How big does a meteorite have to be to destroy the humanity?
Perhaps, among all the reasons for the "end of the world", the fall of a giant meteorite on Earth is always in the top three ideas. But how big does a meteorite have to be to leave humanity no chance of survival?
When it comes to a meteorite falling on Earth, there is one unshakable rule - the larger the meteorite, the more destructive and dangerous the consequences of its collision with our planet will be. Archaeological excavations and space observations over the past half century show that collisions of large celestial bodies with meteorites are not at all uncommon. On Earth, you can find dozens of tracks and impact craters from meteorites that fell here millions years ago.
If fairly large meteorites have already fallen on Earth and, as we know, were the culprit behind the mass extinctions of living beings, then a similar situation will surely repeat itself in the future. Back in 1997, researchers from the University of Colorado decided to find out what size a meteorite would be fatal for all of humanity, completely ending our civilization.
Calculations have shown that a cosmic body of 800 meters in diameter will generate an explosion with a yield of 100 megatons in TNT equivalent upon collision with the surface, which is comparable to the simultaneous explosion of two of the most powerful thermonuclear bombs in history. Such an event can cause earthquakes and tsunamis, the shock wave will travel around the globe several times, and fires will break out in some regions caused by light radiation during the explosion. However, it is unlikely that the fall of an almost kilometer-long meteorite will cause significant damage to the Earth.
Scientists are inclined that the meteorite that caused the mass extinction of the dinosaurs reached a diameter of 11-13 kilometers. If such a celestial body collided with the Earth today, millions of people would die instantly, thousands of kilometers of land would be engulfed in fire, and a huge amount of dust would rise into the air, which would reduce the brightness of sunlight for a long time, which would adversely affect plants. Under such circumstances, as we remember, dinosaurs could not exist and became extinct. But humans are not dinosaurs. Our progress has gone far enough for a part of humanity to be able to survive in such extreme conditions.
What diameter of a meteorite is needed so that a powerful shock wave does not leave humanity a single chance for survival? Experts have come to the conclusion that the "end of the world" will certainly come if the Earth collides with a celestial body with a diameter of 100 kilometers. And it is not so much by cosmic standards.
For the coming decades, the probability that terrestrial observatories could miss a celestial body with a diameter of 100 kilometers is small. However, if we are talking about the distant future, we need to talk not about whether there is a chance that a large enough meteorite will fall on Earth to threaten the existence of mankind, but about whether we will be ready to meet with it when this happens.
