Jupiter, 10.8 million kilometers away from Earth, and collided with it. Dimorphos is a small moon that orbits the planet Didymos. These asteroids are called binary asteroids. A single asteroid makes it difficult to determine exactly how much the trajectory changes even if a spacecraft flies by and collides with it, while a binary asteroid can measure the orbital change more precisely. That is why Dimorphos was chosen as the target among several asteroids.
The dart flew at 22,000 km per hour, more than 10 times the speed of a bullet, and collided head-on with an asteroid that was also moving more than 10 times faster than a bullet. This asteroid impact experiment will be an important starting point to prevent the earth destruction story in the movie from actually happening.
