Asteroid impact on the earth is always a major problem for human beings. 65 million years have passed since the last destruction of life. On the time line, the next asteroid impact on the earth is bound to happen. This is just a matter of time. At present, there are thousands of asteroids that can threaten the earth, and many of them can not be observed in the dark.
Almost all the major planets in the solar system have been hit by asteroids of different degrees. The earth is lucky. The moon, the moon’s satellite, is covered with craters of various sizes. We can see how hard the moon was hit.
According to scientists’ conjecture, Mars used to be a beautiful and rich planet, just like the earth. The Martian civilization lived very well. Suddenly one day, an asteroid flew to Mars, causing a sudden change in the Martian climate and the disappearance of the Martian civilization.
Since the earth was formed billions of years ago, asteroid impacts have also occurred. The mattero crater in Arizona, USA, was formed 49 000 years ago by an asteroid with a diameter of only 50 meters. The diameter of the entire crater is 1.6 km. Experts say that although the crater is only 1.6 kilometers in diameter, if an asteroid of this size hits the earth now, its impact will destroy a super large city.
You must have heard of the Tunguska explosion. On June 30, 1908, an asteroid exploded over the Tunguska region of Russia, destroying about 1500 square kilometers of forests and villages. According to scientists, this is an asteroid with a speed of more than 100000 kilometers per hour, which exploded and disintegrated about 18 miles from the ground, producing energy equivalent to 185 Hiroshima atomic bombs.
In January this year, an asteroid with a size and mass close to a 10 story reinforced concrete building passed the earth at close range. The closest distance is half of the distance between the earth and the moon. The most terrible thing is that for this asteroid, it was only discovered seven days before it was found!
It can be seen that the threat of asteroids is everywhere. At present, human beings are not prepared to prevent the threat from the sky. If there is an asteroid coming straight to the earth, human beings can do nothing.
Some friends say that it is possible to launch a nuclear bomb to bomb an asteroid. This is an idea put forward by some scientists, but in fact it is very difficult to implement it. Some asteroids are very dense, like steel, and the nuclear bomb can’t break them up. Even if it can explode, it will split an asteroid into several small meteorites, which can’t remove the threat to the earth. The most effective way is to try to change the orbit of the asteroid and let it pass the earth.
Not long ago, NASA successfully changed its orbit by crashing a man-made aircraft into a small meteorite, which is also a practical way to solve the Asteroid Threat in the future. However, it is not so easy to really change the orbit of a relatively large asteroid. It still needs continuous efforts and progress in science and technology.