The Purple Mountain Observatory of the Chinese Academy of Sciences released the news that the observatory recently discovered a near-Earth asteroid that is flying towards the Earth. This is the first near-Earth asteroid to be discovered globally in 2022, so the continent also became the first country to discover a near-Earth asteroid in 2022.
The first near-Earth asteroid will fly over Earth next month
According to Zhao Haibin, chief scientist of the NEO telescope group, the asteroid was discovered by the NEAR-Earth celestial telescope at about 21:33 on the 1st. It is 43 meters in diameter and about half the size of a standard football field. The minimum orbital rendezvous distance with the Earth is about 341,000 kilometers, which is less than the Earth-Moon distance.
According to international naming conventions, the asteroid is rightfully known as 2022 AA. The first A here represents the discovery time in the first half of January, and the second A represents the first asteroid to be discovered during this time period. That is to say, this asteroid is the first asteroid discovered by humans this year.
Just now, the asteroid is still flying towards us, according to scientists' calculations, it will reach perigee on February 4 and fly 2.55 million kilometers away, the most recent is only 341,000 kilometers, less than the Earth-Moon distance, so there is still a chance that the asteroid will hit the Earth.
The probability of an asteroid hitting Earth
Asteroids orbit the Sun, and when the asteroid is very small, it will be disturbed by the large planet, at which time, the gravitational pull of the large planet will make the asteroid constantly change its trajectory. When an asteroid approaches Earth, it is attracted by Earth's gravity and flies towards Earth.
So an asteroid hitting earth is possible. In fact, under normal circumstances, asteroids will only cross paths with large planets and will not collide. Collisions are only possible when asteroids change speed and direction, and then intersect or coincide with the Earth's orbit.
The probability of an asteroid hitting the Earth is related to its own size, and the smaller the volume, the greater the probability of hitting the Earth. According to the Encyclopædia Britannica, asteroids with a diameter of more than 1 km collide with the Earth every hundred thousand years, like the 6 km asteroid that caused the Tunguska Explosion every 5 million to 10 million years. Asteroids with a diameter of 10 km are held every 50 million to 100 million years.
The asteroid discovered this time is only 43 meters in diameter, and it is reasonable to say that the probability of collision with the earth should be very large, is the asteroid really going to hit the earth?
Effects of asteroids hitting The Earth
If you look at the volume and the probability of hitting the Earth alone, the probability of hitting the Earth is still very large, but the asteroid does not have a large enough threat. Astronomers stipulate that asteroids up to 150 meters in diameter are classified as "potentially threatening asteroids," and we all know that any asteroid about 10 meters in diameter will burn as it passes through the atmosphere, causing a thermal explosion to be destroyed. So what happens if the 43-meter-diameter asteroid actually hits Earth?
As early as 2013, Russia was hit by a smaller planet that was 15 meters in diameter and landed right in Chelyabinsk, Russia, causing millions of dollars in property damage and more than a thousand injuries.
In 2019, a large asteroid of "2019 OK" was discovered the day before it flew between Earth and the Moon and was the size of a football field, less than 65,000 kilometers from the Earth's surface. If the asteroid hits Earth, the shock wave will cause a 50-mile (about 80 km) wide area to be destroyed.
Nowadays, in the face of the 2022 AA, which is half the size of a football field, although it will fly by the earth at 341,000 kilometers recently, countries are also paying close attention to the movement of asteroids, if there is really any accident, we can also find it at the first time, deal with it, and prevent some accidents. Planetary defense is the right of everyone, it is related to the safety of everyone's life, and mutual cooperation between countries will help to better protect the common home of all mankind.